Caring For The Vietnamese Centipede – January 2014

By Anthony Neubauer

The Vietnamese Centipede is a large invertebrate found throughout the jungles and tropics of Asia, especially southeast Asia where they are mostly imported from. There are also populations in Hawaii, and likely in other tropical climates throughout the world. Reaching lengths up to 12”,they are an active creature, scurrying through the jungle floor’s leaf litter as they search for their next meal. In captivity, they often burrow, but with a thought out setup,  they can be seen cruising around through vegetation and rearranging their enclosure. The Vietnamese Centipede is a great animal for the careful hobbyist.

Please Note: Centipedes in general are not for the inexperienced.  Not only do they possess powerful paralyzing venom, they are extremely prone to biting, and are one of the fastest, most unpredictable bugs you can deal with. I strongly recommend a long pair of hemostats, as they easily climb up tongs with astonishing speed. Although you can find pictures of it on the internet, handling should in no way be attempted. Centipedes tend to “test bite” everything they walk on, so an envenomation is almost inevitable. Please be responsible.

You don’t want to be on the receiving end of a bite from those chompers!

Selecting an Enclosure

Centipedes are escape artists, so if not housed in a 100% secure enclosure, they will get out at some point. I will only house them in glass tanks that have a sliding top lid with a pin to prevent it from opening. I prefer the sides to be taller than the centipede is long to create some space between my hand. It should also be tall enough to allow a few inches of substrate for burrowing, as well as a drainage layer if you plan to create a living vivarium, which is the best way to go. Anything from 5-10 gallons is enough space for even the largest specimen. I have heard of people keeping them in plastic enclosures such as those sold as “Kritter Keeper”, however, I would not trust all of the holes and gaps. The rule is: If the centipede can squeeze it’s head through, it can get it’s entire body through. Trust me from experience, you do not want one of these exploring the room you sleep in!

Water and Humidity

Perhaps the number one reason centipedes do not survive in captivity is hydration. Even so called “desert” centipedes do not live completely dry. In fact, when it is dry, they are no where to be found on the surface because they burrow down to the more humid layers of dirt. Vietnamese Centipedes come from dense, humid jungles, so they need to be kept as such. There are three steps to properly hydrating them. The first is always offering a water bowl full of water. Second, use a substrate that holds moisture well and will not mold. Third is regularly spraying down the enclosure. This is where a vivarium becomes most practical as you are watering the plants regularly anyway. Follow these three steps, and your centipede will thrive.

Temperature

Scolopendra subspinipes can be kept anywhere from room temp of 73*F, all the way up to 80*F. Keep in mind that at the higher end, they will act more natural, and be much quicker and aggressive. Many keepers will remove the heat source ahead of time if going into the enclosure is needed as this lets them cool down a bit and they tend to move a little slower. Still, do not let your guard down. Humidity is also harder to maintain at 80*F, so that should be accounted for.

Feeding

Feeding is an easy thing with these guys, as they are not picky. Any live vertebrate or invertebrate will be accepted. Crickets, Cockroaches, and mealworms and superworms are commonly available food items, and are the healthiest for the animal. Pinkies and feeder lizards can be offered occasionally, but they are not designed to digest vertebrates as much, so they tend to make them obese and have a  shorter life span. Large Cockroaches are what makes up a majority of their diet in the wild, so are probably the most beneficial and nutritious. Keep in mind that they are messy eaters, tearing their food up and often leaving a pile of bits and pieces of their meal. This should be removed as soon as possible due to the rapid growth of mold that is sure to happen due to the high humidity they are kept in.

Inside the Tank

When setting up a centipede enclosure, a few things should be taken into consideration. First, a thick layer of substrate should be provided to allow burrowing. Burrowing leads to a sense of security, which in turn leads to a comfortable centipede that will not be afraid to explore it’s enclosure. The enclosure should be made dense with either live or fake plants. Pothos plants make great live terrarium plants, as they have low light requirements, love a humid environment, and will vine out and climb all surfaces of the tank if allowed. They will also produce heavy ground cover if nothing is provided for them to climb up. This is perfect for your centipede. Live sheet moss is another great way to add humidity as well as a special aesthetic appeal to the tank. Stacks of broken cork bark also allows multiple hiding places, while looking good at the sametime. Cork bark will not mold, so is perfect for the centipede’s environment. For substrate, I recommend Cypress, Eco Earth, or my personal favorite, Tree Fern made by Exo Terra. The latter two will hold up better in a naturalistic vivarium a lot better, but if going for a simple and clean enclosure, Cypress will produced great results if changed once a month.

A Note on Venom:

Although there are no reliable reports of death by Scolopendra subspinipes, bite victims describe the experience as the most pain they have ever felt, with reactions ranging from severe pain with swelling, to slight necrosis of the tissue, accompanied with nausea, and unbearable pain. If bitten, a hospital trip should be arranged immediately to be on the safer side. Different subspecies have different levels of venom, but all should be treated with the same care and respect that a potentially dangerous animal demands. Think twice before purchasing a centipede if you share the house with children. Bottom line: Be responsible!

Differences among subspecies:

Scolopendra subspinipes subspinipes is the most commonly seen subspecies in the US. They are large, with 8-9” being average, and up to a foot not being unheard of. Colors range from the standard yellow leg, to cherry leg and tiger leg populations. Scolopendra subspinipes “de haani”is an extremely colorful subspecies, with varying degrees of deep red legs and body. S. subspinipes mutilans is a smaller subspecies,attaining sizes of around 5-6”. Their headplate, as well as their last body segment and terminal legs are a vivid red, with a black body and yellow legs. They are among the smallest of the species, and interestingly enough, are communal. I successfully kept 3 adults together for over a year. This is the only subspecies that is recommended to be housed together.

The Vietnamese centipede is a truly impressive invertebrate. When setup correctly, they can be a unique display animal that is sure to captivate its observers. As long as they are given their space, and measures are taken to prevent an escape, they make a very cool pet. Keep them hydrated and humid, and you’re sure to have your centipede for a very long time. The centipede is gaining popularity as more and more people realize the interesting behaviors and colors that come along with these prehistoric bugs.

Care for Mexican Fire Leg Tarantulas – September 2013

By Anthony Neubauer

Introduction

The group of tarantulas that make up the genus Brachypelma are ideal spiders for any hobbyist. Their generally calm demeanor, decent yet manageable size(5-6 inches), and stunning colors make them perfect for a display animal. Some tolerate handling more than others, but as with any spider, care should be taken when handling. My personal favorite, the Mexican Fire leg, is better kept for display. They are one of the most colorful members of the genus, and tend to stay out in the open for viewing.

When selecting a first tarantula, most people are instructed to start with “New World” species, that is, species that come from North or South America. New World species possess specialized hairs on the abdomen, called uriticating hairs, that are rubbed off as the first defense. These hairs, once airborne, cause itchiness and irritation. Some people are more sensitive to them than others, but they generally are of little worry. Because they possess these hairs, they are less inclined to bite, and possess less potent venom if they do. They also tend to be calmer and slower moving. This makes them more manageable for the beginner and intermediate hobbyist. The Brachypelma genus hails from Mexico and Central America, so fall into the New World category.

Selecting an Enclosure

When selecting an enclosure for a Fire Leg, one must keep in mind that they are a terrestrial species, so will spend their time on the ground. This is important, as housing them in too tall of cage can result in a fatal fall. Spiderlings are available as small as half an inch, and up until around two inches should be housed in a small, simple setup as locating their food and water will be tough in larger enclosures. I recommend an eight ounce deli cup up until two inches such asthis. Once they start gaining size, appropriately sized glass tanks or plastic enclosure can be used. For an adult Fire Leg, something with similar floor space to a 10 gallon tank is sufficient. Exo Terra Breeder Boxes and Flat Den Homes are an excellent way to save space, allowing for you to have more spiders!

