Pseudohelice subquadrata ( Dana, 1851 )

Hsu, Jhih-Wei, Shih, Hsi-Te & Innocenti, Gianna, 2022, A review of the mud crab genus Pseudohelice Sakai, Türkay & Yang, 2006 (Crustacea: Brachyura: Varunidae), with redescription of Cyclograpsus latreillii H. Milne Edwards, 1837, from the western Indian Ocean, Raffles Bulletin of Zoology 70, pp. 94-107 : 96-100

Pseudohelice subquadrata ( Dana, 1851)

( Figs. 1 , 2 )

For other synonyms before 2006, see Sakai et al. (2006).

Chasmagnathus subquadratus Dana, 1851: 251 (type locality: possibly New South Wales, Australia).

Helice leachii — Sakai, 1939: 698, text-fig. 126; Takeda, 1982: 223, fig. 662; Dai et al., 1986: 505, fig. 286(5–6), pl. 72(1).

Helice leachi — Miyake, 1983: 241 (list); Sakai, 1976: 672, textfigs. 370a, b, pl. 228(2).

Helice (Helice) leachii — Dai & Yang, 1991: 553, fig. 286(5–6), pl. 72(1).

Pseudohelice (Pseudohelice) subquadrata — Sakai et al., 2006: 37, figs. 53–59 (part).

Pseudohelice subquadrata — Shih, 2007: 22, figs. 45–48; Sun et al., 2009: 325 ( China: Hainan); Liu & Wang, 2010: 69, 2 unnumb. figs. (Taiwan); Nishigaki et al., 2011: 87, fig. 1E–H (Ryukyus); Komatsu, 2011: 277 (list) ( Japan: Ogasawara Is.); Japanese Association of Benthology, 2012: 203, 1 unnumb. fig.; Shih, 2012: 94, figs. 133–135 ( Taiwan: Dongsha I.); Ko & Lee, 2012: 40 ( Korea); Li & Chiu, 2013: 61 (part), 1 unnumb. fig. (upper left only) (Taiwan); Lee et al., 2013: 106, 2 unnumb. figs. (Taiwan); Pratiwi & Rahmat, 2015: 198 ( Indonesia: Jakarta); Ng et al., 2017: 110 (list); Li & Chiu, 2019: 94, 3 unnumb. figs. (Taiwan); Toyota et al., 2019: 280, 5 unnumb. figs. ( Japan: Ryukyus); Kim et al., 2020: fig. 1B ( Korea); Shih, 2020: 126, figs. 153–155 ( Taiwan: Dongsha I.); Shih et al., 2020: 251, tab. 1; Itoh, 2020: 49, fig. 2 ( Japan: Izu Peninsula); Inui et al., 2021: 138, fig. 2D ( Japan: Sagami Bay).

Pseudohelice quadrata [sic]— Ng et al., 2008: 227 (list).

not Pseudohelice subquadrata —Bouchard, 2009: 6, 28 ( Mayotte) (= Parahelice balssi ( Sakai, Türkay & Yang, 2006)) ; Bouchard et al., 2009: 23, 45 (list) ( Mayotte) (= Parahelice balssi ( Sakai, Türkay & Yang, 2006)) ; Li & Chiu, 2013: 61 (part): 2 unnumb. fig. (upper right= Parahelice daviei ( Sakai, Türkay & Yang, 2006) ; lower= Parahelice pilosa ( Sakai, Türkay & Yang, 2006)) ; Bouchard et al., 2013: 29, fig. 24 ( Mayotte) (= Parahelice balssi ); Poupin et al., 2018: 73 ( Mayotte) (= Parahelice balssi ( Sakai, Türkay & Yang, 2006)) .

