Biology:Lygodactylus williamsi

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Short description: Species of lizard


Electric blue gecko
Lygodactylus-williamsi.jpg
Male
Female Lygodactylus williamsi.jpg
Female
CITES Appendix I (CITES)[2]
Scientific classification edit
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Family: Gekkonidae
Genus: Lygodactylus
Species:
L. williamsi
Binomial name
Lygodactylus williamsi
Loveridge, 1952
Lygodactylus williamsi distribution.png
Lygodactylus williamsi is restricted to a few square kilometers of Tanzania.

Lygodactylus williamsi is a critically endangered species of lizard in the family Gekkonidae. The species is endemic to a small area of Tanzania. Common names include turquoise dwarf gecko, William's dwarf gecko and, in the pet trade, electric blue gecko or electric blue day gecko.[3]

Illegally wild-caught specimens are widely sold in the pet trade, often falsely promoted as captive-bred. Although L. williamsi breeds in captivity,[4] the young have specific care requirements, making large-scale breeding difficult.[5] A captive breeding project and studbook was initiated by EAZA-registered zoos in 2013.[4]

L. williamsi, as a species, was placed under EU Appendix B protection (December 2014) and EU Appendix A protection (January 2017), and given CITES Appendix I protection in January 2017, as well.[6][7][8][9] The gecko may not be kept or sold in the EU without documentation and permits, renewable every three years, and geckos must now be registered.[6][10][7] Similar restrictions apply in some other jurisdictions.

Population

The survival of L. williamsi is mostly threatened by (entirely illegal) collection for the international pet trade.[3] It is critically endangered and the population is thought to be declining rapidly.[1]

Although trade in wild-caught turquoise day geckos is illegal, wild-caught geckos are commonly sold in pet shops. It is estimated that between December 2004 and July 2009, at least 32,310 to 42,610 geckos were taken by one collecting group, ~15% of the wild population at the time.[3] However, a small number of individuals are working with L. williamsi, fine-tuning proper husbandry to promote the captive-breeding of healthy, hardy animals.[11] Captive-bred animals also do not experience a stressful readjustment period (to captivity) as they were never taken from the wild; the offspring of captive bred geckos will innately be accustomed to human care, as opposed to the shock (and possible death) of truly wild-caught geckos. A standout among modern breeders is Frank Payne (of Living Arts), who has stated that ″...All of my [L.] williamsi offered for sale are captive bred by me in my home, none of the williamsi I have ever owned have been taken from the wild.″[12] Mr. Payne has gone on to produce nearly 1,000 L. williamsi geckos through his home breeding project.[13]

Geographic range

L. williamsi is only found in 8 km2 (3.1 sq mi) of the Kimboza Forest, Ruvu Forest Reserve, Mbagalala and Muhalama at an altitude of 170–480 m (560–1,570 ft).[14] These are located at the foothills of the Uluguru Mountains in eastern Tanzania.[14]

The subpopulation in Kimboza Forest Reserve was estimated at 150,000 adults in 2009. The size of the remaining subpopulations is unknown, but their size is not thought to contribute significantly to the total population.[1] The two known sites outside protected areas are tiny: one consists of 14 Pandanus trees (the rest has been cleared for banana plantations) and the other is equally close to disappearing.[4]

Habitat

In the wild, the turquoise day gecko lives exclusively on the (redlisted endemic)[15] screwpine, Pandanus rabaiensis,[3] mostly in the leaf crown. It only lives on large trees, those with leaves more than 1 m (3.3 ft) long.[16] A single leaf crown will typically contain a single individual, or an adult male, an adult female, and juveniles.[16] It eats small insects and drinks water from leaves. It is also fond of nectar.

Habitat loss

Collectors commonly cut down screwpine trees to reach the geckos living in the leaf crest, destroying the gecko's habitat. Many geckos are thought to die while being shipped to market. The pet trade is likely a worse threat than habitat loss.[3] The gecko is now restricted to the forest in Tanzania and is at risk of extinction in the wild as the forests are cleared.