Cage Décor and Substrate

For any tarantula to thrive, a hiding spot should be provided to allow the spider to feel secure and keep stress levels down. Hides can be anything from a coconut hide, to a piece of cork bark, to a stone cave or skull. Basically anything they can get under or in, and be mostly unseen. Commonly used substrates include Coconut Husk, Orchid Bark, and Cypress Mulch. A water bowl should also be offered for spiders around three inches and up. It should be shallow enough that there is no risk of drowning, and should be changed every couple of days to keep it clean. Spiderlings up until three inches should be sprayed once a week, and not given a water bowl, as this can cause drowning. They will drink the water droplets when they are sprayed. It is not recommended to use a sponge as a water source, as these quickly promote bacterial growth. Some keepers, particularly those interested in keeping Fire Legs for a display animal, choose to take the habitat to the next level and create a natural living vivarium, complete with live plants. This can be easily done with a little extra thought and consideration.  Keep in mind your tarantula’s needs when molting (higher humidity in particular), and you can recreate a desert- style vivarium with moist hiding areas.

Temperature and Humidity

Fire Legs come from the deserts and sub deserts of Mexico. However, no tarantula should be kept constantly dry or too hot. They can be kept at room temperature in most households, provided it stays around 70-73*. Ideally you’d be shooting for 78-80 Degrees, in which case they will metabolize and grow quicker. If you need to pump the temperatures up a little bit, you can use a Clamp Lamppointed at one side of the cage to raise the ambient temperature.

Heat pads can also be used, but should only be mounted to the side of a glass enclosure, as tarantulas burrow to escape heat, so an undertank heater would result in a cooked spider.

As adults, their substrate can be kept bone dry as long as a water bowl is provided. They should also be given higher humidity before they molt. This is achieved by lightly spraying the enclosure, and by adding wet Sphagnum Moss.

Feeding

Tarantulas in general have a low metabolism. They aren’t running around the cage all day, or doing much of anything, to be honest. As a result, they don’t eat a whole lot. Most spiders will eat one appropriately sized insect a week. Spiderlings can be offered Flightless fruit flies if they are too small to tackle live crickets. They can also be given a freshly killed small cricket, as they can be scavengers for their few months of life. It is not uncommon for your tarantula to skip a meal, or even go for a prolonged period of fasting. As long as they maintain a plump abdomen, they are perfectly fine. The most frequent reason that a spider refuses a meal is that is going through premolt, that is, it is preparing to shed its skin. Signs of premolt would be the tarantula kicking all of its uriticating hairs off, leaving a light colored bald spot that eventually turns black. After the process is complete, you will find a shed skin that looks just like your spider! They will also begin to regenerate legs during this time if any are lost.  Leg regeneration can take several molts and can be a complicated process for your tarantula, so while they can regrow their legs, it’s best that they not lose them in the first place.

Sexing

Sexing tarantulas is usually difficult until they mature. Once mature, males will possess “hooks” on their pedipalps, which are used for breeding. Once males “hook out”, they will only live for another year or two. Females will not get these hooks, and will instead live for around 20 years after maturing. This obviously makes females more desirable to acquire, however it is near impossible to tell until they are mature.  You can also sex tarantulas by examining their molts closely, but as this can be difficult without the right tools to see the right parts in a tiny spiderling molt, to be truly accurate it is best left to the dedicated tarantula enthusiast.

Conclusion

Overall, the Mexican Fire Leg Tarantula makes a perfect pet for beginning and advanced hobbyists alike. They are very hardy and easy to care for, but attain decent size and amazing color. They are not very quick, nor are they very bitey, but they do kick hairs and become nervous when disturbed, so they are better left as a “look-but-don’t-touch” pet. They can be kept in a simplistic setup, or in an elaborate vivarium. Either way, they will thrive as long as a  few basic needs are met. If you are looking for a colorful tarantula that is easy to deal with and maintain, stop looking and purchase a Mexican Fire Leg Tarantula!

 

Scorpion Fluorescence – August 2013

By Kevin Scott

Man’s highly developed color sense is a biological luxury- inestimably precious to him as an intellectual and spiritual being…. -Aldous Huxley inThe Doors of Perception

Aldous Huxley concisely described man’s fascination with things that shimmer and glow. The earliest admiration of the luminous was probably lightning at night, wildfires, the sun or a full moon.

To be sure, these things were revered and their causes unknown to the point that gods and goddesses were invoked, whose attributes described these phenomena.

Fast forward several millennia to the advent of artificial ultraviolet light and another curious phenomenon is observed: the fluorescence of scorpions under a black light. After the initial curiosity one comes to wonder what the purpose of this could be and how works.

Wild california scorpion while illumated with a blacklight

Light in the ultraviolet wavelengths is certainly not abundant at night (although the proportion of ultraviolet to white light is higher at night), so why the glow? The wavelengths in question abound during the day, but scorpions are decisively nocturnal animals that have well developed sensory mechanisms, allowing them to efficiently hunt and mate in low levels of light. The chart below describes some of these adaptations (Blass and Gaffin 2008).

Although all of these adaptations allow scorpions to capture prey, navigate and reproduce in low-light conditions, they do have several photosensory organs as well.

Emperor Scorpion, showing both fluorescing color and normal color

Scorpions have lateral and median eyes that are capable of detecting light magnitude changes and image formations, respectively (Gaffin, et al. 2011).   The median eyes are most sensitive to wavelengths around 500 nm (green) and secondarily sensitive to light in the 350-400 nm (ultraviolet) range (Machan 1968, Fleissner & Fleissner 2011).

In addition, scorpions have a metasomal element that is sensitive to light in the green area of the visible spectrum (Zwicky 1968, 1970; Rao & Rao 1973).

These technical details may at first seem superfluous until one thinks about the fact that when one views a scorpion under a black light, the black light and the green glow are in the same areas of the light spectrum as those to which the scorpion’s eyes are most sensitive; this is probably not a coincidence.

But this still does not explain the function of the fluorescence. Although the exact purpose is not known, there are a few hypotheses. There is the obvious possibility that no function is served at all.

Gary Polis suggested that fluorescence could act as a lure to draw prey in, but subsequent tests of this hypothesis show that insects will actually avoid scorpions that are fluorescing (Polis 1979; Kloock 2005).

One other theory suggests that fluorescence may play a role in courtship behavior, allowing one scorpion to tell whether a near by scorpion is of the same species and/or of the opposite sex (Kloock 2008). This would allow, from a distance, a scorpion to decide to approach (or be approached by) another that is either of the same sex or of a different species – either would be futile in a mating attempt. A negative photoresponse is observed in scorpions suggesting that the cuticle may serve as a photodetection device, however, it is not clear that fluorescence plays any role in this. One study showed that prolonged exposure to ultraviolet light caused a decrease in fluorescence (Kloock 2009).

Although the exact function has yet to be elucidated, mechanism by which fluorescence occurs in scorpions is relatively well understood. The scorpion’s exoskeleton is made from chitin, like other invertebrates. The compounds that fluoresce are found near the surface of the cuticle and relatively recently two molecules (4-methyl-7-hydroxycoumarin and beta carboline) have been isolated, both of which fluoresce in the presence of ultraviolet light (Stachel et al. 1999; Frost et al. 2001). Interestingly, Polis points out in his book The Biology of Scorpions that scorpions that have newly undergone ecdysis do not exhibit total fluorescence until 48 hours thereafter.

Fluorescence is observed in many life forms. Some of their functions are understood and some remain a mystery. Significant progress has been made with respect to that of scorpions, but more work is needed to fully understand the function thereof. For anyone who is interested in a deeper understanding of any of the topics discussed here, please explore some of the books and papers referenced below.

