Dardanus arrosor ( Herbst, 1796 )

De Matos-Pita, Susana S. & Ramil, Fran, 2015, Hermit crabs (Decapoda: Crustacea) from deep Mauritanian waters (NW Africa) with the description of a new species, Zootaxa 3926 (2), pp. 151-190 : 159-161

Dardanus arrosor ( Herbst, 1796)

( Fig. 5 )

Cancer arrosor Herbst 1796: 170 , pl. 43 fig. 1.

Pagurus arrosor .— Stebbing, 1908: 22 (lit.).— Barnard, 1950: 423, fig. 79a.

Dardanus arrosor .— Schmitt, 1926: 45, fig. 69B, E, H (comp. D. pectinatus )— Forest, 1955: 90, fig. 19.— Macpherson, 1983: 13 ( Namibia, 117 m).— Ingle, 1993: 55, figs. 17–20 (lit.).— García Raso 1996: 738 (Ibero-Moroccan Gulf, 140–524 m).

Material examined. MU86, 91– 103 m, (1); MU120, 109– 105 m, (5); MU124, 97– 85 m, (1); MU136, 103– 112 m, (2); MU137, 81– 84 m, (3); MU139, 96– 97 m, (3); MU148, 215– 245 m, (2); MU149, 93– 146 m, (1); MU156, 107– 102 m, (1); MU158, 80– 98 m, (2); MU161, 89– 92 m, (1); MU171, 105– 100 m, (1); MU173, 314– 540 m, (1); MU183, 138– 177 m, (1); MU240, 106– 108 m, (1); MU 266, 103 m, (1); MUBV 19, 306 m, (6); MUBV 20, 155 m, (2); MUBV 21, 107– 109 m, (15); MUBV 22, 300 m, (1).

Males: 2.62–16.54 mm, females: 2.72–11.12 mm, ovigerous females: 3.83–5.55 mm.

Habitat. Ubiquitous eurybathic species distributed from coastal detritic bottoms to bathyal muds ( d’Udekem d’Acoz 1999). This species was reported in muddy and sandy-mud bottoms with Isidella and Funiculina off southern Morocco; in muddy coastal shell detritic bottoms with Veretillum off Western Sahara and on mud and sandy mud bottoms in the Banc d’Arguin ( Maurin 1968). Also recorded on ‘sand of shell’, ‘shell remains’ and ‘shell remains Foram.’ off N Morocco ( García Raso 1996) and mainly on muddy bottoms off Namibia ( Macpherson 1983).

This hermit crab was found inhabiting shells of Argobuccinum costatum Born , A. giganteum Lam. , Calliostoma granulatum Born , Charonia nodifera Lam. , Dolium galea Linné [= Tonna galea (Linnaeus, 1758) ], Fussus sp, Mesalia opalina Adams & Reeve , Murex cornutus Linné , Nassa sp., Natica fulminea Gmel. , Sveltia lyrata Brocchi and ‘ Xenophora senegalensis P. Fisher (= mediterranea Tiber )’ ( Forest 1955).

The species was reported associated with many different organisms compiled by Williams and McDermott (2004), to which Schuchert (2008) added the hydrozoan species Hydractinia pruvoti Motz-Kossowska, 1905 (= Podocoryna pruvoti ).

Our material was collected from sand and sandy mud bottoms, inhabiting shells of Ranella olearium (Linnaeus, 1758) , Tonna galea (Linnaeus, 1758) , Fusinus sp., Afer pseudofusinus Fraussen & Hadorn, 2000 , Natica sp., Natica canariensis Odhner, 1932 , Genota sp., Nassarius arcadioi Rolán & Hernández, 2005 , Marginella sp., Persicula cingulata (Dillwyn, 1817) , Bivetiella cancellata (Linnaeus, 1767) , Clavatula sp., Xenophora crispa (König, 1825) , Calliostoma sp. and Natica monodi Marche-Marchad, 1957 . One specimen was found in a shelter of the sponge Suberites sp.

As epibionts over the shells we found the hydrozoan species Hydractinia sp., Mitrocomella polydiademata (Romanes, 1876) and Clytia paulensis (Vanhöffen, 1910) , one sponge of the family Raspailiidae , the actiniarian Adamsia palliata (Fabricius, 1779) , some bivalves of the family Anomiidae , some Serpulidae polychaetes and the bryozoans Hagiosynodos sp, and Hippoporidra picardi Gautier, 1962 .

Distribution. Evenly distributed in the E Atlantic from the Bay of Biscay to South Africa, including the Azores, Madeira and Canary Islands and the Mediterranean Sea ( d’Udekem d’Acoz 1999), but also reported in the Indo-Pacific, Japan, Taiwan and New Zealand ( Asakura 2006; Yaldwyn & Webber 2011).

Subsequent records of this species fit well in this distribution ( Maynou and Cartes 2000; Abelló et al. 2002; García Raso & Manjón-Cabeza 2002; Pipitone & Arculeo 2003; Ates et al. 2006; Fanelli et al. 2007; Pipitone & Vaccaro 2011; Muñoz et al. 2012).

For this species the reported depth range extends from 5–750 m ( d’Udekem d’Acoz 1999) and our material was collected from 81–84 m to 314–540 m depth.

Remarks. Our specimens agree with those described by Ingle (1993). Faded specimens of Dardanus arrosor can be easily differentiated from D. pectinatus (Ortmann, 1892) by the longitudinal depression on left pereiopod 2 propodus lateral face present in D. pectinatus (Schmidtt 1926; Forest 1955).

Figures

FIGURE 5. Dardanus arrosor (Herbst, 1796). Adult male, sl: 10.23 mm (MUBV 21; UVIGOBA 3 02032): A, shield and cephalic appendages. B, chelipeds, left, lateral view, right dorsomesial view. Scale A – B, 1 mm.