Nipponithyris afra Cooper, 1973

Bitner, Maria Aleksandra & Logan, Alan, 2016, Recent Brachiopoda from the Mozambique-Madagascar area, western Indian Ocean, Zoosystema 38 (1), pp. 5-41 : 28

Nipponithyris afra Cooper, 1973

( Fig. 16 ; Table 14)

Nipponithyris afra Cooper, 1973a: 20-21 , pl. 71, figs 1-21. — Zezina 1985: 161; 1994: 48; 2010: 1196. — Hiller 1994: 778. — Laurin 1997: 449, figs 35, 47A-G.

MATERIAL EXAMINED. — Mozambique Channel. MAINBAZA, stn CP 3139, 14 bivalved specimens. — Stn CP 3140, 32 bivalved specimens. — Stn 3141, 11 bivalved specimens. — Stn 3142, 2 bivalved specimens. — Stn CC 3166, 9 bivalved specimens. — Stn CC 3171, 5 bivalved specimens.

North-West Madagascar. MIRIKY, stn CP 3235, 42 bivalved specimens. — Stn CP 3252, 3 bivalved specimens. — Stn DW 3253, 1 bivalved specimen. — Stn CP 3278, 3 bivalved specimens.

DEPTH RANGE. — 243-1195 m.

MEASUREMENTS. — See Table 14.

REMARKS

Of the three species of Nipponithyris so far recorded from modern seas ( Logan 2007; Bitner 2008) N. afra is the only one from the Indian Ocean , occurring off Mozambique at depths of 740-960 m ( Cooper 1973a). This species is characterized by a smooth, sulcate shell, strongly thickened posteriorly. The specimens identified here, which extend the species’ depth range, are generally larger in the mature stage than those described by Cooper (1973a) but are otherwise closely similar. Fig. 16K shows the complete loop in an early terebratelliform stage from MAINBAZA station 3139 and may be compared with one of Cooper’s paratypes shown in his plate 7, fig. 19. In the studied material Nipponithyris afra is one of the commonest species (more than 120 specimens).

Figures

FIG. 16. — Nipponithyris afra Cooper, 1973: A-H, dorsal, lateral and anterior views of complete specimens (MNHN IB-2013-89-91), North-West Madagascar, off Majumga, MIRIKY, stn CP 3252, 850-900 m; I, J, inner views of ventral valve (MNHN IB-2013-92), and tilted (J) to show swollen bases and grooves to accommodate inner socket ridges, SEM, North-West Madagascar, between Majumga and Cap Saint-André, MIRIKY, stn CP 3278, 750-780 m; K, L, inner and oblique views of dorsal valve (MNHN IB-2013-93) to show brachial loop, SEM, Mozambique Channel, Inhambane transect, MAINBAZA, stn CP 3139, 1092-1195 m. Scale bars: A-H, 5 mm; I-L, 2 mm.