Blass, G. R. C & Gaffin, D. D. 2008. Light wavelength biases of scorpions. Animal Behaviour, 76, 365-73.

Gaffin, D. D., Bumm, L. A., Taylor, M. S., Popokina, N. V., & Mann, S. 2011. Scorpion fluorescence and reaction to light. Animal Behaviour, 83, 429-36.

Fleissner, G. & Fleissner, G. 2001. Night vision in desert scorpions. In: Scorpions 2001; In Memoriam Gary A Polis (Ed. by V. Fet & P. A. Selden), pp. 317-324. Burnham Beeches, Bucks: British Arachnological Society.

Frost, L. M., Butler, D. R., O’Dell, B. & Fet, V. 2001. A coumarin as a fluorescent compound in scorpion cuticle. In: Scorpions 2001; In Memoriam Gary A Polis (Ed. by V. Fet & P. A. Selden), pp. 363-368. Burnham Beeches, Bucks: British

Arachnological Society.

Kloock, C. T. 2005. Aerial insects avoid fluorescing scorpions. Euscorpius, 21, 1-7.

Kloock, C. T. 2009. Reducing scorpion fluorescence via prolonged exposure to ultraviolet light. Journal of Arachnology, 37, 368-370.

Machan, L. 1968. Spectral sensitivity of scorpion eyes and the possible role of shielding pigment effect. Journal of Experimental Biology, 49, 95-105.

Polis, G. A. 1979. Prey and feeding phenology of the desert sand scorpion Paruroctonus mesaensis (Scorpionida: Vaejovidae). Journal of Zoology, 188, 333-346.

Rao, G. & Rao, K. P. 1973. A metasomatic neuronal photoreceptor in the scorpion. Journal of Experimental Biology, 58, 189-196.

Stachel, S. J., Stockwell, S. A. & Van Vranken, D. L. 1999. The fluorescence of scorpions and cataractogenesis. Chemical Biology, 6, 531-539

Zwicky, K. T. 1968. A light response in the tail of Urodacus, a scorpion. Life Sciences, 7, 257-262.

Blaptica dubia: Equal Opportunity Feeder – July 2013

By Jonathan Rheins

Meet the Roach

As a whole, herpetoculturists are a resourceful bunch. For decades and decades we have studied, maintained, and bred a large number of diverse species in an artificial environment.  Over the years, fore-thinking herpers of all backgrounds have scratched their collective head and struggled with all of the “what-ifs” and “maybes” of our hobby.
In addition to creative solutions regarding lighting, heating, and housing needs, we have also made great strides in the realm of nutrition. Perhaps the most important being those of the constantly evolving list of tried and tested live feeder options.
Be they crickets, mealworms, mice, or rats, there are a growing number of feeders that have become mainstream staples for those wishing to keep reptiles and amphibians as pets.
However, other options exist for even the pickiest insectivore palate. Roaches.  Yes, the scurrying, invincible, invertebrate denizens of our nightmares can actually provide an incredibly healthy and balanced diet for cold-blooded creatures of all shapes and sizes.

 It should come as no surprise to many readers, but not all roach species are our friends.  Pest species can certainly wreck havoc on the pantry and nerves of even the most liberal naturalist.  That said, even the venerable commercial cricket can just as easily outwit our human coordination and “make a run for it.”

Fortunately for us, most of the commercially available roach species are of tropical origin and simply cannot thrive in the relatively cool and dry conditions of many regions of the United States.  In the case of accidental escape, these roaches will most likely die off rather than initiate a plague of any sort.
The commercial breeding of roaches for herpeteculture use is quite new to many American keepers.  However, these misunderstood arthropods have long been commonplace feeders in European collections and in those of zoological institutions and professional breeders throughout the world.
The consensus among many reptile keepers and breeders who are in the know is that of all the roaches out there, Blaptica dubia are as close to perfect as a roach species can be.  They are easy to deal with, nutritionally sound, and absolutely irresistible to every herp they meet.

Dubia Details

Blaptica dubia is a medium sized, South American roach species belonging to the family Blaberidae.  All genera within this family are ovoviviparous.  In cases of ovoviviparity, fertilized eggsacs known as oothicas are carried internally by the female roach until the eggs are fully developed.  Hatching takes place within the abdomen of the female, and at that time baby roaches (nymphs) emerge as fully developed miniature versions of the adults.
Within the United States, common names for B. dubia include Orange-spotted roach, Guyana-spotted roach, and most commonly, theDubia roach.  Latinized scientific names are always the most reliable system for describing any animal species. Furthermore, the use of Latin names ensures that the roaches being purchased, bred, or sold are identified in a consistent and accurate manner.
Dubia roaches are approximately 1/8 inch long at birth and measure just shy of 2 inches in length at maturity.  Adult dubia are sexually dimorphic, with males and females being easy to pick apart at a glance.  Males posses large wings that extend the length of the abdomen, while females have only small wing stubs, barely covering the “shoulder” region.
Flight among dubia roaches is very rare.  Despite being capable of hovering for short periods, this is a behavior that most keepers will never witness nor need to be overly concerned about.  Furthermore, B. dubia are poor climbers, and are nearly incapable of climbing smooth surfaces such as glass, acrylic, and plastic.
Breeding roaches for use as feeders is not a difficult endeavor, and maintaining multiple colonies is a worthwhile consideration if many herps are being maintained, or if feeder availability is locally seasonal or absent.  The details of breeding dubia roaches are beyond the scope of this article, but can be easily researched and implemented by the interested hobbyist.

Roach Motels

As with any live feeder, having a secure container to house them in until needed is highly recommended for keeping dubia roaches.  The use of a holding container allows for more roaches to be purchased at once, saving on feeder runs and shipping.  Furthermore, small roaches or nymphs can be purchased and raised up until they are the perfect size for being fed off.
While not strictly necessary, the use of a tight-fitting and well-ventilated lid is highly recommended.  There are many acceptable containers for temporarily housing dubia roaches including small glass terrariumsplastic faunarium critter keepers, and deli cups.

Substrates are not needed in dubia habitats, and using them may actually make cleaning and collection of tiny roaches more difficult. Dubia roaches have very little odor, and if attention is paid to cleanliness, ventilation, and removal of uneaten foods, there should be minimal smell associated with the roach container.
Hiding and climbing structures should be added such as cardboard toilet paper tubes, egg crates, or even vertically stacked cardboard pieces.   These will provide increased standing room for larger groups of roaches by allowing them to spread out and not smother each other.  Roaches that feel hidden and secure will thrive and grow faster than those under constant stress.
B. dubia is capable of surviving at temperatures between 70 and 95 degrees Fahrenheit, making them quite tough and adaptable.  Roaches kept at room temperature will survive and fare well, but as temperatures increase, more rapid growth will become evident.
The dubia holding container should be kept in a warm room in the home, or heated artificially if this can be done safely.  If external heat sources such as heat pads or heat cable are used, a high quality thermometer and appropriate temperature control device are recommended.
Blaptica Buffet

Feeder insects are only as healthy and wholesome as the foods they eat themselves.  Offering hungry, malnourished feeders to herps is akin to a human eating a hamburger that is nothing but an empty bun!  What’s on the inside is quite important in ensuring that a meal (roach, hamburger, or otherwise) is nutritionally well rounded.
The process of providing water and nutritious foods to future prey items is known as gutloading.  Feeders that have been gutloaded are many times more nutritious than “empty” feeders, and careful planning can allow for specific nutrients to be added or removed from the diet as needed.

There is more to gutloading roaches than just keeping them alive.

Just as with any other living creatures, they should never be deprived of food and water for any period of time.