Material examined. Australia: 1 male (19.2 × 17.1 mm) , 1 female (20.9 × 18.3 mm) ( QM W19922), Elimbah Creek , Toorbul, SE Queensland, coll. P. Davie, 5 July 1994 ; 2 males (16.4 × 8.8, 20.0 × 17.4 mm), 1 female (14.7 × 12.0 mm) (MNHN-IU-2013-14771 = MNHN-B20874 ), South West Rocks, Trial Bay , New South Wales, coll. 1920 (identified by M. Türkay in 1983 as Helice leachii Hess, 1865 ) . New Caledonia: 2 males (18.8 × 11.9, 23.8 × 20.6 mm) , 1 female (25.5 × 21.7 mm) (MNHN-IU-2013-8633), Nouméa, coll. R. Serène , 10 August 1971 (identified by S.-L. Yang in 1993 as Pseudohelice subquadrata ( Dana, 1851)) . Japan: 1 male (11.3 × 9.7 mm) , 1 female (12.8 × 11.2 mm) (NCHUZOOL 16696), Hiyagon Swamp , Okinawa I., Ryukyus, 20 June 2005 ; 1 male (16.2 × 13.8 mm) (NCHUZOOL 16705), Miyara R., Ishigaki I., Ryukyus, 2 August 2005 . Taiwan: 1 male (13.2 × 11.0 mm) (NCHUZOOL 13218), Wazihwei, New Taipei City, 17 November 1995 ; 1 male (9.5 × 7.9 mm) (NCHUZOOL 16697), Tiaoshih coast, New Taipei City, 25 July 2002 ; 2 females (14.8 × 12.4, 16.8 × 14.3 mm) (NCHUZOOL 16177), Jhuwei, New Taipei City, 1 June 2007 ; 2 males (14.4 × 12.1, 15.9 × 13.5 mm), 2 females (14.7 × 12.2, 17.7 × 15.1 mm) (NCHUZOOL 16178), Jhuwei, New Taipei City, 30 June 2006 ; 2 females (13.6 × 11.5, 16.0 × 13.5 mm) (NCHUZOOL 16181), Houhu R., Taoyuan City, coll. P.-Y. Hsu & Y.-H. Huang, 2 September 2011 ; 1 female (13.4 × 11.2 mm) (NCHUZOOL 15724), Gangnan, Hsinchu City, 19 July 2012 ; 3 males (19.3 × 16.5, 20.4 × 17.6, 20.9 × 18.2 mm) (NCHUZOOL 15723), Sinfeng, Hsinchu County, 31 August 2012 ; 1 male (12.3 × 10.7 mm) (NCHUZOOL 16698), Jhonggang R. estuary, Houlong, Miaoli, 30 May 2014 ; 2 males (12.8 × 10.9, 13.0 × 11.2 mm) (NCHUZOOL 16699), Jhonggang R. estuary, Houlong, Miaoli, 30 May 2014 ; 1 male (12.8 × 10.9 mm) (NCHUZOOL 16180), Dingtouer Shoal, Cigu , Tainan, coll. J.-H. Lee & W.-C. Wang, 23 February 2010 ; 1 female (15.3 × 13.0 mm) (NCHUZOOL 15731), Dingtouer Shoal, Cigu , Tainan, coll. J.-H. Lee & W.-C. Wang, 23 February 2010 ; 1 male (14.9 × 13.0 mm), 2 females (16.2 × 13.5, 17.2 × 14.9 mm) (NCHUZOOL 16718), Dingtouer Shoal, Cigu , Tainan, coll. J.-H. Lee & W.-C. Wang, 23 February 2010 ; 7 males (13.6 × 11.8–17.6 × 15.1 mm), 7 females (14.6 × 12.2–18.0 × 15.1 mm) (NCHUZOOL 16719), Dingtouer Shoal, Cigu , Tainan, coll. J.-H. Lee & W.-C. Wang, 23 February 2010 ; 1 male (16.6 × 14.8 mm), 2 females (17.3 × 14.5, 18.8 × 16.0 mm) (NCHUZOOL 15726), Yanshuei R., Tainan, coll. J.-H. Lee & W.-C. Wang, 9 November 2009 ; 2 males (8.0 × 6.7, 8.1 × 6.9 mm) (NCHUZOOL 16183), Baoli R. estuary, Checheng, Pingtung, 3 September 2011 ; 1 female (12.1 × 10.3 mm) (NCHUZOOL 16184), Baoli R. estuary, Checheng , Pingtung, coll. J.-H. Lee & W.-C. Wang, 1 March 2010 ; 1 male (8.3 × 7.0 mm) (NCHUZOOL 16182), Wanlitong, Pingtung, 20 December 2011 ; 1 male (12.7 × 10.7 mm), 2 females (11.6 × 9.9, 14.5 × 12.4 mm) (NCHUZOOL 15733), Wanlitong , Pingtung, coll. J.-H. Lee, 20 August 2012 ; 3 males (7.8 × 6.6, 10.3 × 8.8, 13.0 × 11.2 mm), 2 females (9.9 × 8.3, 12.1 × 10.3 mm) (NCHUZOOL 16185), Gangkou R. estuary, Hengchun , Pingtung, coll. P.-Y. Hsu et al., 7 November 2018 ; 1 female (16.1 × 13.4 mm) (NCHUZOOL 16706), Dulanwan , Donghe, Taitung, 9 August 2017 ; 1 male (13.7 × 11.8 mm) (NCHUZOOL 15725), Dongsha I., 2 September 2011; 2 males (14.7 × 12.5, 15.6 × 13.1 mm), 2 females (16.6 × 14.0, 16.8 × 14.3 mm) (NCHUZOOL 16176), Dongsha I., 2 September 2011; 1 female (18.2 × 15.4 mm) (NCHUZOOL 16179), Dongsha I., 6 September 2011; 1 male (17.8 × 14.7 mm), 1 female (13.9 × 11.5 mm) (NCHUZOOL 16700), Dongsha I., 22 March 2012; 1 male (11.9 × 10.3 mm), 1 female (15.9 × 12.9 mm) (NCHUZOOL 16701), Dongsha I., 25 May 2012; 2 males (12.6 × 10.9, 15.5 × 13.5 mm) (NCHUZOOL 16702), Dongsha I., 29 May 2012; 1 male (12.6 × 10.8 mm) (NCHUZOOL 16703), Dongsha I., 3 September 2011; 1 male (18.0 × 14.7 mm) (NCHUZOOL 16704), Dongsha I., 5 September 2011; 1 female (17.0 × 14.5 mm) (NCHUZOOL 16716), Dongsha I., 2 September 2011; 1 male (17.2 × 15.1 mm), 1 female (15.3 × 12.7 mm) (NCHUZOOL 16717), Dongsha I., 24 March 2012; 1 male (12.5 × 10.5 mm) (NCHUZOOL 16720), Dongsha I., 3 September 2011; 1 male (15.1 × 12.6 mm), 1 female (14.7 × 12.4 mm) (NCHUZOOL 16721), Dongsha I., 2 September 2011; 1 male (16.0 × 14.1 mm), 1 female (18.1 × 15.1 mm) (NCHUZOOL 16722), Dongsha I., 17 November 2012; 1 male (16.3 × 13.1 mm) (NCHUZOOL 16723), Dongsha I., 22 July 2012. Indonesia: 1 female (5.9 × 5.2 mm) (NCHUZOOL 15722), Gadon Beach, Tabanan, Bali, 22 July 2014 ; 5 females (15.5 × 13.2, 16.4 × 14.0, 16.7 × 14.5, 17.4 × 15.2, 17.5 × 15 mm) (NCHUZOOL 15727); Gadon Beach, Tabanan, Bali, 22 July 2014 .

