Ilyoplax formosensis Rathbun, 1921

Wong, Kingsley J. H., Ng, Peter K. L., Shih, Hsi-Te & Chan, Benny K. K., 2024, Positive association between PTN polymorphisms and schizophrenia in Northeast Chinese Han population., Zoological Studies 63 (38), pp. 141-149 : 109

Ilyoplax formosensis Rathbun, 1921 # ( Figs. 33 , 41C )

Ilyoplax formosensis — present record.

Taxonomy: Sakai (1939), Shih et al. (2015).

Type: Holotype ò USNM 54473 (original text).

Type locality: near now Lujhou (= Luzhou), New Taipei City, Taiwan (as Washoushu, Taihoku, Formosa).

Distribution: South China Sea and East Asia: Vietnam, South and East China, and Taiwan ( Shih et al. 2015).

Habitat: Intertidal; on muddy substrates under shades of mangroves, with substantial freshwater influences.

Remarks: The type species of Ilyoplax Stimpson, 1858 , I. tenella Stimpson, 1858 , is poorly known. The type material of I. tenella was collected in Whampoa, South China, along the banks of the Canton River, and presumed lost in the Great Chicago Fire in 1871 ( Stimpson 1907; Deiss and Manning 1981). The description of I. tenella (text only) is not to modern standards although the gist seems to fit best with the known morphology of I. formosensis Rathbun, 1921 ( Rathbun 1921; Serène and Lundoer 1974; Shih et al. 2015). The local record of I. tenella was included by Shen (1940a), who cited that of Stimpson (1858b) from Whampoa, with no additional material accessed. Recently we have obtained material of I. formosensis from near Tsim Bei Tsui and reported herein. In the current circumstance, as we cannot be sure about the possible synonymy of these two species, we opt to keep both as distinct entries. This species is a new record for the fauna of Hong Kong.

Ilyoplax ningpoensis Shen, 1940 #

Ilyoplax ningpoensis — Davie 1992a: 349; SY Lee 1993: tab. 1.

? Ilyoplax spp. — So and Lui 2007: 33, 1 unnumb. fig [largest image].

Ilyoplax formosensis — Bravo et al. 2021: tab. 2. [not I. formosensis Rathbun, 1921 ].

Taxonomy: Shen (1940b).

Type: Status unknown.

Type locality: Ningbo, Zhejiang (as Ningpo, Chekiang), China.

Distribution: South China Sea and East Asia: northern Vietnam and South China ( Dai and Yang 1991; Kosuge et al. 1997).

Habitat: Intertidal; on mudflats of rather plastic or fluid substrates.

Remarks: Three sequences from local material identified as “ I. formosensis ” by Bravo et al. (2021; MZ 832065, MZ 832066, MX 832067) were shown to cluster with I. ningpoensis ( MZ 067805, MZ 067807), instead of I. formosensis from South China ( MZ 067854, MZ 067855 and MZ 073755), and Chiayi, Taiwan ( HTS, unpublished data). As such, we consider this record instead represents I. ningpoensis , a species also present in Hong Kong.

Figures

Fig. 33. Ilyoplax formosensis Rathbun, 1921 (male, 8.0 × 5.3 mm, Tsim Bei Tsui): A, carapace; B, maxilliped 3; C, right cheliped carpus; D, right chela; E: pleon.

Fig. 41. Overall habitus. A, B, Baruna sinensis C.G.S. Tan & Huang, 1995 (A, male, 6.2 × 4.7 mm; B, 7.2 × 6.5 mm, Tung Chung); C, Ilyoplax formosensis Rathbun, 1921 (male, 8.0 × 5.3 mm, Tsim Bei Tsui); D, Anomalifrons lightana Rathbun, 1931 (male, 12.7 × 8.9 mm, Tung Chung). All preserved coloration.