L. williamsi's tropical forest habitat is also shrinking and fragmenting.[17] Neither of the Catchment Forest Reserves where it occurs is well-protected.[1] The forest is seriously threatened by pet collectors,[3] clearing for farmland, illegal logging, increasingly frequent fires,[1] mining of rubies, tourmaline, rhodolite, gold[16] and dolomite and limestone from outcrops on which the screwpines grow.[1] Invasive trees such as Cedrela are also a threat.[16] There is little forest left unaffected.[17]

Appearance

Female gecko from obliquely above; reddish-bronze-brown back, fading through golden to green at the sides
Females and non-dominant males may be more brown, bronze or green (males are more blue, grey, or black)
Male lizard clinging to glass, form below, showing bright orange belly
Both sexes have orange undersides

Males of L. williamsi are bright blue with heavy black throat stripes, visible preanal pores, and hemipenile bulges. Females range from brown or bronze to bright green, and have little to no black on the throat. Females can easily be confused with juvenile or socially suppressed males that are also green, sometimes with a bluish cast. The underside of both sexes is orange. Colours of individuals vary according to mood and temperature. Males may range from black or gray to brilliant electric blue. Females may range from dark brown to brilliant green with turquoise highlights. Adult snout-vent length (SVL) is 5 to 8 cm (2.0 to 3.1 in).

A Lygodactylus spp. identification guide has been published online by CITES,[18] largely for the use of customs officers (illegal shipments of these geckos are often intentionally mislabelled).[16]

Behavior

Like all geckos of the genera Lygodactylus and Phelsuma, L. williamsi is diurnal. It is bold, active, and social. Males are territorial, and do not generally tolerate the presence of other males.[16] Social gestures include lateral flattening, puffing out of the throat patch, head shaking and head bobbing, and tail-wagging.

Reproduction

Males of L. williamsi court females with lateral flattening, puffing out of the throat pouch, and head bobbing. Two to three weeks after copulation, the female lays a clutch of 1 or 2 pea-sized white, hard-shelled eggs which are glued to a surface in a secure, hidden location. Eggs hatch in 60 to 90 days.

