Cardiomya minerva, Lima & Oliveira & Absalão, 2020

Lima, Tarcilla Carvalho De, Oliveira, Cléo Dilnei de Castro & Absalão, Ricardo Silva, 2020, Small, rare and little known: new records and species of Cardiomya (Bivalvia: Cuspidariidae) from Brazil, European Journal of Taxonomy 619, pp. 1-20 : 11-13

Cardiomya minerva sp. nov.

urn:lsid:zoobank.org:act:B7AF183B-CE39-4084-A9B1-E0F366458513

Fig. 5 A–F

Diagnosis

Quadrangular shell flank, very short truncated rostrum, posterodorsal margin curved upwards, extending above the umbones; external sculpture composed of six posterior radial ribs, rostrum with commarginal growth lines only.

Etymology

This species is named after the character Minerva McGonagall, from the Harry Potter series of books written by the British J.K. Rowling. The name is employed as a noun in apposition.

Material examined

Holotype

BRAZIL – Alagoas state • [1i]; Maceió, Praia da Avenida ; 10 m depth; 10 Apr. 1990; IBUFRJ 5785 .

Other type material

PORTUGAL • [12v and fragments], syntypes of Cardiomya cadiziana Huber, 2010 [= replacement name for Cardiomya curta (Jeffreys, 1876) ]; off Algarve ; 36°54′00″ N, 8°14′30″ W; 523–684 m depth; USNM 172032 • [ 5v], syntypes of Cardiomya cadiziana ; São Pedro Canyon ; 39°55′00″ N, 9°56′00″ W; 1818 m depth; USNM 172033 • [ 4v], syntypes of Cardiomya cadiziana ; São Pedro Canyon ; 39°42′00″ N, 9°43′00″ W; 1097–2003 m depth; USNM 172034 .

SURINAME • [1v], holotype of Cardiomya surinamensis van Regteren Altena, 1971 ; 06°22.5′ N, 55°10′ W; 20 m depth; RMNH.MOL.55387 .

Description

Shell small (length 4.3 mm; height 3.2 mm). Shell flank quadrangular, umbones raised. Anterodorsal margin forming a shoulder, anterior and ventral and margin rounded, little angulated. Rostrum very short, truncated, posteroventral sinuation shallow, posterodorsal margin curved upwards, extending

above the umbones. External sculpture of six radial ribs on the posterior half of the shell flank; rostrum with commarginal growth lines only.

Geographic distribution

Only known from the type locality.

Remarks

The most similar species to Cardiomya minerva sp. nov. are Cardiomya surinamensis van Regteren Altena, 1971 ( Fig. 5 G–H) and Cardiomya cadiziana Huber, 2010 ( Fig. 5 I–J). These two species can be distinguished from Cardiomya minerva sp. nov. by their trapezoidal shell flank, external sculpture composed of incomplete radial ribs on anterior region of the shell flank. Additionally, C. cadiziana exhibits a shorter rostrum, with several faint radial lines, and straight posterodorsal margin, not extending above the umbones.

Figures

Fig. 5. A–F. Cardiomya minerva sp. nov., holotype (IBUFRJ 5785). A–B. External view, left and right valve. C–D. Details of the posterior radial ribs and the rostrum. E–F. Hinge detail. — G–H. Cardiomya surinamensis van Regteren Altena, 1971, holotype (RMNH.MOL.55387), left valve. G. External view. H. Hinge detail. — I–J. Cardiomya cadiziana Huber, 2010, syntype (USNM 172032), left valve. I. External view. J. Hinge detail. Scale bars: A–B, G–J = 1 mm; C–D = 0.25 mm; E–F = 0.5 mm.