Diagnosis. Carapace ( Fig. 1A, C ) quadrate, slightly broader than long, 1.18 times as broad as long; surface convex, weakly punctate, granulated, with noticeable groove between epigastric regions. Frontal margin slightly concave. Anterolateral margins with 3 teeth including orbital tooth; last tooth weak, sometimes indistinct. Infraorbital ridge ( Fig. 1E, F ) in both sexes heteromorphic; in male, mesial part with several small rounded or elongated tubercles, followed by well-spaced several large, heteromorphic, elongated and less convex tubercles, lateral part with 1 significantly largest, elliptical and very convex tubercle, and 2–5 large convex tubercles ( Fig. 1E ); in female, mesial part with several dense small rounded tubercles, followed by closely spaced several larger, elongated and less convex tubercles, lateral part with 1 largest and 2–5 larger convex tubercles ( Fig. 1F ); tubercles in lateral part more convex in male, less convex in female. Cheliped palm bulky, almost glabrous; usually unequal in adult male, equal in adult female. Ambulatory legs ( Fig. 1A–D ) slender, anterior margins of merus, carpus, and propodus covered with dense short setae. Male G1 ( Fig. 1G–J ) stout, blunter, distal part relatively flat with small chitinous beak-like structure distally; female vulvae ( Fig. 1K ) with an elongated semi-circular sternal vulvar cover; sunken on inner part.

