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Animalia, biology, Conservation, education, endangered, IUCN Red List, nature, reptile, species, wildlife
Endangered Species series main post.
The reptiles are a grouping of several vertebrate orders which are largely characterised by having ‘scaly’ skin, leathery-shelled amniotic eggs and breathing air. They are also generally exothermic, utilising their environment to raise and maintain their body temperature (hence ‘cold blooded’), though there are exceptions such as Leatherback sea turtles (Dermochelys coriacea) which can maintain a body temperature several degrees warmer than the surrounding water.
There are four extant orders of reptiles: Crocodilia (crocodiles, alligators, etc.), Sphenodontia (tuataras), Squamata (lizards, snakes, etc.) and Testudines (turtles and tortoises). These four groups collectively contain over 8,500 species (over 90% of which belong to the order Squamata; there are only 2 sphenodontids) which range in size from the dwarf gecko (Jaragua Sphaero) at 1.6 cm and 120 milligrams to the Komodo dragon (Varanus komodoensis) at up to 10 feet long and 80+ kilograms. Of course even the Komodo dragon would have been dwarfed by some of its long-extinct dinosaur relatives.
[1] Tudge, C. (2000). The Variety of Life. Oxford University Press.
[2] Zootaxa: Reptiles. [link]
Crocodylia
Chinese alligator (Alligator sinensis)
The Chinese alligator is an inhabitant of the lower reaches of that much abused water-course, the Yangtze river (Anhui, Jiangsu and Zhejiang Provinces), which is home to a number of endangered taxa and was home to the recently-declared-extinct Yangtze river dolphin (Lipotes vexillifer), or ‘Baiji’. While generally amphibious in habits, A. sinensis is dependent on terrestrial nesting, basking and burrowing sites. The wild population is fragmented over a small area of occurrence. There are approximately 200 adults remaining.
[1] Crocodile Specialist Group 1996. Alligator sinensis. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.3
[2] Britton, A. (2009). Alligator sinensis (Fauvel, 1879). Crocodilian species list. [link]
Siamese crocodile (Crocodylus siamensis)
Previously common across much of southern Asia, the Siamese crocodile has been extirpated from the majority of its former range. Indeed, it is possible that the species is no longer present in many areas which it is currently believed to inhabit. Current population levels are unknown; the species is threatened by habitat destruction, hunting and persecution.
[1] Crocodile Specialist Group 1996. Crocodylus siamensis. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.3
[2] Britton, A. (2009). Crocodylus siamensis (Schneider, 1801). Crocodilian species list. [link]
Squamata
Monte Cristo arboeral alligator lizard (Abronia montecristoi)
The species which comprise the genus Abronia are collectively and commonly known as alligator lizards due to their wedge-shaped heads and pseudo-crocodilian morphology. A. montecristoi is native to El Salvador and Honduras where it typically inhabits cloud forests. Like many inhabitants of such ecosystems, A. montecristoi is threatened by habitat loss and climate change. Little is known of the species ecology or population levels.
[1] World Conservation Monitoring Centre 1996. Abronia montecristoi. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.3.
[2] McCranie, J.R., Wilson, L.D. (1999). Status of the Anguid Lizard Abronia montecristoi. Journal of Herpetology, 33(1): 127-128.
Smith’s dwarf chameleon (Bradypodion taeniabronchum)
B. taeniabronchum is a little-known inhabitant of South African montane fynbos (Western Cape natural shrub/heathland). First described in 1831, the species is adept at avoiding detection due to its facility for impromptu crypsis and small size (<20cm). Little is known about the species ecology or population size.
[1] World Conservation Monitoring Centre 1996. Bradypodion taeniabronchum. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.3.
[2] Tolley, K.A., Burger, M. (2004). Distribution of Bradypodion taeniabronchum (Smith 1831) and other dwarf chameleons in the eastern Cape Floristic Region of South Africa. African Journal of Herpetology. 53(2): 123-133. [available online]
Image © Devi Stuart-Fox and Adnan.
Lacépède’s ground snake (Liophis cursor)
L. cursor is a colubrid species restricted to the 0.2km2 Caribbean island of Rocher du Diamant. Like other Liophis species, L. cursor is entirely terrestrial, hunting its prey in moist habitats. Until recently, the species could be found on the island of Martinique. However, since the introduction of the small Asian mongoose (Herpestes auropunctatus), L. cursor populations on Martinique have suffered dramatic declines and the species is probably no longer present.
