Dardanus jacquesi Asakura & Hirayama 2002

Celia, Maria, Malay, D., Miller, Allison K. & Komai, Tomoyuki, 2021, Hermit crabs (Crustacea: Decapoda: Anomura: Paguroidea) of the Northern Marianas, including new records and an updated checklist, Micronesica 2021 (1), pp. 1-29 : 10

Dardanus jacquesi Asakura & Hirayama 2002

Fig. 4a

Material. 1 male, SL 6 mm (SIO-BIC C14503), Guguan Island , station AKM-GUG-03 ; 1 female, SL 8.5 mm (SIO-BIC C14509), Pagan Island , station AKM-PAG-02 ; 1 female, SL 3.4 mm (SIO-BIC C14502), no station info ; 2 males and 1 female SL 4–9 mm (SIO-BIC C14504), no station info .

Remarks. When alive, the mesial faces of the palms and carpi of the chelipeds were conspicuously reflective, a character that faded upon preservation. Reflective surfaces may function for communication, as has also been reported in deep-water portunoid crabs in the genus Ovalipes ( Parker et al. 1998) . Color patterns otherwise fit closely with South African specimens of D. jacquesi , described by Landschoff (2018). Dardanus jacquesi is very similar to D. dearmatus , but can be differentiated from the latter on the basis of several characters, particularly in the slenderness of the propodus of the left third pereopod ( Asakura & Hirayama 2002). On the basis of this character, and in the stoutness of the chelipeds, the Marianas specimens better agree with D. jacquesi . However, the pleonal plates were not visible in the present female specimens, and the spination on the inner face of the left cheliped is less pronounced than in the type material as described by Asakura & Hirayama (2002).

Figures

Fig. 4. A: Dardanus jacquesi Asakura and Hirayama, 2002, Pagan Island (SIO-BIC C14509). B: Dardanus lagopodes (Forskål, 1775), juvenile, Pagan Island (SIO-BIC C14505). C: Dardanus megistos (Herbst, 1804), between Guguan and Alamagan Islands (SIO-BIC C14244). D: Dardanus pedunculatus (Herbst, 1804), Agrihan Island (SIO-BIC C14212). E: Dardanus sanguinolentus (Quoy & Gaimard, 1824) Saipan Island (SIO-BIC C14507; recently preserved). F: Micropagurus devaneyi McLaughlin, 1986, Saipan Island (UF 7437).