Nanosesarma pontianacense (De Man, 1895 )

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 : 96-97

Nanosesarma pontianacense (De Man, 1895) # ( Figs. 29 , 40A )

Nanosesarma pontianacense — Bravo et al. 2021: tab. 2.

Taxonomy: Serène (1967: as N. tweediei ), Dai and Song (1977).

Type: No longer extant: holotype ñ in Naturhistorischen Museums in Lübeck (original text), but original collections destroyed in WWII ( Sabaj 2016).

Type locality: Pontianak, Sarawak, Indonesia.

Distribution: Eastern Indian Ocean to South China Sea: From Phuket ( Thailand) to Singapore, Malaysia, Borneo, Vietnam, and South China ( Serène 1967; Ng and Davie 2002).

Habitat: Intertidal; among oyster clumps on rocks.

Remarks: The present species was recently reported in a press release by the Nature Conservacy, based on specimens collected on oyster reefs at Lau Fau Shan, northwestern New Territories (online resource: https://www.tnc.org.hk/en-hk/what-we-do/hong-kongprojects/a-tiny-crab-in-hong-kong-is-showing-bigpromise-for-oyster-reefs/; accessed March 2020). We herein provide illustrations of specimens previously collected from Tung Chung. The second author has examined specimens from Hong Kong, and they are conspecific with material from Southeast Asia. The types are no longer extant and a neotype will be need to be designated as this peculiar species will to be referred to its own genus at a later date (see also Ng et al. 2008: 224).

Neosarmatium indicum (A. Milne-Edwards, 1868) #

Neosarmatium punctatum — Morton 1976: 105; Soh 1978: 10, pl. 3b; Morton and Morton 1983: 214, fig. 11.4(6) [not Metagrapsus punctatus A. Milne-Edwards, 1873 ].

Neosarmatium indicum — Davie 1994: 43, figs. 1E, F, 4, 17; Bravo et al. 2021: tab. 2.

Neosarmatium smithi — WPW Kwok and Tang 2005: 3, fig. 6.

Taxonomy: Davie (1994), Ng et al. (1997).

Type: Lectotype ò MNHN-B10927 (designated by Davie 1994).

Type locality: Sulawesi, Indonesia.

Distribution: Southeast and East Asia: Indonesia, Singapore, Borneo ( Malaysia), the Philippines to South China ( Davie 2002; Schubart and Ng 2002).

Habitat: Supratidal; under tidal and freshwater influences, in deep burrows on muddy substrates.

Remarks: Material reported as N. punctatum in Soh (1978) was verified to represent N. indicum instead ( Davie 1994).

Orisarma dehaani (H. Milne Edwards, 1853) #

Sesarma dehaani — Stimpson 1858b: 106; Stimpson 1907: 134; SY Lee 1993: 203; TH Lui et al. 2002: app. 2.

Holometopus dehaani — Hill et al. 1975: 77; Hill et al. 1978: 108; Soh 1978: 10, pl. 2d; Morton 1979a: 121; Morton and Morton 1983: fig. 11.4(4).

Sesarma (Holometopus) dehaani — SY Lee and Leung 1999: 61, pl. 2.

Sesarma plicata — Tam and Wong 2000: 125, 2 unnumb. figs.

Chiromantes dehaani — WPW Kwok and Tang 2005: 3, fig. 7; Komai and Ng 2013: 540.

Orisarma dehaani — Bravo et al. 2021: tab. 2.

Taxonomy: Shen (1932 b: as Sesarma ( Holometopus )), Komai and Ng (2013: as Chiromantes ), Schubart and Ng (2020).

Type: Lectotype RMNH D 157, and paralectotypes in RMNH, NHM, NHMD and MNHN (designated by Yamaguchi and Baba 1993; see also Fransen et al. 1997; Komai and Ng 2013).

Type locality: Japan, locality unspecified.

Distribution: East Asia: Coasts of China, Taiwan, Korea and Japan.

Habitat: Supratidal; burrowing along muddy riverbanks or under shades of coastal vegetation.

Remarks: Various authors have noted that Chiromantes Gistel, 1848 was polyphyletic ( Ng and Liu 1999; Ng et al. 2008; Komai and Ng 2013), with the taxonomic value of the form of lateral margin of carapace, i.e., presence or absence of tooth behind extra-orbital angle, as adopted by Serène and Soh (1970) in genera classification, being questioned (as with Perisesarma and Parasesarma , cf. Shahdadi and Schubart 2017). Chiromantes and Pseudosesarma were recently revised by Schubart and Ng (2020), and a number of East Asian species, including the locally present C. dehaani , P. patshuni , Sesarmops sinensis and S. intermedia , have been transferred to Orisarma .

Figures

Fig. 29. Nanosesarma pontianacense (De Man, 1895) (male, 5.3 × 6.4, Tung Chung): A, carapace; B, right chela; C, right cheliped dactylus, dorsal view; D, left P5. All structures denuded.

Fig. 40. A, B, C, E, overall habitus; D, F, ventral view. A, Nanosesarma pontianacense (De Man, 1895) (male, 5.3 × 6.4 mm, Tung Chung); B, Parapyxidognathus ongia Hsu & Shih, 2024 (male, 16.6 × 12.9 mm, Tai Tam); C, D, inset, Hemigrapsus penicillatus (De Haan, 1835) (male, 16.3 × 14.6 mm, Lung Mei); E, F, inset, Hemigrapsus takanoi Asakura & Watanabe, 2005 (male, 19.1 × 16.7 mm, Tung Chung). A and B preserved coloration.