Table of contents for September 2024 in Practical Reptile Keeping

A new approach to DNA sequencing has resulted in the first chromosome-level genome assembly for the genus Testudo. As with many threatened land turtle species, the Mediterranean spurthighed tortoise (T. graeca) had no complete genome. For the first time though, researchers from the Ecology departments at Miguel Hernández University of Elche (UMH) and the University of Alicante (UA) have successfully sequenced the genome of this species, using the genome of a native American tortoise as a reference. The results will enable the scientific community to support the conservation of these endangered animals. Background and value The Mediterranean spur-thighed tortoise is one of the most iconic land tortoise species in the Mediterranean region. In the Iberian Peninsula, these tortoises have two main populations: one in the southeast, from northern Almería to…

Female sea turtles lay their eggs, cover the nest with sand and then return to the ocean, leaving their offspring to develop and hatch on their own. Faced with a wide and varied range of dangers, ranging from nest predators to rising temperatures, the odds of survival for the vast majority are bleak. Even once hatched and in the ocean, only about one young turtle in 1,000 makes it through to adulthood. Environmental impacts In this regard, size matters during the early stages of life. Larger hatchlings, which can move faster, are more likely to survive because they spend less time on the very dangerous beach sands. Research shows that both air and sand temperatures crucially impact sea turtle hatchlings. Cooler temperatures produce larger, heavier hatchlings with more males, while…

One of the primary goals when it comes to creating naturalistic set-ups for reptiles is to minimise stress and promote a sense of well-being. However, even with optimal environments, stress can still occur. In fact, wild reptiles and amphibians that find themselves in an unfamiliar situation, or confronted by an unwanted encounter with a rival or predator, will also experience stress, demonstrating that this condition is a natural response, not exclusive to those being housed in vivaria. Nevertheless, inadequate husbandry and a misunderstanding of an individual’s specific needs can exacerbate stress in these particular surroundings. What is stress? Despite their reputation for being resilient creatures, reptiles are clearly capable of suffering from stress. But what exactly is this condition? Stress is something which all animals, (and I include us humans…

FEATURE | ANOREXIC SNAKES Although often recommended as good ‘beginner snakes’ because of their calm temperament, ball (royal) pythons (Python regius) have also acquired a less desirable reputation as fussy eaters. I dispute this label though; it’s certainly true that they typically lack the voraciousness of a reticulated python or a boa, but many times, it is our lack of regard for their nature that is the cause of this problem, rather than the snake being selective about its food. Ball pythons are sensitive to their environment, which means that if the husbandry is not perfect for the individual (and yes, different snakes prefer different things, even within the same species), then it may choose not to eat. Certainly, these particular pythons like to feel safe. Tight spaces should be…

FEATURE | GARTER SNAKES One of the first garter snakes I ever encountered in the wild was a common garter snake (Thamnophis sirtalis). This wily serpent was lying quietly coiled under a log in a small triangle of forest near the garden of my childhood home. While dad was planting tomatoes and corn, I was stealing away from the toil to search for crawling things, and a small black and yellow-striped serpent, measuring roughly 50cm (20in), was the fruit of my labours on that particular day. Seizing up the small snake, I quickly discovered that, unlike the relatively mild-mannered kingsnakes (Lampropeltis species) that I was used to catching, this snake resisted capture in a number of ways. It twisted and thrashed around although I was careful to cradle it gently…

A species of giant fanged frog which went unrecognised in the Philippines because it was nearly identical to even larger species has now finally been identified. Researchers from the University of Kansas (KU) have described the new species, which they have named Limnonectes cassiopeia, from the Philippine island of Luzon. Surprisingly, specimens of the new species have been collected a dozen times over the last 20 years, but all were mistakenly thought to be the juvenile version of the well-known, nearly identical (but not too closely related, as it turns out) Luzon giant fanged frog. The function of their fangs “They’re called fanged frogs because the males of some species have large, bony protuberances resembling fangs in their lower jaw—it’s pretty unique,” explains researcher Mark Herr, from KU’s Biodiversity Institute…

Scientists knew that red-backed salamanders (Plethodon cinereus) were abundant in eastern North America, but a recent study found their densities and overall numbers were much higher than expected. The investigation, conducted by the U.S. Geological Survey and many partner institutions including Michigan State University and Penn State University, marks the first time that the figures for this common but rarely seen species have been calculated across the extent of its range. Amazing numbers! The study authors estimate an average of 5,300 salamanders live in every patch of forest corresponding to the size of a football field in the northeast of the continent. Even though each individual is just a mere 7.5cm (3in) long, the sheer number of red-backed salamanders means that they also have some of the highest biomass estimates…

