Terebratulina cailleti Crosse, 1865

Rojas, Alexis, Gracia, Adriana & Patarroyo, Pedro, 2015, Brachiopods from off the San Bernardo Archipelago (Colombian Caribbean), with comments on specific synonymies in Tichosina Cooper, 1977, Zootaxa 3914 (1), pp. 55-63 : 58-59

Terebratulina cailleti Crosse, 1865

( Fig. 2 J–K)

1865 Terebratulina cailleti Crosse , p. 27–30, pl. 1, figs 1–3.

1886 Terebratulina cailleti Crosse—Davidson , p. 26, pl. 5, figs 41–42. 1977 Terebratulina cailleti Crosse—Cooper , p. 99–100, pl. 25, figs 1–16; pl. 28, figs 4–27. non1987 Terebratulina cailleti Crosse—Logan , p. 49–50, pl. 12, figs 14–22. v2009 Terebratulina sp. indet.—Rojas et al., p. 124.

Occurrence. Off the San Bernardo Archipelago, Colombian Caribbean: MARCORAL stations D3 (9° 48.88' N; 76° 12.47' N), D11 (9° 48.884' N; 76° 12.475' W), D12 (9° 47.097' N; 76° 13.286' W), D13 (9° 48.082' N; 76° 12.620' W), D15 (9° 49.546' N; 76° 11.178' W), D16 (9° 50.322' N; 76° 10.320' W), D17 (9° 49.506' N; 76° 9.591' W), D21 (9° 46.594' N; 76° 12.811' W), D28 (9° 46.64' N; 76° 13.86' W), D30 (9° 53.595' N; 76° 10.974' W), D31 (9° 52.926' N; 76° 11.308' W), D33 (9° 51.755' N; 76° 10.572' W), D34 (9° 52.903' N; 76° 10.119' W), D35 (9° 54.010'N; 76° 10.162' W), D37 (9° 48.082' N; 76° 12.620' W).

Material. One dorsal valve, one ventral valve INV BRA 9. A total of 282 conjoined shells available.

Description. External characters: shell small to medium in size (maximum observed length 11.4 mm), elongate-oval in outline, longer than wide, maximum width slightly anterior to midlength; beak suberect, foramen large in size; anterior commissure uniplicate, lateral commissure concave; surface multicostellate and granulated. Internal characters: ventral valve with pedicle collar well developed; dorsal valve with cardinal process small and transverse; loop ring-like in shape, 40% of dorsal valve length, transverse band wide, broad, strongly arched, with a narrow median crest.

Remarks. The available material is quite similar in size, outline shape, foramen size and ornamentation to the species described in Crosse (1865) and Cooper (1977). The cardinalia and loop of our material are consistent with illustrations in both Cooper (pl. 25, fig. 16; pl. 28, fig. 24) and MacKinnon & Lee (2006, fig. 1311–2) of T. cailleti . This form, originally described from the West Indies, is recognized as a common element in the Caribbean and Gulf of Mexico ( Crosse 1865; Cooper 1954, 1977; Asgaard & Stentoft 1984; Logan 1990). In a preliminary report based on limited material of the MARCORAL cruise, Rojas et al. (2009) identified the genus Terebratulina . However, that material was not described or illustrated. The main external difference between the specimens identified here as T. cailleti and T. latifrons is the slightly wider shell in the latter. These two forms are also distinguished from each other by a different surface ornamentation as well as the size of the foramen. The Miocene specimens identified as T. cailleti by Logan (1987, pl. 12, figs. 14–18) in the Mao Formation of the Dominican Republic are small for this species. They have a slightly auriculate shell and may represent a new form. The material studied consisted of empty and complete (soft bodied) specimens.

Figures

FIGURE 2. Brachiopods off the San Bernardo Archipelago, Colombian Caribbean. A – E. Tichosina plicata Cooper, 1977. A – D. INV BRA 5 conjoined shell. A. Dorsal view. B. Lateral view. C. Ventral view. D. Anterior view. E. INV BRA 6, inner view of dorsal valve showing the loop and broad transverse band. 2 F – I. Terebratulina latifrons Dall, 1920. INV BRA 8 conjoined shell. F. Dorsal view. G. Lateral view. H. Ventral view. I. Anterior view. 2 J – K. Terebratulina cailleti Crosse, 1865. INV BRA 9. J. Inner view of ventral valve. K. Inner view of dorsal valve showing the loop. L – Q. Argyrotheca barrettiana (Davidson, 1866). INV BRA 7. L. Conjoined shell, dorsal view. M. Lateral view. N. Ventral view. O. Anterior view. P. Oblique inner view of ventral valve showing the depressions near to the anterior end of the ventral septum. Q. Inner view of dorsal valve. P – Q. SEM photographs. All scales 5 mm.