Colour in life. Varied, from yellowish-brown, orange, olive green, dark green, dark purple to dark grey, with several irregular light brown or white patches on carapace in some individuals. Colour of chelipeds usually lighter (except dorsal margins of palms), often light brown or off-white ( Fig. 2 ).

Ecology. The habitats include mudflats, mangroves, and marginal areas of coastal forest. It is sympatric with some species of Parahelice in Taiwan (Shih et al., 2020).

Distribution. French Polynesia, Samoa, Fiji, New Caledonia, E. Australia, Caroline Is., Guam, Japan (including Ryukyus and Ogasawara Is.), Korea (Jejudo), Taiwan, China (Hainan), Philippines, Indonesia (Sulawesi, Bali, and Lombok) and western Thailand (Surin I., Phang Nga) ( Sakai et al., 2006; this study) ( Fig. 4 ).

Size. The largest male specimen examined is CW 20.9 mm (NCHUZOOL 15723), and female is CW 20.9 mm (QM W19922).

Remarks. Sakai et al. (2006) selected a male specimen (QM W2269) from Sydney as the neotype of P. subquadrata ( Sakai et al., 2006: figs. 53–59). In our study, the specimens collected from SE Queensland (QM W19922) agree with the description in Sakai et al. (2006). This species is similar to P. latreillii but can be distinguished by the structures of the infraorbital ridges, G1s, and vulvae (see Remarks under P. latreillii ; Table 2).

Figures

Fig. 1. Pseudohelice subquadrata (Dana, 1851). A, B, E, G–J, male (19.2 × 17.1 mm, QM W19922); C, D, F, K, female (20.9 × 18.3 mm, QM W19922); A–D in preservative. A, dorsal view of male; B, ventral view of male; C, dorsal view of female; D, ventral view of female; E, left male infraorbital ridge; F, left female infraorbital ridge; G, I, dorsal view of left G1 (horizontally flipped); H, J, ventral view of left G1 (horizontally flipped for comparison with the right G1s of other specimens); K, right vulva.

Fig. 2. Pseudohelice subquadrata (Dana, 1851), colour in life. A, dorsal view, male (15.6 × 13.1 mm, NCHUZOOL 16176, Dongsha I.); B, ventral view, male (15.6 × 13.1 mm, NCHUZOOL 16176, Dongsha I.); C, male (NCHUZOOL 16704, Dongsha I.); D, male (NCHUZOOL 16720, Dongsha I.); E, female (17.4 × 15.2 mm, NCHUZOOL 15727, Bali); F, male (18.0 × 14.7 mm, NCHUZOOL 16704, Dongsha I.); G, burrows of P. subquadrata (Hsinchu County: Sinfeng); H, habitat of P. subquadrata (Hsinchu County: Sinfeng).

Fig. 4. The geographical distribution of Pseudohelice subquadrata (red dotted line) and P. latreillii (blue dotted line). The red solid circles are collection sites of specimens used in this study. The range was established by the additional records from references (see synonym lists for each species). The numbers correspond to the locality of specimens in Table 1. Empty triangles and circles mean the additional records from other references (see list of synonymies). “*” indicates the type locality.