Calappa cuspidata ( Guppy, 1909 ) Pasini & Garassino, 2017

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 : 68-69

Calappa cuspidata ( Guppy, 1909) n. comb.

Fig. 19

Ranina cuspidata Guppy, 1909: 6 , fig. 1 (illustrated with anterior down).

Ranina cuspidata - Guppy 1911: 14. – Rathbun 1919: 168. – Glaessner 1929: 361. – De Angeli et al. 2009: 120. – Collins et al. 2009: 75. – Schweitzer et al. 2010: 74. – De Angeli & Beschin 2011: 13. – Van Bakel et al. 2012: 209. – Karasawa et al. 2014: 260.

Type material: holotype and repository unknown.

Type locality: Machipur near Montserrat, Tamana district, Trinidad Island (Antilles, Atlantic Ocean).

Geological age: early Miocene.

Examined material: Guppy’s original figure.

Description by Guppy (1909): “ The carapace is rather evenly convex and the general contour is almost circular, anterolateral angles being formed by four flattened acute spines pointing outwards beyond the general outline of the carapace; these spinose projections are somewhat similar to the foliaceous expansions of R. palmaea from which they differ in pointing outwards instead of forwards; the median portion of the carapace is formed by a round carina which is separated off by moderately deep grooves from the lateral portions, thus dividing the back into three parts, the median part bearing a single row of distant, low, but acuminate tubercles; and each lateral portion two rows of similar tubercles somewhat irregularly arranged. ”

Discussion. Based upon Guppy’s description and figure, it is difficult to determine a generic placement for this specimen, lacking all diagnostic characters of Ranina . Therefore, the inability to recognize the diagnostic characters of Ranina questions the placement of cuspidata within this genus.

However based upon Guppy’s original description and figure, the subcircular outline of the carapace larger posteriorly, the presence of a raised median carina, and the presence of strong spines along the posterior margin fit better some characters of some representatives of the Calappidae .

Though the scarce state of preservation, the sole specimen is tentatively assigned to Calappa Weber, 1795 .

Figures

Fig. 19 - Calappa cuspidata (Guppy, 1909) n. comb.; Guppy’s original figure (Fig. 1).