B. dubia are opportunistic scavengers and in the wild they feed constantly on nearly any plant or animal matter they come across.

Fortunately, replicating such a diet for our feeder roaches is exceptionally simple.

After all, roaches are one of nature’s most devoted recyclers, and not very picky about their menu.  A staple diet of commercial insect gutloads such as Repashy Bug BurgerNature Zone Total Bites, or Fluker’s Orange Cubes work very well.  Supplement the diet with fresh fruits and vegetables as well as unsweetened cereals and grains.

Being the poor climbers that they are, food for dubia roaches should not be offered in feed dishes that are more than a few centimeters in height.  Rather, use a piece of paper, deli lid, or shallow dish to offer food.  Avoid placing food directly on the floor of the container in the interest of cleanliness and mold prevention.
Moisture should be provided at all times in the form of fresh produce and the use of a water replacement crystal/gel such as Nature Zone Water Bites.  These gels provide water and increase container humidity without the risk of roach drowning.
Feeding Time

Handling dubia roaches and offering them as feeders is not as complicated as one may expect.   While dubia roaches can run, they cannot jump or fly, and like mealworms, they cannot escape from smooth-sided feeding dishes.
Appropriately sized roaches can be easily shaken off of their egg crate and directly into a wide mouthed jar or even through a funnel. Appropriate powdered supplements can be added as per the traditional “shake-and-bake” method.
Feeding dishes with smooth, steep sides work very well for offering dubia roaches to mostreptile species.   Worm dishes designed specifically for use with live mealworms can also work quite well depending on the size and quantity of roaches being presented.  Some creativity and experimentation may be needed to get it just right for any given situation.
In glass enclosures, rack systems, or other roach proof reptile terrariums, dubia roaches may be dumped directly into the enclosure and allowed to picked off over time by the hungry resident.  Many reptiles, amphibians, invertebrates, and even fish will learn to eagerly snatch dubia roaches straight from the end of a pair of tongs!
Roaches may be slowed down before offering to herps that are less enthusiastic about hunting.  This can be accomplished by placing the roaches in the freezer 1 for-minute increments until the desired level of sluggishness has been achieved.  Responsibility and good judgment are musts for anyone wishing to chill their roaches.
Dubia roaches are less likely to cause unexpected harm to terrarium residents than some other feeder insects.  This is not to say that dozens of excess roaches will not cause stress or possible injury to an innocent leopard gecko.  It is however worth mentioning that a few uneaten roaches are not likely to bother most reptile pets.  Care should be taken however to avoid creating roach breeding conditions within a large, complicated terrarium.
Hit or Miss

There are many advantages to incorporating dubia roaches into the diet of captive reptiles and amphibians.  Dubia are a hardy roach species, they are unable to climb smooth surfaces, are nearly odorless, and are highly nutritious.  Furthermore, they are nearly irresistible to herps of all types.
However, despite this laundry list of qualifications, dubia are still a species of cockroach, and thus carry the heavy burden of a biased public.  After all, roaches can become household pests in many parts of the world.   It is understandable then for newcomers to question bringing roaches of any type into their homes.
Overall, and with basic attention to detail, dubia roaches really do make excellent feeders.  They are readily available, reasonably priced, and perhaps best of all, no one will be kept awake all night by their insistent chirps!
Dubia roaches pose little threat of escape or domestic infestation.  They are just as easy to handle and manage as any other invertebrate feeder, and properly kept dubia roaches will have no objectionable odor.
In Closing
Dubia roaches are rapidly encroaching on the fringe of what dictates a “normal feeder.”  While they are new to the scene, and unfamiliar to many, they hold a tremendous amount of promise as an easy, readily available food source for animals of all sorts.
Herps love them, as do tarantulas, scorpions, and fish.  Even picky eaters will jump upon the opportunity to have their dubia fill.  Feeder roaches may not be for every keeper or every herp.  But given the proper circumstances, dubia roaches could easily prove to be among the most perfect feeders.

Keeping Androctonus sp. in Captivity – July 2013

By Anthony Neubauer

Androctonus is the genus that contains the commonly called Fat Tail Scorpions. As the name suggests, these scorpions have an enlarged tail that allows them to possess more of their already toxic venom. They are recognized as some of the world’s most dangerous scorpions, and this should be kept in mind when choosing housing and while performing cage maintenance. The two most commonly available species in the U.S. hobby are the Yellow Fat Tail, Androctonus australis, and the Black Fat Tail, Androctonus bicolor. The care for each one is nearly identical as they are both naturally found throughout Africa and the Middle East.

Scorpions naturally have a slow metabolism, as they spend much of their time in burrows and under rocks. Because of this, they don’t require too large of an enclosure. However, they love to burrow and rearrange their cage, so one that allows burrowing is preferred. A cage size similar to a 5-10 gallon tank will be plenty large enough. The 12x12x12 glass reptile tanks offered by Exo Terra and Zoo Med make perfect and secure environments for these scorpions, as a lock can be purchased for added security. Since they are a desert dwelling species, a substrate that is dry and does not retain humidity is a must. I personally use a half-and-half mix of Zoo Med ReptiSand and Excavator clay. This allows your scorpions to dig and burrow as they would in the wild. Sand can also be used by itself, though you will want to offer more places to hide, such as flat rocks and wood. As for temperature, 75-80 degrees Fahrenheit is ideal. This can be achieved by placing a low wattage heat lamp on top, or a heat pad stuck to the side.  No special lighting is required as scorpions are nocturnal. They should be offered one or two appropriately sized crickets or roaches per week. A small water bowl can be offered, or the cage can be sprayed very lightly once or twice a month. They don’t require a lot of water because they get most of it from their food.

All in all, they are an easy-to-keep pet that doesn’t require daily care. If provided with a red nightlight, they can be seen throughout the night digging and rearranging their decor. However, they are a highly venomous animal that should be treated with respect. Their toxicity matched with their defensive personalities makes them a species that should only be kept by the more advanced and responsible hobbyist. Long tongs or hemostats should be purchased for performing maintenance, and under no circumstance should they be handled. If you’ve owned a lot of other scorpions and are ready to take it to the next level, then the Androctonus genus may be a good addition to your collection.

The Chaco Golden Knee Tarantula – March 2013

By Shawn Bowman

Grammostola Pulchripes

Have you ever been curious about owning a tarantula for yourself? The Chaco Golden Knee Tarantula is an excellent choice for a first time arachnid due to its mild temper, low maintenance, and large size!

There is no doubt about it; tarantulas are one of the lowest maintenance pets you can have!

Gold knee tarantulas are a burrowing species so deep bedding is suggested.

A five gallon enclosure with 3 to 4 inches of bedding will be used if provided.

Any of the coconut beddings such as Eco Earth or Plantation soil will work well. Some keepers choose to mix in bark or vermiculite.

Keep the bedding fairly dry with a weekly misting. A small water bowl can be provided however most spiders are okay with occasional misting and food items as their water source.

The spiders should be fed an appropriate sized prey item once or twice a week. Depending on the size of the tarantula, this can range from a fruit fly to large crickets. It is important not to feed more crickets than the tarantula will be eating.  If crickets die in the tank the natural mites a cricket carries will multiply, and the large number of mites can eat your tarantula while molting. That being said, one large, easy to catch prey item is usually better than multiple small prey items.

Why a Chaco over another species of tarantula?  The size is what’s cool about these arachnids.  They are generally as docile as their relative, the Rose Hair Tarantula. It gets a leg span that reaches up to 8 inches making them one of the more impressive large tarantulas that could be considered a beginner species. The female spider can live as many as 20 years with male spiders averaging a lifespan of about 3 years.