The lasting legacy of that period can still be glimpsed in various stretches of water around the country even today, where discarded turtles are still to be seen. Those who had taken on cute little hatchling red-eared turtles (Trachemys scripta elegans) often watched in horror as their pets continued growing, to the point that they could potentially reach the size of a dinner plate. No longer able to accommodate these turtles by this stage, and with rescue shelters overflowing, so a number of owners decided simply to discard their unwanted pets into ponds and other stretches of water around the country, as their novelty had worn off. Myth and reality It is virtually impossible to get any accurate figures for the numbers of such turtles that were abandoned illegally in…

It has long been known that a select few species of colubrid snake are venomous. The mangrove snake (Boiga dendrophila) and 33 other members of the genus Boiga are well-known venomous colubrids, with the impact of their venom ranging from being a mild irritant to a serious threat to human life if left untreated. Another mildly venomous group of colubrids are the rear-fanged members of the genus Heterodon, also known as the hognose snakes. Certainly, the most infamous venomous colubrid is the much-feared African boomslang (Dispholidus typus), which claims a number of human lives every year throughout its range in Africa. No one thought that garter snakes were part of this venomous sub-group of colubrid snake species. However, in the early 2000s, it was discovered that garter snakes do, in…

Stethoscopes don’t work well on reptiles. Scales interfere with sound transmission from these instruments, and scared tortoises and turtles hide behind their legs, covering their hearts. Picking up a pulse Now however, researchers at the Cornell University College of Veterinary Medicine have discovered that they can consistently measure reptiles’ pulse rate in an easy-to-reach spot on the back of the head, and that pulse rate corresponds to the heart rate in healthy reptiles. The technique requires an ultrasonic Doppler flow detector, which is a common instrument found in most veterinary clinics. “While the area of the body where a python’s heart rate could be detected was well known, a location to obtain a pulse rate had not previously been accurately described,” explains Dr. Nicola Di Girolamo, associate professor of exotic…

FEATURE | AFRICAN GIANT BULLFROG The African giant bullfrog is often nicknamed the pixie frog, thanks to the first part of its scientific name which is Pyxicephalus adsperus. These enormous amphibians can grow to a length of 25cm (10in) in the case of males, and may weigh up to 1.4kg (3.1lb). Unusually in this case, females are smaller, attaining about half the size of the males. In terms of their overall appearance, African giant bullfrogs have stout bodies, large heads and are green in colour, with creamy-white underparts. They have an extensive natural range, being found across much of southern Africa in Kenya, Tanzania, Uganda, Mozambique, Malawi, Zambia, Angola, Zimbabwe, Botswana, Namibia and South Africa. Feared now to be extinct in Eswatini (Swaziland), this species may nevertheless also occur in…

Blue is not a particularly common colour among lizards, especially monitors, making this striking species fairly unique. Its colouration does vary though, depending on both the individual and its surroundings. There is a tendency for black areas to predominate, explaining the alternative common name of blue-spotted tree monitor that is also sometimes accorded to this species. The distribution of the blue tree monitor in the wild is very limited, in that it is only known to occur on the Indonesian island of Batanta, which lies to the northwest of New Guinea. This species was first described as recently as 2001, and its scientific name commemorates Duncan MacRae, who founded the Rimba Reptile Park on the island of Bali. The blue tree monitor is quite small, certainly when compared with other…

The characteristic that defines invertebrates as a group is their lack of a vertebral column and indeed, they have no bones at all to support their bodies. This does not necessarily mean that they are soft-bodied though, as reflected by corals and starfish that are to be found in the marine environment. On land too, a number of terrestrial invertebrates, such as scorpions, are well-protected by a robust body casing. The invertebrates that are widely kept today include members of the phyla Mollusca and Arthropoda. The molluscs, as members of the first group are known, are very widely distributed, occurring not just on land, but also in freshwater areas and the sea. The major subdivision within this phylum consists of the gastropods, which represent slugs and snails. There are some…

Q What attracted you to keeping the Bastimentos pumilios poison dart frogs? A I saw my first Bastis in June 2000, at ‘Frog Day’, an event that was held in San Jose here in California, and it was love at first sight! The contrast between the frog’s white belly and toes and the vibrant red or orange topside to the body, as well as the black specks and spots was simply stunning. Bastis form part of a group known as strawberry poison dart frogs, although not all of them are red in colour! There are a number of different morphs that exist, typically isolated within very localised areas, which helps to explain their diversity in appearance. I set up a vivarium at home which now contains seven Bastimentos pumilios. Three were…