Johora erici, Ng, 2020

Ng, Peter K. L., 2020, Revision of the freshwater crabs of the Johora tahanensis (Bott, 1966) species group (Crustacea, Brachyura, Potamidae), with a key to the genus, ZooKeys 994, pp. 1-34 : 1

publication ID	https://dx.doi.org/10.3897/zookeys.994.56810
publication LSID	lsid:zoobank.org:pub:DB1879C9-1904-4320-BE67-4D9F863F6775
persistent identifier	https://treatment.plazi.org/id/881E59DF-ACD2-4E4B-91A1-F9CE77725965
taxon LSID	lsid:zoobank.org:act:881E59DF-ACD2-4E4B-91A1-F9CE77725965
treatment provided by	ZooKeys by Pensoft
scientific name	Johora erici
status	sp. nov.

Treatment

Johora erici View in CoL sp. nov. Figures 1G View Figure 1 , 2G View Figure 2 , 3G View Figure 3 , 4G View Figure 4 , 5G View Figure 5 , 7 View Figure 7 , 11 View Figure 11 , 12G View Figure 12 , 13G View Figure 13 , 14G View Figure 14

Johora tahanensis - Ng, 1995: 249 (part), fig. 1; Yeo et al. 2007: 257 (not Stoliczia (Johora) johorensis tahanensis Bott, 1966).

Material examined.

Holotype: male (38.3 × 32.0 mm) (ZRC 2020.0360), Tasek Temengor, south of Banding, Sungai Halong, Perak, colI. Lim KKP and Tan HH, 1-4 November 1993. Paratypes: 1 male (23.9 × 20.0 mm), 3 females (largest 32.8 × 26.9 mm) (ZRC 1995.268), same data as holotype. Others: 1 male (41.2 × 33.8 mm) (ZRC 1995.0269), in logged forest, Hutan Simpanan, Gunung Basor, Sungai Long, off Sungai Pergau, Jeli, Kelantan, 457 m a.s.l., coll. Davison GWH, August 1986.

Diagnosis.

Adult carapace width to length ratio 1.20-1.22 (Figs 1G View Figure 1 , 2G View Figure 2 , 7A, B View Figure 7 , 12G View Figure 12 ); dorsal surface gently convex in frontal view, not inflated (Figs 3G View Figure 3 , 7C View Figure 7 ); frontal margin sinuous (Figs 2G View Figure 2 , 7B View Figure 7 ); suborbital, pterygostomial and sub-branchial regions rugose, pterygostomial region covered with dense setae (Figs 3G View Figure 3 , 7C View Figure 7 ); epigastric cristae distinct, distinctly anterior to sharp postorbital cristae, postorbital cristae with lateral edges low, joining lateral margin through oblique striae (Figs 2G View Figure 2 , 7B View Figure 7 ); external orbital tooth separated from epibranchial tooth by distinct cleft, epibranchial tooth sharp, distinct (Figs 2G View Figure 2 , 7B View Figure 7 ); anterolateral margin distinctly convex (Figs 2G View Figure 2 , 7B View Figure 7 ); posterolateral margin sinuous or with shallow median concavity, distinctly converging towards gently convex, entire posterior carapace margin (Figs 2G View Figure 2 , 7B View Figure 7 ); posterior margin of epistome with triangular median triangle, lateral margin obliquely sloping (Figs 3G View Figure 3 , 7C View Figure 7 ); outer surfaces of third maxillipeds with dense, long stiff setae; ischium subrectangular, with shallow median oblique groove (Figs 3G View Figure 3 , 4G View Figure 4 , 7C View Figure 7 ); ambulatory legs not elongate, length to width ratio of merus of fourth ambulatory leg 2.7-2.8 (Figs 1G View Figure 1 , 7A View Figure 7 , 12G View Figure 12 ); G1 subterminal segment gradually tapering from broad proximal part to slender distal part, without distinct shelf-like structure along gently concave outer margin; terminal segment gently curved outwards (from median part of sternum), ca. half length of subterminal segment, surfaces with short setae (Fig. 11A-C, E-G View Figure 11 ); G2 slightly longer than G1, distal segment long, about half length of basal segment (Fig. 11D, H View Figure 11 ). Female pleon ovate; somites 3-6 progressively narrower; telson semi-circular (Fig. 13G View Figure 13 ). Vulvae large, on anterior half of sternite 6, adjacent to suture with sternite 5, lateral sternal vulvar cover semi-circular (Fig. 14G View Figure 14 ).

Etymology.

The species is named after the first post-independence director of the National Museum of Singapore (the renamed Raffles Museum) (1967-1973), the late Eric Alfred. A very active freshwater ichthyologist, he collected many of the freshwater crabs in the museum. Eric was a good friend and provided wise counsel and help even years after he stepped down and took over the directorship of the Singapore Maritime Museum.

Remarks.

Ng (1995: 250) commented that the G1 terminal segment of the males from Perak "seems to be somewhat longer and more slender" compared to typical J. tahanensis but incorrectly attributed it to variation. The differences are actually consistent, and it is here recognised as a separate species, J. erici sp. nov. See remarks for J. booliati sp. nov. for differences with allied taxa.

Distribution.

Johora erici sp. nov. is known thus far only from highland streams in northern Perak and Kelantan (Fig. 15 View Figure 15 ).

Conservation.

The conservation status for J. erici is unclear as we have too few specimens, although it appears to have a relatively wide range in the mountains. It should be best categorised as data deficient for the time being (see Cumberlidge et al. 2009).