[1] Breuil, M. 1996. Liophis cursor. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.3
[2] Henderson, R.W., Bourgeois, R.W. (1993). Notes on the diets of West Indian Liophis (Serpentes: Colubridae). Caribbean Journal of Science. 29(3-4): 253-254. [link]
[3] Henderson, R.W. (1992). Consequences of predator introductions and habitat destruction on amphibians and reptiles in the post-Columbus Westy Indies. Caribbean Journal of Science. 28(1-2): 1-10. [link]
Phelsuma antanosy
P. antanosy is a small gecko (~10cm) which inhabits two small, low-altitude coastal forests in the Tolagnaro region of Madagascar. The two populations are split into several sub-populations which inhabit bounded by forest fragments. One inhabited forest fragment in Sainte Luce will almost certainly be lost to an ilmenite mine. While the species may be relatively common in these forests (this is purely hypothetical), their restricted distribution (~9km2), a decline in habitat quality and habitat destruction. It is especially susceptible due to its reliance on two species of tree, both of which are heavily exploited resources.
[1] Jenkins, R., Randrianantoandro, C. & Ramanamanjato, J.B. 2007. Phelsuma antanosy. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.3.
Anegada ground iguana (Cyclura pinguis)
This large-bodied iguana was once common across Puerto Rico but is now predominantly restricted to Anegada Island, the Virgin Islands. Between 1968 and 1991, its population density fell from 2.03/ha to 0.36/ha; based on recent surveys and estimates, there are only 164 individuals remaining on Anegada. Two founder populations have been established on associated islands (Necker and Guana) but even taking these populations into account, the total number of individuals is approximately 200. The species is threatened by habitat alteration by introduced grazers and predation by introduced carnivores.
[1] Mitchell, N. 1996. Cyclura pinguis. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.3.
[2] Mitchell, N. (N/K). Anegada Island iguana. IUCN Iguana Specialist Group. [link]
[3] IUCN (2010). Anegada iguana, Cyclura pinguis: 2006 – 2010 species recovery plan. IUCN. [link]
Image © Glenn Gerber.
El Hierro giant lizard (Gallotia simonyi)
This particularly large wall lizard grows up to 60cm in length (a large proportion of which is tail) and is found on the island of El Hierro in the Canary Islands. Once relatively abundant, predation by introduced species and over-collection resulted in population declines and fragmentation. The declines had halted by the time of the last report (2008) but control of feral cats ceased in 2002 which may result in resumed declines. Several populations have been reintroduced to neighbouring islands. Nevertheless, only 300 – 400 individuals remain.
[1] Jose Antonio Mateo Miras, Valentin Pérez-Mellado, Iñigo Martínez-Solano 2008. Gallotia simonyi. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.3.
[2] ARKive.org. Hierro giant lizard (Gallotia simonyi). ARKive.org. [online]
Bermuda rock skink (Plestiodon longirostris)
P. longirostris is the only terrestrial vertebrate endemic to the archipelago of Bermuda. Habitat loss to agriculture and residential developments has resulted in the decline of this once common species. The impacts of habitat development are exacerbated by invasive species and pollution. Though the species currently inhabits several islands, Southampton Island is believed to be home to the only viable sub-population (~400 animals).
[1] Conyers, J. & Wingate, D. 1996. Eumeces longirostris. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.3.
[2] Davenport, J. Hills, J., Glasspool, A., Ward, J. (2001). Threats to the Critically Endangered endemic Bermudian skink Eumeces longirostris. Oryx. 35:332-339.
Image © Brian Gratwicke.
Golden lancehead (Bothrops insularis)
This arboreal pitviper is native to the island of Ilha da Queimada Grande, Brazil; an area of less than 0.5km2. While the population is currently stable, the limited area of occurrence and declining fertility amongst the population ensure its place on the Red List.
[1] Marques, O.A.V., Martins, M. & Sazima, I. 2004. Bothrops insularis. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.3.
Image © OAV Marques.
Testudines
Dahl’s toad-headed turtle (Mesoclemmys dahli)
There is little information available on this Bolivar State (Colombia) native. It is known to inhabit forest ponds and brooks where it feeds on molluscs, insects, fish and amphibians. Habitat loss is likely to be the primary threat.
[1] Tortoise & Freshwater Turtle Specialist Group 1996. Mesoclemmys dahli. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.3.
[2] Ernst, C.H., Altenburg, R.G.M., Barbour, R.W. (N/K). Phrynops dahli. Turtles of the World. [online]
Image depicts Mesoclemmys tuberculata.
River terrapin (Batagur baska)
While this species can be found in Malaysia, Indonesia, Bangladesh and India, the fragmented and declining nature of the small sub-populations put it at very real risk of extinction. Threatened on many fronts – overexploitation of adults and eggs, habitat loss, accidental trapping and netting, pollution, siltation, etc. – it is no surprise that populations have plummeted in the last 25 years. The species is sporadically protected across its range.
[1] Asian Turtle Trade Working Group 2000. Batagur baska. In: IUCN 2010. IUCN Red List of Threatened Species. Version 2010.3.
[2] Asian Turtle Conservation Network (2006). Batagur baska. Asianturtlenetwork.org. [online]
Image © Pandiyan V.
