Tuesday, August 20, 2019

[Arachnida • 2019] Chilobrachys jonitriantisvansicklei • A New Specis of Chilobrachys (Araneae: Theraphosidae) from A Fragmented Forest Patch in the Wet Zone of Sri Lanka [Another from Sri Lanka, After 126 years]

Chilobrachys jonitriantisvansicklei
Nanayakkara, Sumanapala & Kirk, 2019

The mygalomorph spider family Theraphosidae is represented by 980 species in 144 genera globally (World Spider Catalogue 2018). Within the family Theraphosidae sites the genus Chilobrachys. The genus Chilobrachys is found in South and East Asia, with 27 described species to date (World Spider Catalogue 2018). They are ground dwelling spiders, living in burrows lined with silk and other debris (Nanayakkara, 2013, Nanayakkara 2014b). In Sri Lanka the genus is represented by only one species, namely Chilobrachys nitelinus Karsch, 1892 (Pocock 1900a, Nanayakkara 2014b), which also happens to be the type species (species typica) for the genus. 

The new species of Chilobrachys was collected from a fragmented rainforest patch, 347 hectares in extent, located in the Kalutara District, Western Province of Sri Lanka. The specimens were collected from burrows on a soil embankment covered with bryophytes, along the road, with a clear tubular extension made up of soil and other debris. Interestingly, the majority of the known members of the genus Chilobrachys are shades of brown, black or grey, and lack vibrant colours or iridescent sheens on their dorsal surface. The collected specimen on the other hand has a metallic turquoise-blue sheen on all four legs and also an iridescent sheen on the carapace and abdomen. As such, the collected specimen, differs greatly from the other members of the genus, including C. nitelinus, thereby warranting its taxonomy description as a new species. The discovery was part of an ongoing, island-wide study on the mygalomorph spiders in Sri Lanka. Here we describe the second species of Chilobrachys from Sri Lanka after 126 years.

 Family: Theraphosidae, Thorell, 1870 
Genus: Chilobrachys Karsch, 1892 

Chilobrachys jonitriantisvansicklei sp. nov.

Etymology: The specific name refers to co-founder of Idea Wild Joni Triantis Van Sickle, who was kind enough to donate research equipment to the first author and Idea Wild’s continuous support to further research in fauna and flora around the globe.

Ranil P. Nanayakkara, Amila P. Sumanapala and Peter Kirk. 2019. Another from Sri Lanka, After 126 years; Chilobrachys jonitriantisvansicklei sp. nov. (Araneae: Theraphosidae) from A Fragmented Forest Patch in the Wet Zone of Sri Lanka. Journal of British Tarantula Society. 34(2).