When looking to handle your tarantula, keep in mind each animal is going to act a little different. I suggest getting your tarantula at a small size because this species is usually not aggressive as a spiderling and is typically very easily handled. This will help build your confidence and understanding of the tarantula before it attains its full size. Keep in mind that they can bite if they feel threatened.  Slowing  down and reading the signs of your spider is the best way to keep yourself out of danger and keep your tarantula happy!

10 Questions with Phil Goss of USARK – March 2013

by Scott Wesley

10 Questions with Phil Goss – New President of USARK

Phil has taken on the difficult task as the new president of USARK (United States Association of Reptile Keepers). He has been in and around the hobby for years and has a passion forreptiles as we will find out in this interview!

1. Let’s start with an easy and obvious question. What first got you into reptiles, and what was your first pet reptile?

Thank you, Reptile Times and LLLReptile, for the opportunity to answer some questions. I have always been intrigued by all animals, especially herps. I grew up in a very rural area filled with herps. Nature surrounded me and I was more than happy to enjoy it. I constantly found American toads, Northern cricket frogs, painted turtles, musk turtles, banded water snakes and other herps found in southern Indiana. I would investigate them and let them be on their way. These field herping experiences sparked much reading and research concerning reptiles and amphibians. My first purchased snakes were a normal corn snake and a black and white banded kingsnake.

2. What was your first job in the reptile industry, and how did you make that transition into your job at Zoo Med?

My first pet industry job was working at a retail pet shop in Bloomington, IN. The owner of the shop provided me with an amazing amount of knowledge concerning the industry and she was a very positive influence. After graduating college, I stumbled upon a job as a sales representative for a small dry goods distributor. We sold all pet-related products except dog/cat foods and carried all major reptile brands. I spent the first few weeks in the warehouse pulling orders and learning about the products. Even though I was out of school, I still had plenty of homework. This greatly helped when I hit the road as a sales rep and visited pet shops in Indiana, Ohio and Kentucky.

In 2005, I heard Zoo Med had a sales position available. I delayed sending a resume as the Backer trade show was coming to Chicago soon and I knew I could personally introduce myself to Zoo Med there.

I certainly should not have delayed as the position was almost filled before Backer. A very important lesson was learned not to delay when opportunities arise but I was thrilled to have a job with Zoo Med.

3. A more serious question…  It seemed to me that a larger focus of USARK was on big snakes in the past.  Understandable, as they have made the headlines over the last few years. However, the reptile industry is so much more than just snakes. How are you planning to incorporate all herps into the conversation and unite breeders, stores and hobbyists alike so we can all get on the same page?

Breeders, stores, hobbyists and keepers need to unite and unite now. Recently, big constrictors were an easy target due to their perception by the general public. History is forgotten quickly and laws such as the 4” turtle ban from 1975 are not discussed often. Everyone in the reptileindustry should be proactive and act now rather than waiting for their species of choice to be attacked. Large boid and venomous keepers are not the only potential victims. Thinking, “I will not be affected because I breed leopard geckos.” is simply not acceptable. Wilson County, Texas just fought a ball python ban and proposed legislation using blanket terminology such as “reptiles” isbeing introduced. If little, cute, baby turtles can be banned, any herp can be banned.
As mentioned, large constrictors have been the focus of national legislation recently. USARK fought these battles as those were the rights being threatened. However, it has been USARK’s mission statement from the beginning that we protect the right to keep any reptile, amphibian and invertebrate.
It is crucial that everyone in the herp community follows legislation, owns reptiles responsibly and educates the general public concerning reptiles. If we lose our right to keep large snakes, we will continue to lose rights to keep smaller snakes. If we lose the right to keep large lizards, small lizards will come next. Large constrictors have been the focus due to being sensationalized by the media. They were an easy target but any reptile could be the next target.
Breeders, hobbyists, store owners and everyone in the reptile industry must join forces. Our community is too small to be divided and expect to win battles over much larger and well-funded anti-herp groups. Though we battle larger anti-pet groups, if united we are stronger and more devoted than anyone else and we will not back down.

4. At LLLReptile – we firmly believe that education is key (which is a big part of why we put out this magazine). Do you have any thoughts or suggestions as to how our industry can educate the “masses” versus just the reptile keepers themselves?

Education is certainly a key component. It is very easy to change the attitudes of people who have never interacted with reptiles but they must be presented with the opportunity to learn. People who are afraid of snakes due to lack of education or interactions with reptiles will not go seeking knowledge to learn about snakes. We must present our industry in a positive light and spread proper education.

It is much easier to spread knowledge today than many years ago. More people are attendingreptile shows and more educational reptile shows are popping up. When you attend a reptileshow, take your friends, even if they are not herpers. Everyone attending a reptile show may not buy a reptile but if he has a good experience and learns about reptiles then we have a future hobbyist.

The internet makes it easy to post educational videos and articles. There are education-oriented herp groups arising and I hope to see great happenings from these organizations. Herp societies are still educating and if you are not a member of a herp society, you should join one. If there is not one in your area, get some herper friends together and start one.

The key is to show positive aspects of reptiles and share constructive information. I am amazed at how many local television and radio stations are allowing herpers to speak. Do not sit around and wait for opportunities. Pick up the phone and send emails to local affiliates and offer to present a show concerning reptiles. Remember to be prepared and professional. Highlight responsible pet ownership, why reptiles are good pets and educate the audience. If we make enough ripples, a wave will follow.

5. I have heard you currently work with Prehensile Tailed Skinks (aka Monkey Tailed Skinks).  Have you had any luck breeding them, and do you have any husbandry suggestions for our readers?

Proper caging is a big concern. I utilize custom plastic cages measuring 4’Wx4’Hx2’D, though even larger is better. This could house a pair or even 1.2 or 1.3 skinks and should be filled with large cork rounds, suitable branches and plenty of hiding areas. However, be sure to watch closely for aggression as these skinks must be compatible to be housed together. My caging has a partial heavy gauge screen top, shelves, removable median divider and automatic misting system. A proper basking area and UVB should be provided. I have had success breeding monkey tails in this style cage. I do separate males and females for a few weeks before introduction. Again, be sure to watch for aggression. It is normal for the male to bite the female but if the female squares off for battle, separate them and introduce again a day or two later.

Prehensile-tailed skinks are very interesting reptiles. If you are prepared, they are great lizards to keep. I have seen many cage aggressive animals that are perfectly fine when removed from the cage. Gloves may be used by some keepers as they do have sharp toenails and strong legs but toenails can be trimmed. They are certainly one of the most interesting reptiles in the herp world.

6. Boas are also a passion of yours. Can you tell us some morphs you are working with, anything really different on the horizon, and why boas specifically got your attention?

Boas always fascinated me more than other snakes. Their colors, body shape and demeanor just amazed me from the beginning. I have several Boa constrictor longicauda and these are a very interesting Boa constrictor subspecies. I had some very aberrant babies in a 2011 litter and also have anerythristic babies occasionally. Longicauda are highly variable, even among wild-type animals. The strong head markings and bold body pattern contrast sets them apart from other boa constrictors. They are born looking very similarly to common boa constrictors, but their markings darken with every shed to make them easily distinguishable from others boas as adults. The various localities and subspecies appeal to me most, especially as many of these have nearly disappeared from the hobby. True red-tailed boas, Boa constrictor constrictor, are rarely seen today and are the snakes that first made me a boaphile (enthusiast or lover of boas).

Concerning Colombian morphs, I do not have any crazy, high-end animals. I keep a few morphs but my collection is heavier with various subspecies and Boa constrictor imperator localities. A female albino arabesque is the favorite morph in my menagerie.

7. Can you give us a short argument as to why the average hobbyist should be allowed to own such snakes as Reticulated Pythons and Green Anacondas?

