Heikeopsis tuberculata (Morris & Collins, 1991)

Guinot, Danièle, 2023, A new subfamily classification of the highly diversified Dorippidae H. Milne Edwards, 1837 (Crustacea, Decapoda, Brachyura, Dorippoidea), using morphological, molecular and palaeotonlogical data, with special emphasis on its unique female reproductive system, Zoosystema 45 (9), pp. 225-372 : 360

Heikeopsis tuberculata (Morris & Collins, 1991)

Dorippe (Dorippe) frascone tuberculata Morris & Collins, 1991: 5 , fig. 1a, b.

Dorippe frascone tuberculata – Karasawa 2000: table 1.

Heikea tuberculata – Collins et al. 2003: 200, pl. 1, fig. 5.

Heikeopsi s tuberculata – Schweitzer et al. 2010: 79. — Guinot et al. 2013: 187; 2019: 300. — Sasaki 2019: 7790. — Van Bakel et al. 2020: fig. 10.27. — Schweitzer et al. 2021: 2, fig. 1.5a, b.

REMARKS

Heikeopsis tuberculata , from the Lower Miocene Miri Formation of Sarawak, established without knowledge of the contemporary work of Holthuis & Manning (1990), is one of the few fossil dorippids with a well-preserved ventral part (Morris & Collins 1991: 5, fig. 1a, 1b). Based on examination of the type series (holotype and two paratypes) and better preserved specimens, the new description and figures of Collins et al. (2003: 200, pl. 1, fig. 5a-d, as Heikea japonica ) confirm all the characteristic features of the family Dorippidae , e.g. the clearly recognisable Milne Edwards openings and the curvature of the sternal suture 5/6 including the press-button for pleonal locking. This crab is undeniably a dorippid, with the two typical main carapace grooves: a ‘hepatic furrow’ that corresponds to the precervical groove; and a ‘wide, fairly deep, and broadly V-shaped’ cervical groove (see Interpretation of grooves on the carapace dorsal surface in Dorippidae ). The well-marked posterior rim, described as ‘a broad ridge [that] bounds the deeply sinuous, not concave posterior margin’, is similar to that of the extant Heikeopsis . The thoracic sternum, depicted upside down by Morris & Collins (1991) but correctly oriented by Collins et al. (2003) (see Guinot et al. 2013: 187), was shown by Schweitzer et al. (2021: 2, fig. 1.5b). The shape of the carapace, the sculpted and ornamented dorsal surface and the ridged thoracic sternum are not reminiscent of Heikeopsis japonica ( Figs 1 ; 19 A-D), just as the posterolateral tubercle that becomes a sharp spine in some large adults casts doubt on this generic identification. Furthermore, as the present distribution of H. japonica most probably includes only Japan and the nearby region, it may be preferable to assign it to another genus and species. The holotype of Heikeopsis tuberculata represented by Schweitzer et al. (2021: 2, fig. 1.5a, b), with the correct registration number (NHMUK In. 61853), has a sculptured carapace and ridged thoracic sternum that do not conform to the material assigned to H. japonica by Morris & Collins (1991) and Collins et al. (2003), and thus clearly correspond to another genus, most likely in Dorippinae n. subfam. (if the anterior part of the carapace is proven to be narrowed).

Figures

FIG. 1. — A typical dorippid crab, Heikeopsis japonica (von Siebold, 1824), the iconic ‘samurai crab’ known in Japan as ’heike-gani’, whose carapace looks like a human face: A, the species represented by De Haan (1839: pl. 31, fig. 1, as Dorippe japonica) in Fauna Japonica: top, a female; below, chelae of a male; B, lectotype selected by Yamaguchi & Baba (1993: 300, fig. 90-A.a-2, as Heikea japonica) from type series material labelled “Types, Japan, 1823, Leg. P. H. von Siebold”, RMNH CRUS D 822 (see Fransen et al. 1997: 83); C, ♂ 25.0 × 27.3 mm, ♀ 23.5 × 26.7 mm, Japan, Chaffanjon, 174-96, E.-L. Bouvier det. 1899 Dorippe japonica, dry condition, MNHN-IU-2000-4091 (= MNHN-B4091).

FIG. 19. — Heikeopsinae n. subfam. A-D, Heikeopsis japonica (von Siebold, 1824): A, ♂ 22.5 × 24.3 mm, Japan, Tokushima, SMF 57856: habitus; B, ♀ 23.5 × 26.7 mm, Japan, Chaffanjon, MNHN-IU-2000-4091 (= MNHN-B4091): habitus; C, ♂ 25.0 × 27.3 mm, same data as B: ventral view; D, ♂ 24.2 × 25.4 mm, same data as B and C: thoracic sternum and pleon. E, F,?Heikeopsis aff. japonica, China, seas off Qingdao, ZRC 2002.0491: habitus: E, ♂ 21.9 × 24 mm; F, ♀ 23.4 × 26.4 mm.