Burmese star tortoise (Geochelone platynota)
This species, endemic to Myanmar, is readily identified by the beautiful pattern of yellow lines radiating from central points on its black carapace. This is actually an inverted perception of the true colouration as the lines reflect the colour of the carapace which is covered by dark patterning. While a popular and much sought-after pet, little is known of its wild ecology. Over-collection for the Asian food and medicine market and the international pet trade has resulted in a dramatic decline in numbers. The species – possibly the most endangered tortoise – currently exists in three areas in the wild, two of which are protected areas.
This nocturnal toad inhabits limestone outcrops in Puerto Rico. The species common name is derived from the prominent crests which can be seen above the eyes and towards the tip of the snout. As they breed in seasonal pools, habitat destruction is a severe threat, as are introduced species such as the cane toad (Bufo marinus) which may oust P. Lemur from suitable habitat. There may be as few as 250 mature individuals remaining. 
First described in 1976, L. lorica has been described from four sites in north-east Queensland, Australia. It has been estimated that there are less than 50 mature individuals remaining. Though the species has not been described since 1994, its rainforest habitat has been protected since 1988. A relocation program was undertaken in 2008. The continued decline of this fast-flowing stream specialist may be attributable to disease such as chytridiomycosis.
L. archeyi can be found in the western Whareorino range and eastern Coromandel ranges of Waikato Region, New Zealand; the two sub-populations are geographically isolated. Previously abundant (<1996), the species has experienced an overall population decline of over 80% in the past decade. The most likely threats are predation by introduced mammals and the effects of the chytrid fungus.
, this species is restricted to a range of less than 100km2 in Lubuk Selasi, Sumatra, Indonesia. Despite have a limited distribution, it is apparently fairly abundant therein. Repeated surveys have failed to find specimens elsewhere on the island. Habitat destruction and stream siltation are the primary threats.
The Baw Baw frog takes its name from the 80km2 plateau it inhabits and which lies some 120km from Melbourne, Australia. There has been a marked decline the number of adult males in the population, though no specific cause has been identified. The plateau has been invaded by several alien species; climate change, UV radiation, pollution and disease have been implicated in the declines of other similarly located species (though no such study has been undertaken in Australia).
P. cerigensis is a narrow endemic species restricted to Karpathos Island, Greece. Previously abundant (~1960s), the species has been found in one location; an area of less than 10km2. It is thought that numbers are declining in response to habitat loss and degradation.
H. rosei is endemic to Table Mountain, South Africa, where it inhabits an area of approximately 9km2. Though adults have been observed in travelling across land, the species is nevertheless restricted to the protected land which describes its known range. The primary threat to this species is habitat alteration due to the presence of invasive flora riparian flora.
Xenopus species are unique in exhibiting dodecaploidy. X. longipes was first described in 1991; little of the species ecology is currently known. It is only found in Lake Oku, a 10km2 waterbody in central Cameroon. Though the frog is currently abundant within the lake, the introduction of fish by locals for food would likely result in a swift decline.
This splendid newt is native to a single catchment in Luristan Province, Iran. Due to seasonal extremes, the species aestivates during the summer and breeding during the winter rains. Somewhat unsurprisingly, there is great demand for this species from the international pet trade. Over-collection and habitat loss have driven the rapid fragmentation and decline of the population. It is thought that fewer than 1000 mature individuals inhabit a range of less than 100km2.
A. andersoni is known only from Zacapa Lake and associated tributaries, Michoacan, Mexico. It is a paedomorph, retaining juvenile characteristics when sexually mature (neoteny). The species exists within a range of less than 100km2. Primary threats are overexploitation for food and recently introduced predatory fish.
This species is only known from the Shir-Abad cave and its associated stream 60km east of Gorgan, Iran. Approximately 100 adults are remaining, all of which live within the described range (<10km2). Habitat degradation due to people visiting the cave is the greatest threat to the species.
This long-lived, slow-growing salamander (the common name is misleading) is endemic to Beilun, Zhejiang Province, China where the two remaining sub-populations (one having been extirpated recently) are found within a range of less than 100km2. Their life history leaves the species vulnerable as they do not achieve maturity until their tenth year. The deleterious impacts of habitat destruction, pollution, human encroachment and collection for scientific collections pose the greatest threats. The individual in the photograph is exhibiting the anti-predator posture known as the unken reflex.
There is little information [immediately] available regarding this species. It is found at an altitude of between 2,500 and 3000m above sea level on the Sierra de Juarez, north-western Oaxaca, Mexico. The last record of the species dates from 1999; it may already be extinct in the described locality. Reasons for this decline are unknown; some negative anthropogenic impacts are likely though habitat quality rules these out as primary factors.
B. niedeni is found only on Sagalla Hill, Kenya where it has a known range of less than 100km2. The type locality is isolated from similar habitat and is declining in quality. Where present, B. niedeni is considered to be quite common. Specific threats are not known, though increased flooding, destruction of montane forest habitat and increased pesticide use may have negative effects.