Every person should have the right to own any reptile. If someone researches and prepares for a reticulated python, understanding lifespan, adult size, cage requirements, etc., then he should be able to own a reticulated python. This applies to all reptiles and not just the large species. Be prepared and willing to accept the responsibilities of any reptile you buy for his entire life.

Simply stated, every person should have the right to own a reticulated python or green anaconda but not every person should own one. America is about having rights, not losing them.

8. We got our start at LLLReptile breeding Leopard and African Fat Tailed Geckos. I have heard you started in a similar fashion breeding those along with some day geckos. Do you still work with any geckos today?  Ever produce any unique Leopard Gecko morphs back in the day?

Due to heavy travel schedule, I no longer keep any geckos. I do miss keeping them but know I cannot care for them properly. As far as unique, I did have a small group of leopard geckos that stayed small, had blocky heads and produced extremely orange babies with occasional melanistic spots. These “blockheads” were very hard for me to rehome as I was amazed everytime I looked at them and they had great personalities.

Someday I will again have a large vivarium with live plants and day geckos. I definitely miss keeping geckos but I know they will be available when I can again care for them properly as long as the entire herp community stands up, unites and supports our fight.

9. Working for a company like Zoo Med in sales has to have given you some quality experience interacting with people face-to-face. Do you think this experience will help you in conveying the herp industry’s message to people outside of our circle?

That sales job certainly provided much experience working with people and dealing with difficult situations. Dealing with so many people means different approaches are needed to suit different personalities and you must always be quick on your feet. The job as Central U.S. Sales Manager for Zoo Med was not a “used car salesman” role, which will greatly aid me. The job was about building relationships and keeping lines of communication open. Professionalism at all times is a must if you do not want to tarnish earned respect.

The herp industry is comprised of amazing people and they need to be seen in a better light. USARK will always act in the best interests of the entire herp community and will certainly not hinder our progress with those outside the industry. A suitable spokesperson will certainly advance our efforts in an efficient manner. When I was employed by Zoo Med, I knew my role was just a small part of a larger, successful company. I was representing Zoo Med but I alone did not make Zoo Med successful. That applies much more now. USARK and the herp community are much more than just me.

10. Why do you think USARK chose you to be the face of this industry?  Why did YOU accept this rather daunting task? And what are you looking forward to most in 2013?

Perhaps most importantly, this role requires someone who is approachable, professional and unabrasive. The herp community cannot be united by a dictator. Having a standoffish public figure will continue to alienate us and make it harder to be understood by the general public and to gain allies for our cause. Also, understanding that USARK is larger than any one person is critical. Level-headiness and ability to accept criticism are other characteristics needed. Rising above and not participating in petty drama is also key. Having backgrounds in education and sales prepared me for many aspects of this position, including those discussed above. You will see a much more appreciative USARK and anyone supporting the community will receive proper accolade.

Seeing a divided community was not acceptable to me and being uncertain of who would represent us gave me doubts concerning our future. It is very daunting, especially in the beginning, but the USARK Board is taking an active role. The USARK Board of Directors is comprised of experienced industry leaders with only the best interests of the entire community in mind. They have no hidden agendas to harm our hobby or benefit themselves as individuals.

For 2013, seeing a united herp community would be at the top of the list. USARK’s paramount legal team in Washington will support our legislative concerns but our community needs to be active and strong. The entire reptile world needs to realize that anyone may be affected by outside legislation. If anyone has concerns with USARK, please discuss them with me at shows and hopefully keep negative energy off the internet and forums.

Having attended reptile shows for well over 15 years, I recall actually talking about reptiles and building friendships at shows. I enjoy few things more than listening to respected industry leaders tell stories about “the good old days.” Herps are what bring us together and we need to remember this.

Final thought for 2013… I want to see what we can do as a whole and not just what I can do as an individual.

Thanks again, Reptile Times, for doing your part to educate and support the herp community!

Getting to Know Gryllidae – February 2013

By Jonathan Rheins

Getting to Know Gryllidae

The venerable cricket (Family Gryllidae) has become a mainstay fixture in the world of feeder fodder for all keepers of reptiles, amphibians, invertebrates, fish, and even small mammals.  Easily propagated, readily available, and of acceptable nutritional value, the cricket makes an ideal staple diet for many species, both in the wild and within the home vivarium.

While certain variables do exist, the nutritional value and rearing care for crickets is quite stable regardless of species.  There are a number of cricket species available to US hobbyists, and the list expands when an international scope is considered.

Within the United States, the type and availability of feeder crickets will vary based upon geographical region, season, legal variables, and outside influences such as the recent virus-related production issues of particular species in certain areas of the country.

A special note should dictate that viral issues associated with the propagation of certain cricket species are not indicative of an unhealthy feeder cricket.  These ailments are specific to the genus, and will most certainly not spread to any animals consuming said crickets.

Among the genera of cricket likely to be encountered in the North American trade are; AchetaGryllus, and Gryllodes.  Regardless of genus and/or species, the steps required to maintain small-to-moderately sized holdings of these species are nearly identical.

The goal of this article is to impart upon the hobbyist a thorough understating of basic cricket care, the steps and importance of preparing these animals to be offered as food, and a multitude of tips and tricks to ensure success every time.

The Physical Cricket

Whether you are purchasing a dozen crickets at a time, or a thousand, it is imperative that the keeper has a firm grasp on the size/age of the crickets being purchased.  Furthermore, all of the species discussed herein grow rapidly, and this rapid maturation should be taken into account if more than a few weeks-worth of feeders are purchased at a time.

At birth the cricket species within our discussion are just about the size of the period that follows this sentence. These are colloquially referred to as pinhead (aka newborn) crickets.

Within a few weeks of adequate care, most crickets will approach the ¼” mark, about the size that is recommended for baby bearded dragons, leopard geckos, and adult dart frogs. Once this size/age is reached, maintenance and handling becomes significantly easier and less precarious for the crickets themselves.

Factors such as diet, temperature, and species will affect the rate of cricket growth, but on average, crickets double in size every 2 weeks.   Therefore a 4-week old cricket can be expected to measure between ½” and ¾” in total length.  Mature crickets of 1” or more are typically seen at an age of 6 to 8 weeks.  Again, many factors will contribute to the growth rate of crickets regardless of species and genetics.

Standing Room Only

When attempting to maintain any quantity of feeder crickets, the first step is to locate an appropriately sized and secure holding container.  Between 40 and 100 ¼” crickets can be comfortably housed in a container such as a Mini Faunarium , which is slightly smaller in size than a standard brick.  As size and quantity of crickets increases, so should the size of the enclosure being utilized.  A holding tank the size of an Extra Large Critter Keeper or standard 10-gallon aquarium is adequate for 500-1000 appropriately sized crickets.

The key to successful maintenance of crickets in any quantity is space and standing room.  Despite being ectothermic (body temperature influenced by external environmental factors), crickets en masse tend to generate a considerable amount of external heat and while they do not “sweat” in the traditional sense, condensation can form, which is a leading cause of cricket mortality.

Crickets of most species likely to be encountered will grow and thrive at slightly above room temperature.  For rapid growth and reproduction, ambient temperatures approaching 85° Fahrenheit are acceptable.   For typical day-to-day holding however, 75° to 80° should be considered maximum.

It should be noted that temperatures approaching freezing can be tolerated for short periods by some species, although typical repeated lows should be remain at or above 60° Fahrenheit.   As mentioned earlier, all genera of Gryllidae rely on external sources to regulate body temperature. As such, they are a fairly hardy group of insects, however, in all cases, lower temperature extremes are much less likely to prove rapidly detrimental than excessive heat.

