Diogenes fasciatus Rahayu &amp; Forest 1995
Creators: name: Rahayu, Dwi Listyo
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Malacostraca
Decapoda
Diogenidae
Diogenes
Diogenes fasciatus

description: <i>Diogenes fasciatus</i> Rahayu &amp; Forest, 1995 (Fig. 8B) <i>Diogenes fasciatus</i> Rahayu &amp; Forest, 1995: 388, fig. 1 (type locality: Muara Karang, Jakarta Bay, Indonesia); Rahayu, 1996: 340; Siddiqui, Kazmi &amp; McLaughlin, 2004: 185, fig. 13. <b>Material examined.</b> 96 males, 0.7–2.9 mm, 5 females, 1.8–2.5 mm, 20 ovigerous females, 1.8–2.5 mm (ZRC 2021.0130), Changi, 18 January 1995; 20 males, 2.4–4.2 mm, 12 females, 1.6–2.4 mm, 20 ovigerous females, 1.6–2.9 mm (ZRC 2021.0131), Changi, 16 February 1995; 8 males, 2.3‒5.3 mm (ZRC 2021.0132), DW58, East of Pulau Tekong, 01°25.064′N 104°04.992′E, 10.9–11.3 m, 22 October 2012; 15 males, 1.6–2.2 mm, 4 females, 1.6–2.0 mm, 5 ovigerous females, 1.8–2.0 mm (ZRC 2021.0133), Chek Jawa, 21 September 2001; 1 male, 1.0 mm (ZRC 2021.0134), Pulau Hantu, 7–10 m, 16 December 2012; 1 male, 3.9 mm (ZRC 2021.0135), st. M24, Pulau Ketam, 8 March 2012; 1 ovigerous female, 4.5 mm (ZRC 2021.0136), st. M13, Pulau Ubin, 7 March 2012; 7 males, 4.5–6.0 mm (ZRC 2021.0137), Changi, beach seine, 16 July 1993; 3 males, 3.1–4.2 mm, 3 females, 2.5–3.5 mm, Perak, Malaysia. <b>Colour in life.</b> Shield mottled with dark grey and light brown. Ocular peduncle white with greyish brown blotch on dorsomesial face distally, light brown patch proximally. Antennular peduncle generally greyish brown, with dark brown band on distal margin of ultimate and penultimate segments, flagella white; first to fourth segments and antennal acicle of antennal peduncle greyish brown, fifth segment and flagella white. Chelipeds palm whitish grey; dactyl and fixed finger with tint of light brown, carpi and meri dark brown or dark grey. P2 and P3 dark brown or dark grey, lighter grey dorsally and ventrally on propodi and carpi, with white spot on articulation dactyl, propodus and carpus (Fig. 8B). The general colouration in life varies from yellowish light brown to dark brown or dark grey, but the pattern is the same. <b>Distribution.</b> Pakistan, Singapore, Malaysia, and Indonesia; 0–7 m, inhabit sandy, muddy substrate. <b>Remarks.</b> Among the species in the <i>edwardsii</i> group, this species is readily recognised by an ensemble of characters as follows: antennal peduncles stout, flagellum with abundant setae; left cheliped dactyl broad, flattened, covered with small tubercls; fixed finger outer surface tuberculate and devoid of longitudinal ridge; and palm with row of strong spines on upper and lower margins, at proximoventral angle row of strong spines parallel to carpal articulation, reaching to distal quarter, then continued as longitudinal row/rows of small spines on outer surface. The differences between <i>D. fasciatus</i>, <i>D. avarus</i> Heller, 1865, and <i>D. investigatoris</i> Alcock, 1905b were already discussed by Rahayu &amp; Forest (1995), and the significance of those characters has been confirmed. The flattened dactyl of the left cheliped and the presence of a row or rows of spines on the propodi of P2 and P3 placed <i>D. fasciatus</i> close to <i>D. lophochir</i> Morgan, 1989. But these two species differ in the presence of pronounced ridge on the fixed finger of the left cheliped in <i>D. lopochir</i> (absence in <i>D. fasciatus</i>), the tuberculate crest on the outer face of the palm of the left cheliped is positioned in the midline in <i>D. lophochir</i> while in <i>D. fasciatus</i> this crest is located adjacent to upper margin. Rahayu &amp; Forest (1995) did not mention the presence of row of spines on the dorsal margin of the propodi of P2 and P3 but indicated that the spines on the carpi are present only in the large individual. Siddiqui et al. (2004) stated that these spines are present or absent in their material and that the specimens from Pakistan have one or two rows of spines on carpi, while Asakura (2020) stated that, in the material from Singapore and Thailand, the dorsal margins of propodi of ambulatory legs have a row of spines, and also figured the spines on the dorsal margin of carpi (Asakura, 2020: fig. 11A, C, E). In some specimens in this study, the propodi and carpi of P2 and P3 have one or two rows of spines on the dorsal margin. Additionally, a tiny spine on the dorsodistal margin of the fourth segment of the antennal peduncles was also detected in some individuals. The spines on the mesial margin of the antennal acicle varies from very prominent to moderately large, and one additional spine is sometimes present at the midlength of the lateral margin. The same character was also observed by Asakura (2020) in his specimens. Further study is necessary to confirm that these characters mentioned above are merely attributed to intraspecific variations or interspecific differences.
description: Published as part of <i>Rahayu, Dwi Listyo, 2022, Hermit crabs of Singapore (Crustacea: Decapoda: Anomura: Diogenidae, Paguridae), with description of two new species, pp. 329-363 in Raffles Bulletin of Zoology 70</i> on pages 342-343, DOI: 10.26107/RBZ-2022-0017, http://zenodo.org/record/7174641
description: {"references": ["Rahayu DL &amp; Forest J (1995) Le genre Diogenes (Crustacea, Decapoda, Diogenidae) en Indonesie, avec la description de six especes nouvelles. Bulletin Museum National d'Histoire Naturelle, Paris, 16 (2 - 4): 383 - 415.", "Rahayu DL (1996) Notes on littoral hermit crabs (excluding Coenobitidae) (Crustacea: Decapoda: Anomura) mainly from Singapore and Peninsular Malaysia. Raffles Bulletin of Zoology, 44 (2): 335 - 355.", "Siddiqui FA, Kazmi OB &amp; McLaughlin PA (2004) Review of the Pakistani species of Diogenes Dana, 1951 (Decapoda Anomura Paguroidea Diogenidae). Tropical Zoology, 17: 155 - 200.", "Heller C (1865) Crustaceen. In: Reise der Osterreichischen Fregatte Novara um die Erde in den Jahren 1857, 1858, 1859 unter den Befehlen des Commodors B. von Wullerstorf-Urbair. Zoologischer Theil, Bd. 2, Abt. 3. Kaiserlich-koniglichen Hof- und Staatsdruckerei, Wien, 280 pp., 25 pls.", "Alcock A (1905 b) Catalogue of the Indian decapod Crustacea in the collections of the Indian Museum. Part 2. Anomura. Fasc. 1. Pagurides. Indian Museum, Calcutta, xi + 197 pp.", "Morgan GJ (1989) The hermit crabs (Decapoda: Anomura: Diogenidae, Paguridae) of southwestern Australia, with description of two new species. Records of the Western Australian Museum, 14 (3): 391 - 417.", "Asakura A (2020) Hermit crabs of the genus Diogenes Dana, 1851 (Crustacea: Decapoda: Diogenidae) collected during the Albatross Philippine Expedition, 1907 - 1910, including descriptions of three new species. Publications of the Seto Marine Biological Laboratory, 45: 1 - 4."]}