Ranina libyca ( Van Straelen, 1935 )

Pasini, Giovanni & Garassino, Alessandro, 2017, A preliminary review of the fossil species of Ranina Lamarck, 1801 (Decapoda, Brachyura, Raninidae), with systematic remarks, Natural History Sciences 4 (1), pp. 43-72 : 54

? Ranina libyca ( Van Straelen, 1935)

Fig. 8

Raninella libyca Van Straelen, 1935: 113-115 , figs. A-D.

Raninella libyca - Schweitzer et al. 2010: 74.

Ranina libyca - Van Bakel et al. 2012: 209. – Karasawa et al. 2014: 260.

Type material: holotype and repository unknown.

Type locality: Kourkour Oasis , Egypt .

Geological age: Paleocene (Danian).

Examined material: Van Straelen’s original figures.

Description by Van Straelen (1935): “ L’animal est reduit au céphalothorax; les couches supérieures du test ont été enlevées; la région frontale est fracturée, les épines sont réduites à leur partie proximale; tous les appedices sont détruits, les surfaces d’insertion des peréiopodes ont perdu leur individualité; les plastron sternal est fracturé ”.

Literal translation: the specimen preserves just the carapace; the specimens appears as inner cast; frontal region poorly preserved; only the proximal part of the spines is preserved; the pereipods are not preserved; sternum poorly preserved.

Discussion. Though poorly preserved, Van Straelen (1935) ascribed the sole specimen to Raninella A. Milne Edwards, 1862 , without any justification. Later this assignment was confirmed by Schweitzer et al. (2010: 74). This assignment, however, has been called into question by Van Bakel et al. (2012: 209) who ascribed lybica to Ranina , without any justification, assignment confirmed also by Karasawa et al. (2014: 260). Based upon Van Straelen’s description and figures, it is difficult to establish a generic placement for this specimen, lacking all Ranina characters. In conclusion, the inability to recognize the diagnostic characters of Ranina questions the placement of lybica to this genus.

Figures

Fig. 8 -?Ranina libyca (Van Straelen, 1935); Van Straelen’s original figures (Figs. C-D).