On Solid Ground

In addition to maintaining a stable temperature within the cricket habitat, an appropriate substrate will ensure proper waste absorption as well as keeping humidity and moisture levels with a reasonable range.  While some keepers opt for a substrate-free enclosure, many find that utilizing a high-quality, dust-free flooring aids greatly in managing odor and moisture levels.

Chipped aspen shavings are an excellent option for cricket substrata.  These products are nearly sterile, dust free, and compact nicely for easy removal of small crickets and food waste.  Shredded aspen is another alternative, as is the use of shredded or pulverized coconut husk beddings.  Depending on your specific needs, a substrate should be chosen that allows for the proper humidity and temperature levels to be consistently maintained.

In order to increase surface area for held feeder crickets to assimilate, the addition of egg cartons, paper towel rolls, or even bunched up paper should be provided.  This will ensure that multiple specimens will never need to occupy the same space within the enclosure.  This small bit of “breathing room” is a simple but necessary consideration when keeping crickets in any quantity.

Herps Are What They Eat

Whether a cricket destined for consumption is kept for a day or for a month, they must be provided with food and water, as per any other animal.  Not including these provisions for feeder crickets is not only harsh for the insects themselves, but vastly decreases the moisture and nutritional level of the cricket at the time of being consumed.

The term “gut-loading” has come to loosely define the process of providing feeders of any species with a healthy and nutritious diet.  This practice not only ensures the survival of the feeder animal itself, but also affects the gut contents and consequent nutritional value of the prey item ultimately being consumed.

Naturally, crickets are opportunistic scavengers.  They will consume organic matter of any type including plants, carrion, fungi, as well as the weaker members of their own kind.  Providing a diet for captive raised crickets is a simple matter.  They need both a constant source of moisture and food.

Among the most tried and true means for feeding a cricket colony is via the provision of a constantly available, yet separate food and water source.   A dry, grain-based diet such as Fluker’s Cricket Feed or the pelleted Cricket Food from Rep Cal will provide crickets of all sizes with a well-rounded diet.  The addition of a water replacement such as Nature Zone Water BitesFluker’s Cricket Quencher, or a similar gelatinous water crystal will serve as a source of moisture for the crickets.  Liquid water within the cricket habitat will quickly lead to excessive drowning losses and bacterial growth, and should be avoided.

For those cricket caretakers with less time on their hands, there are an assortment of “complete” food, water, and gut-load products available that cover all aspects of cricket and other invertebrate feeder care in one simple step.  These products come either ready to feed (Nature Zone Total BitesFluker’s Orange Cubes) or in an easily prepared powdered form such as Repashy’s Bug Burger and similar products.  The goal of these products is to provide both sound nutrition as well as water to feeder insects of all sorts.

In the End

It may seem like a handful of crickets tossed into the terrarium once a week is all that it takes to maintain a healthy, happy herp. While this may occasionally be the case, more often than not, further attention to nutrition and long-term maintenance protocols of feeder crickets are needed to raise and breed exceptionalreptiles and amphibians.

When adequately cared for, crickets of any type provide an excellent dietary staple for many herp, invertebrate, and mammal species.  While readily available, it is important to ensure that all crickets are well cared for and properly fed prior to being offered to any animal as prey.

Ample space, a proper substrate, and appropriate food and water sources are the keys to maintaining feeder crickets of any quantity.  A little bit of foresight, planning, and effort on our part will ensure that our cricket-eating counterparts receive a nutritionally sound diet and live long, happy lives.

Dangerous Discussions: Part Two – November 2012

The Reptile Times

By Kevin Scott

In Part I of Dangerous Discussions I gave an overview of the definitions of and differences between poisons, toxins and venom. In Part II, I will go into greater detail in describing what toxins and venoms are and where they occur in nature. Of course, it would be impossible to talk about more than a handful of occurrences, so I decided to choose those that I find most interesting.

Toxins

Toxins are organic molecules that are produced via biological pathways and are often used as defense mechanisms by animals. As mentioned in Part I, amphibians secrete substances that are toxic to bacteria and fungi, as the external part of their immune system. Some amphibians also secrete substances that are toxic to predators in order to prevent becoming prey. Tomato frogs and toads, for example, secrete thick milky substances that serve as irritants to potential predators. Arrow Frogs, as discussed in Part I, also secrete toxic compounds, these often being far more toxic than any produced by other amphibians.

The most potent of these toxins are steroid alkaloids, but nearly all of them are neurotoxic. Batrachotoxin is the most toxic of these, but other common compounds include epibatidine, histrionicotoxin and pumiliotoxin. If you are familiar with the arrow frogs, you can see the names of a few species in the names of these molecules. Batrachotoxin targets sodium ion channels, while epibatidine and histrionicotoxin target nicotinic acetylcholine receptors, and pumiliotoxin targets calcium ion channels.

Some, but not all, of these substances are actually produced by the frogs themselves. Many of the more toxic compounds, however, are actually produced downstream in the food chain. Pyrrolidines like epibatadine, and piperidines that are present in species found in the genera Oophaga and Ranitomeya, and Ameerega, Dendrobates and Ranitomeya (Lötters et al 2007), respectively, come from the ants that they eat.

Being that invertebrates and plants are the sources of these toxins, it is not surprising that it is not only the arrow frogs that possess them. Mantellas, the Arrow Frog’s Malagasy counterpart in terms of parallel evolution, also possess some of these toxins. One advantage of the fact that these frogs get this defense from their food items is that they are not nearly as toxic in captivity as they are in the wild.

Another frog that we commonly see in captivity, the Fire Walking Frog (Phrynomantis bifasciatus), also has toxins that can be used as a defense toward predators. This toxin’s identity is not known, but wild caught specimens can cause a burning sensation on the skin of a human, and it is strong enough to cause cardiovascular arrest in other frogs.

fire walking frog

The fire walking frog secretes a substance that can cause intense burning sensations in humans, and death in other amphibians.

Venoms

There are many animals that produce venoms, including spiders, scorpions, marine invertebrates, fish, snakes, lizards and even mammals. Of these, a good handful can be found in the reptile industry.

Venoms are made up of mixtures of low-molecular-weight proteins, mucus, salts and organic compounds that include oligopeptides, nucleotides and amino acids (Colis 1990). This mixture can serve a variety of functions that include defense, prey submission and pre-digestion. Some of the types of venom are as they follow: neurotoxins cause neuromuscular paralysis that can result in immobilization and death; presynaptic neurotoxins block the release of the physiological transmitter acetylcholine, destroying the nerve terminal, and postsynaptic neurotoxins competitively inhibit binding of acetylcholine, preventing the transmission of nerve impulses across the synaptic gap; haemotoxins destroy red blood cells, and extreme cases can lead to renal failure; myotoxins damage muscles, especially respiratory muscles; cytotoxins destroy tissue, and these can aid in pre-digestion; nephrotoxins damage the kidneys (O’Shea 2005).

While the toxins that we have discussed in frogs are passively delivered, venom is delivered with an active delivery system. Special apocrine glands are connected to or in the vicinity of specialized hollow teeth or fangs, grooved teeth or a stinger (in the cases of the reptiles, tarantulas and scorpions that are common in the industry) that act as a penetration device that allows the venom to be administered.

vine snake

The fang of this vine snake can be seen within the red patch of gums behind the eye.

The most advanced delivery systems utilize fangs as an application mechanism. These fangs are specialized hollow teeth, through which the venom is delivered. These are used by vipers (including rattlesnakes) and elapids (including cobras, sea-snakes and kraits). Vipers have long, movable fangs that can be used to alternately progress, ‘walking’ a prey item down during feeding. When not in use, these fangs fold inward, allowing the mouth to close. Elapids are also front-fanged, but they generally have shorter, fixed fangs.

