Thelphusula pueh, Grinang & Ng, 2014

Grinang, Jongkar & Ng, Peter K. L., 2014, Taxonomy of the freshwater crab Coccusa cristicervix Ng & Grinang, 2004 (Decapoda: Brachyura: Gecarcinucidae), with description of a new species of Thelphusula from Sarawak, Malaysia, Borneo, Raffles Bulletin of Zoology 62, pp. 389-395 : 390-394

publication ID	https://doi.org/ 10.5281/zenodo.5353780
publication LSID	lsid:zoobank.org:pub:8493E540-DB48-4CA6-8A73-9D232D5546E1
DOI	https://doi.org/10.5281/zenodo.5451321
persistent identifier	https://treatment.plazi.org/id/F6BD9559-7E88-4785-9413-7811F16D1862
taxon LSID	lsid:zoobank.org:act:F6BD9559-7E88-4785-9413-7811F16D1862
treatment provided by	Tatiana
scientific name	Thelphusula pueh
status	sp. nov.

Treatment

Thelphusula pueh View in CoL , new species

( Figs. 2 View Fig , 3F–J View Fig , 5 View Fig )

Material examined. Holotype: male (16.2 × 12.1 mm) ( ZRC), edge of rice field with swampy vegetation, 26 m above sea level, Kampung Sebako, Pueh, Lundu District , Sarawak, coll. R. Sujang, 29 November 2013 . Paratypes: 6 females (12.6–19.8 mm × 9.9–15.6 mm) ( ZRC) , 4 females (15.8–19.4 mm × 11.4–14.5 mm) ( SBC), same data as holotype ; 1 female (24.1 × 14.8 mm) ( ZRC), in rice field, 31 m above sea level, Kampung Peninjau Lama, Gunung Serambu, Bau District , Sarawak, coll. L. Noun, 10 November 2013 .

Diagnosis. Carapace gently ovate, wider than long, dorsal surface rugose, anterolateral margin convex, epibranchial tooth absent, cervical groove relatively shallow, shallow crista; postorbital cristae weak; H-shaped depression shallow ( Fig. 2A, B View Fig ). Frontal margin deflexed; frontal median triangle absent ( Fig. 2C View Fig ). Median tooth on posterior margin of epistome subtruncate ( Fig. 2C View Fig ).Ambulatory legs not distinctly elongated ( Fig. 2A View Fig ). Major chela with large gap between fingers when closed ( Fig. 2F View Fig ). Male abdomen with somite 6 relatively short, lateral margins distinctly concave ( Fig. 2D View Fig ). G1 terminal segment relatively cylindrical, straight, slightly more than 2 times length of subterminal segment ( Fig. 3F, H–J View Fig ). G2 distal segment short, curved, tip rounded ( Fig. 3G View Fig ).

Colour. In life, the species is dark brown overall on all the dorsal surfaces, with the palm of the chela and sometimes the legs more orange ( Fig. 5A, B View Fig ).

Etymology. The species is named after Pueh, the area where it was collected. The name is used as a noun in apposition.

Remarks. Thelphusula cristicervix and T. pueh , new species, are the only two species of Thelphusula known from western Sarawak. They are easily differentiated from congeners in having a relatively more ovate carapace, a more convex anterolateral margin and more strongly deflexed frontal margin. Their G1s are also superficially similar in shape. Thelphusula pueh can most easily be separated from T. cristicervix by its live colours; with the carapace and legs of T. cristicervix red ( Fig. 4A, B View Fig ), even in small specimens, whereas T. pueh is dark brown ( Fig. 5A, B View Fig ). Thelphusula pueh also has proportionately shorter ambulatory legs ( Fig. 2A View Fig ) (versus longer in T. cristicervix , Fig. 1A View Fig ); relatively shallower cervical grooves ( Fig. 2B View Fig ) (versus distinctly deeper in T. cristicervix , Fig. 1A View Fig ); smooth lateral margins of abdomen ( Fig. 2D View Fig ) (versus uneven in T. cristicervix , Fig. 1D View Fig ); and the outer margin of the G1 subterminal segment is almost straight with the terminal segment more strongly bent ( Fig. 3F, H View Fig ) (versus outer margin of G1 subterminal segment gradually curved with the terminal segment gently bent in T. cristicervix , Fig. 3A, C View Fig ).

Like T. cristicervix , T. pueh has a preference for damp soils and constructs shallow burrows. Its presence in a more open habitat (ricefields) may not be natural.