Etymology

The specific name, williamsi, given to the gecko by British zoologist Arthur Loveridge,[19] honours American herpetologist Ernest Edward Williams.[20]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 Flecks, M.; Weinsheimer, F.; Böhme, W.; Chenga, J.; Lötters, S.; Rödder, D.; Schepp, U.; Schneider, H. (2012). "Lygodactylus williamsi". IUCN Red List of Threatened Species 2012: e.T14665363A14665385. doi:10.2305/IUCN.UK.2012-1.RLTS.T14665363A14665385.en. https://www.iucnredlist.org/species/14665363/14665385. Retrieved 12 November 2021. 
  2. "Appendices | CITES". https://cites.org/eng/app/appendices.php. 
  3. 3.0 3.1 3.2 3.3 3.4 3.5 "Watching extinction happen: the dramatic population decline of the critically endangered Tanzanian Turquoise Dwarf Gecko, Lygodactylus williamsi ". Salamandra 48 (1): 12–20. 2012. http://www.salamandra-journal.com/index.php?option=com_docman&task=doc_download&gid=270&Itemid=74. Retrieved 2013-09-17. 
  4. 4.0 4.1 4.2 Maisch H (2013). "Reasons to feel blue". Zooquaria 83: 24.
  5. "Lygodactylus williamsi". http://www.reptile-care.de/species/Gekkota/Gekkonidae/Lygodactylus-williamsi.html. 
  6. 6.0 6.1 Bergmann M (2015). "Neuer Schutzstatus für den Himmelblauen Zwergtaggecko (Lygodactylus williamsi)" (in German). Terrarianer: Das Terraristik-Blog.. http://terrarianer.blogspot.de/2015/01/neuer-schutzstatus-fur-den-himmelblauen.html. Retrieved 2017-04-19. 
  7. 7.0 7.1 "EU Appendix A inclusion" (in en). 2017-02-01. http://eur-lex.europa.eu/legal-content/EN/TXT/?uri=uriserv:OJ.L_.2017.027.01.0001.01.DEU&toc=OJ:L:2017:027:TOC. 
  8. European Commission (2016-04-26). "Seventeenth meeting of the Conference of the Parties - Johannesburg (South Africa), 24 September - 5 October 2016". http://ec.europa.eu/environment/cites/events_en.htm#cop17. 
  9. "CITES Appendix 1 inclusion". 2016-12-16. https://cites.org/sites/default/files/eng/cop/17/CITES_CoP17_DECISIONS.pdf. 
  10. "EU documentation requirements for listed species". http://eur-lex.europa.eu/legal-content/EN/TXT/?qid=1484753629149&uri=CELEX:02012R0792-20150205. 
  11. Payne, Frank J. (September 2015). "Lygodactylus williamsi Care Sheet". https://www.livingartbyfrankpayne.com/_files/ugd/2b35ad_d4d3462b6ff24be9adbee93bc7a467d1.pdf. 
  12. Payne, Frank (2017). "Electric Blue Gecko (Lygodactylus williamsi)". https://www.livingartbyfrankpayne.com/product-page/lygodactylus-williamsi. "Lygodactylus williamsi are a beautiful small day gecko from the remote Kimboza forest in Tanzania. Due to deforestation and overcollection williamsi are critically endangered in the wild. All of my williamsi offered for sale are captive bred by me in my home, none of the williamsi I have ever owned have been taken from the wild." 
  13. Payne, Frank (2017). "Electric Blue Gecko (Lygodactylus williamsi)". https://www.livingartbyfrankpayne.com/product-page/lygodactylus-williamsi. "I have produced and shared more care information on this species than anyone in the world (care videos, podcasts, Reptiles magazine, etc.). All of it is available for free on my website. I have also quite likely produced more of this endangered species than anyone in the world. I have produced well over 1000 at this point!" 
  14. 14.0 14.1 United Nations Environment Programme World Conservation Monitoring Centre (November 2013). Review of Lygodactylus williamsi.. Retrieved 27 October 2015.
  15. Eastern Arc Mountains.; Coastal Forests CEPF Plant Assessment Project (2009). "Pandanus rabaiensis". IUCN Red List of Threatened Species 2009: e.T157993A5180891. doi:10.2305/IUCN.UK.2009-2.RLTS.T157993A5180891.en. https://www.iucnredlist.org/species/157993/5180891. Retrieved 12 November 2021. 
  16. 16.0 16.1 16.2 16.3 16.4 16.5 CITES Proposal for inclusion
  17. 17.0 17.1 Burgess, Neil; Doggart, Nike; Lovett, Jon C. (2002). "The Uluguru Mountains of eastern Tanzania: the effect of forest loss on biodiversity". Oryx 36 (2): 140–152. doi:10.1017/s0030605302000212. 
  18. "How to Identify Lygodactylus williamsi: A photographic Guide to the Turquoise Dwarf Gecko". TRAFFIC (2011). In: Wildlife Trade Handbook. TRAFFIC East/Southern Africa and the Mohamed bin Zayed Species Conservation Fund, Dar es Salaam, Tanzania. 11–17.
  19. Loveridge A (1952). "A startlingly turquoise-blue gecko from Tanganyika". Journal of the East African Natural History Society 20: 446. (cited in the IUCN database as the species authority).
  20. Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). The Eponym Dictionary of Reptiles. Baltimore: Johns Hopkins University Press. xiii + 296 pp. ISBN:978-1-4214-0135-5. (Lygodactylus williamsi, p. 286).
  • UNEP-WCMC Species Database

External links

Wikidata ☰ Q137615 entry