Only relatively few colubrids are venomous, but the ones that are have grooved teeth toward the back of the skull, which is known as being rear-fanged. These teeth are located below or behind the eye socket, and below a specialized salivary gland know as a Duvernoy’s gland, which secretes a toxic saliva that is used in subduing prey (O’Shea 2005).

While they may outwardly appear similar, the fangs of a tarantula or centipede are actually not teeth at all. Rather, they are chelicerae. Chelicerae are pointed appendages that are found in all members of the subphylum Chelicerata, that are used for grasping food or for defense. In spiders and venomous myriapods the chelicerae are hollow, and are used to inject venom from the connected venom gland.

fangs

The chelicerae of tarantulas, spiders and centipedes can be quite large, and are used for grabbing and envenomating prey items, as well as for defense purposes.

Scorpions have a pretty unique venom delivery system known as a telson, or stinger. At the end of the tail, a specialized anatomical development contains both the venom gland and the sharp point used for injection.

scorpion

The telson of a scorpion contains the venom gland and delivery system in one specialized evolutionary development.

Conclusions

Although there are many other animals that are capable of delivering venom and the systems with which venom is delivered are far too complex to discuss in any depth here, I hope that the topics discussed here were enlightening. Furthermore, I hope that the content was deep enough to hold the majority of the readers’ attention, but straight forward enough so that no reader was excluded due to complicated writing.

O’Shea, Mark. 2005. Venomous Snakes of the World. Princeton: Princeton University Press.

Polis, Gary A. 1990. The Biology  Of Scorpions. Stanford: Stanford University Press.

Lötters, Stefan, Karl-Heinz Jungfer, Friedrich Wilhelm Henkel and Wolfgang Schmidt. 2007. Poison Frogs: Biology, Species and Captive Care. Frankfurt: Edition Chaimaira.

Dangerous Discussions: Part One – October 2012

The Reptile Times

DANGEROUS DISCUSSIONS

PART I

By Kevin Scott

Over the last couple of months, I’ve had the opportunity to discuss with various people the differences between poisons, toxins and venoms a surprising number of times. Having studied chemistry, carried out research in a biochemistry and molecular biology laboratory, and having worked in the reptile industry for close to a decade, I find the topic especially interesting when it pertains to herpetofauna.

Depending on whom you ask, the precise definitions for poison, toxin, and venom will differ slightly. There are, however, major differences between these terms, and often the terms are erroneously interchanged. The following is a brief discussion of these differences. Let’s start off by taking a look at and comparing definitions from The Oxford English Dictionary and Stedman’s Concise Medical Dictionary.

Oxford English Dictionary

Stedman’s Concise Medical Dictionary

Poison

A substance that, when introduced to or absorbed by a living organism causes death or injury. Any substance, either taken internally or applied externally, that is injurious to health or dangerous to life.

Toxin

An antigenic poison or venom of plant or animal origin. A noxious or poisonous substance that is formed or elaborated during the metabolism and growth of certain microorganisms and some higher plant and animal species.

Venom

Poisonous fluid secreted by animals such as snakes and scorpions and typically injected into prey or aggressors by biting or stinging. A poisonous fluid secreted by snakes, spiders, scorpions and other cold-blooded animals.

POISON

According to the way that we have defined these terms here, the word poison behaves as sort of an umbrella term for things that can harm biological systems. Poisons include substances that range from household cleaners and pesticides to large organic molecules found in frogs and protein complexes found in snake venom. While the small, brightly colored South American dart frogs are commonly called Poison Frogs, or Poison Arrow Frogs (family Dendrobatidae), it is generally considered incorrect to refer to a venomous snake as a poisonous snake (I will explain why in a moment), although this happens rather often.

TOXINS & VENOM

According to these definitions, a toxin is a type of poison that is produced through a biological pathway. Although this particular medical dictionary’s definition does not make it explicit, toxinologists generally agree that toxins must be taken into the body by absorption or consumption. Venoms, in contrast, must be ‘injected’ into the body by way a specially evolved mechanism, for instance, a stinger or fangs. (I use the word ‘injected’ loosely here, more on this in part II).

In addition to the differences in the mode of application, toxins and venoms are comprised of substances that are inherently different from one another. Toxins tend to consist of comparatively simple organic molecules while venom is usually comprised of an array of peptides and proteins that possess enzymatic activity. In general, venoms are extremely complex mixtures of different compounds while toxins are chemically well defined, pure, and homogenous substances (Mebs 2002).

All amphibians secrete ‘toxic’ substances through their skin that act as anti-bacterial and anti-fungal agents to help them avoid contracting illnesses (Clark 2007). Many species secrete more potent compounds as anti-predatory mechanisms. A particularly well-characterized group is the Arrow Frogs. Several species belonging to this group possess extremely potent toxins, many of which are alkaline steroids. The frogs use these compounds as a defense, and the mechanism through which they work are part of the definition of what a toxin is. Because there is no delivery system for these compounds, they must be consumed by a predator in order for them to be employed. Venom is usually secreted from specialized gland or tissue and is subsequently stored in specialized sacs until it is used. Technically venom can be referred to as being toxic or poisonous, but an animal, a snake for example, that is venomous, is not poisonous, because it wouldn’t harm you to eat it.

ETYMOLOGY

The origin of words is a topic that I find interesting and illuminating. Sometimes you can quickly see the Latin or Greek root of a word just by looking at it, but sometimes the derivation is not immediately obvious. The origin of the word toxin for example, I found surprising.

Poison

Comes from Middle English (probably 15th century) denoting a harmful medical drink, which comes from Old French poison, a potion or poisonous drink (14th century), previously simply a drink (12th century), but originally from Latin, potare, to drink.

Toxin

Comes from the Latin toxicus or toxicum, meaning poisoned or poison, respectively, from the Greek wordtoxikon, or (poison for) arrows, from the Greek toxon, or bow. I found it interesting that the source of the word toxin comes from poisons that were extracted from plants and invertebrates to coat the tips of arrows by ancient Greeks and Romans. The Poison Arrow Frogs obviously got their common name because theirtoxins were used for the same purpose.

Venom

Comes from Middle English, from the Old French venim, a variation of venin from an alteration of the Latinvenenum, or poison.

CLOSING REMARKS

In closing, I would like to point out that I am by no means offering precise definitions for any of the terms used. In fact, I would go so far as to argue that there are no watertight definitions for any of these words. For one thing, biology and biochemistry are so incredibly complex that it is near impossible to precisely define these things by placing them neatly into some well-defined little boxes, there always seem to be exceptions to every rule. Language is always changing and words usually have more than one meaning, so even a precise definition can be open to interpretation. The language discussed here is only relevant within the English language, but there are at least thirteen dialects of English, each with its own differences from modern American English.

When setting out to writing this article I had two points in mind:

  1. To explore some of the fascinating issues that arise when language is used to describe biological systems. Language is inherently obscure and biology is inherently complex. I feel that both are important to understand and interesting to study.
  2. To clear up some of differences between terms in an attempt to at least tighten up the definitions already in place. Even though biology always seems to offer exceptions, we can at least attempt to avoid some of the common errors in terminology.

In part I of this article I have played with the etymology of poisons, toxins, and venom. In part II of this article I will probe deeper into the biology and chemistry of toxins and venom and the evolutionary impact on delivery systems, and I will discuss various types of each.

Mebs, Dietrich. 2002. Venomous and Poisonous Animals: A Handbook for Biologists, Toxicologists and Toxinologists, Physicians and Pharmacists. Stuttgart: Medpharm.

Clark, BT. 2007. “The Natural History of Amphibian Skin Secretions, Their Normal Functioning and Potential Medical Applications.” Biological Reviews. (3):365-379.