Corallianassa Manning, 1987

Garassino, Alessandro, Pasini, Giovanni, Angeli, Antonio De & Hyžný, MatÚš, 2014, The decapod fauna (Axiidea, Anomura, Brachyura) from the Late Pleistocene of Trumbacà, Reggio Calabria (Calabria, southern Italy), Natural History Sciences 1 (2), pp. 119-130 : 120-121

Genus Corallianassa Manning, 1987

Type species: Callianassa longiventris A. Milne Edwards, 1870 by original designation.

Included fossil species: Corallianassa acucurvata Swen, Fraaije & van der Zwaan, 2001 .

Discussion. In Corallianassa major merus is ovoid, with armed lower margin, either with denticles (e.g. in C. articulata Rathbun, 1906 ; see Rathbun, 1906: fig. 47b and Sakai, 1999: fig. 15d, e) or large spines (e.g. in C. longiventris (A. Milne Edwards, 1870) ; see Borradaile, 1904: fig. 2b). In this respect, it is similar to Glypturus Stimpson, 1866 ( Hyžný & Müller, 2012). With the exception of one species, Corallianassa intesi (de Saint Laurent & Le Loeuff, 1979) , the lower margin of carpus does not possess spines which is typical for Glypturus . Numerous extant species of Corallianassa possess major propodus that are highest around the midpoint, thus having a convex upper margin (see e.g. Rathbun, 1906: fig. 47b; Poore & Griffin, 1979: fig. 26c; Dworschak, 1992: fig. 14a; Sakai, 1999: fig. 16d, 18c). This is not usual for other callianassid genera, although one can observe variation in this character. Corallianassa usually has a rather long dactylus both in major and minor chela. In the major one, it may be nearly as long as the propodus (e.g. Sakai, 1967: fig. 3C; Sakai, 1999: fig. 16d). Many species possess large setal pores at both fingers, sometimes extending on the palm. Major dactylus is robust, curved and without prominent teeth.

Corrallianassa acucurvata described by Swen et al. (2001) from the Maastrichtian of the Netherlands is based on specimens without merus (which is considered taxonomically important, see Manning & Felder, 1991); other characters, however, conforms with the concept of Corallianassa as presented above.

Corallianassa rigoi described by De Angeli & Garassino (2006b) from the Cretaceous of Italy exhibits a long major propodus with upper and lower margins parallel to each other, and with short fingers. This character combination is not typical for Corallianassa . Moreover, C. rigoi possesses an elongate carpus, triangular in outline, which is quite untypical for the genus. No convincing arguments for generic assignment were presented by De Angeli & Garassino (2006b), and we remove the species from Corallianassa . Re-examination of the type material is needed to resolve the generic status of C. rigoi .

? Corallianassa sp.

Fig. 1A

Material and measurements: One right major propodus (MSNM i27900 – hpa: 8 mm; li: 5 mm; lpa: 9 mm); one left major dactylus (MSNM i27910 – ld: 9 mm).

Description: Major propodus slightly longer than high, highest around the midpoint, upper margin convex, lower margin rimmed; index relatively long, slightly shorter than palm; a faint ridge extends along the index and continues onto palm; outer lateral surface of palm covered with large setal pores at the base of the index; index stout, with blunt tip and a blunt tooth at the middle of the occlusal margin. Major dactylus massive and stout, upper margin forms distinct keel, occlusal margin unarmed, tip hooked; large setal pores forming rows extend along outer lateral surface close to the occlusal margin and along inner lateral surface close to the upper margin.

Discussion. The studied specimens show a suite of characters pointing to their generic identity. The propodus has a convex upper margin, its lower margin is rimmed, fingers possess large setal pores, the index is robust, relatively long and has a blunt tooth at its occlusal margin, dactylus is massive and its tip is hooked. Although none of these characters alone can be treated as diagnostic, their combination is quite typical for Corallianassa . In this respect, the studied material shows striking similarities to C. longiventris (see Borradaile, 1904: fig. 2b) and C. martensi (see Sakai, 1984: fig. 3B). The presence of the faint ridge on the dactylus, however, is unusual for the genus. Therefore, we treat the studied material with question mark.

Another possible candidate for the studied material would be Pestarella Ngoc-Ho, 2003. This taxon has not such prominent setal pores on the lateral surface of propodus like Corallianassa . Finally we point out that, if this studied material represents Corallianassa , it would be the first record for this genus in the fossil and extant record from the Mediterranean basin.