Dardanus dearmatus ( Henderson, 1888 ), 1937

Malay, Maria Celia (Machel) D., Rahayu, Dwi Listyo & Chan, Tin-Yam, 2018, Hermit crabs of the genera Calcinus Dana, Clibanarius Dana, and Dardanus Paul’son from the PANGLAO 2004 Expedition, with description of a new species and a checklist of the hermit crabs of the Philippines (Crustacea: Anomura: Paguroidea), Raffles Bulletin of Zoology 66, pp. 23-65 : 37

Dardanus dearmatus ( Henderson, 1888)

Pagurus dearmatus Henderson, 1888: 58 , Fig. 5 , pl. 6 (Admiralty Islands, type locality); Yap-Chiongco, 1938: 196–197.

Pagurus dermatus – Estampador, 1937: 502; Estampador, 1959: 50 (misspelling of Pagurus dearmatus ).

Dardanus dearmatus – Rahayu, 2000: 386; Asakura & Hirayama, 2002: 223–229, Figs. 7 –10.

Material examined. 1 male SL 5.2 mm ( ZRC), stn PN1, Balicasag I., 9°31.2′N, 123°41.3′E, 50–500 m, v.2004 to vii.2004.

Habitat. Subtidal to approximately 500 m.

Remarks. This is typically a shallow subtidal species (to about 15 m, i.e., Rahayu, 2000) but there are reports of D. dearmatus from 29–46 m in the Admiralty Islands ( Henderson, 1888) or much deeper waters, e.g., 605–915 m in Saya de Malha Bank ( Laurie, 1926). The single specimen from Balicasag Island is also from relatively deep water (50–500 m), and was collected via tangle net.

Cassidy (2005), without further explanation, stated his opinion that Estampador’s (1937) report of D. dearmatus actually refers to D. gemmatus . Estampador’s (1937) specimens could not be located for verification ( Asakura & Hirayama, 2002: 229). Regardless of the identity of Estampador’s material, this report confirms the presence of D. dearmatus in Philippine waters.

Figures

Fig. 5. Lateral view of left third pereopod. A, Dardanus lagopodes (Forskål, 1775). Male SL 9.8 mm, stn N2, ZRC 2015.0489; B, Dardanus lagopodes (Forskål, 1775). Female SL 7.6 mm, stn R1, ZRC 2015.0488; C, Dardanus sanguinolentus (Quoy & Gaimard, 1824). Male SL 7.8 mm, stn R38, ZRC 2015.0491; D, Dardanus balhibuon, new species, holotype. Female SL 14.3 mm, stn R38, NMCR 40109. Scale bars = 1 mm.

Fig. 7. Dardanus balhibuon, new species, holotype. Female SL 14.3 mm, stn R38, NMCR 40109. A, Left cheliped, outer view; B, Left cheliped, inner view; C, Right cheliped, outer view; D, Right cheliped, inner view. Scale bars = 1 mm.