Ringicula nitida Verrill, 1872

Gofas, Serge, Luque, Ángel A., Oliver, Joan Daniel, Templado, José & Serrano, Alberto, 2021, The Mollusca of Galicia Bank (NE Atlantic Ocean), European Journal of Taxonomy 785 (1), pp. 1-114 : 70

Ringicula nitida Verrill, 1872

Fig. 29F‒G

Ringicula nitida Verrill, 1872: 16 .

Ringicula nitida – Bouchet 1975: 329–331.

Material examined

GALICIA BANK • 20 sh; 43°00.12′ N, 11°57.67′ W; 1706 m; 29 Jul. 2011; BANGAL 0711 V2; MNCN • 1 sh; 42°56.77′ N, 11°58.53′ W; 1631 m; 2 Aug. 2011; BANGAL 0711 V5; MNCN • 1 sh; 42°59.61′ N, 11°58.41′ W; 1671 m; 7 Aug. 2011; BANGAL 0711 V9; MNCN .

Remarks

Bouchet (1975) considered several deep-sea species of Ringicula as synonyms of R. nitida and, based on this, cited that species from several localities off the northwestern Iberian Peninsula, including GB. However, Mariottini et al. (2000) considered R. nitida as restricted to the Western Atlantic and referred the records by Bouchet (1975) to R. gianninii Nordsieck, 1974 , which differs by having a higher spire, more convex whorls, and by forming a parietal tooth (“columellar tooth” in Mariottini et al. 2000) which R. nitida does not have. However, the specimens collected on GB have a low spire with slightly convex whorls and lack a parietal tooth, therefore being so similar to the lectotype of the American species ( Mariottini et al. 2000: fig. 7) that, except for the geographic distance, we see no reason for their specific separation with the material at hand. The only difference observed is the number of spiral striae, which are around 30 in GB shells, less conspicuous in the abapical part of the whorls, while they are about 14 in the lectotype of R. nitida . Bearing in mind that most of the other heterobranchs present in the area such as Acteon monterosatoi Dautzenberg, 1889 , Crenilabium exile (Jeffreys, 1870), Pyrunculus ovatus (Jeffreys, 1871) and Scaphander punctostriatus (Mighels & C.B. Adams, 1842) are considered amphiatlantic, we find more prudent to assign these specimens, tentatively, to R. nitida rather than describe them as a new species.

Figures

Fig. 29. Heterobranchia 2 (Cimidae,Acteonidae, Ringiculidae).A–B. Atomiscala islandica Warén, 1989, BANGAL 0711, DR15, 1410 m, 2.8 mm. C. Crenilabium exile (Jeffreys, 1870), BANGAL 0711, V10, 1720 m, 8.2 mm. D–E. Acteon monterosatoi Dautzenberg, 1889, SEAMOUNT 1, DW116, 985–1000 m, 2.5 mm. F–G. Ringicula nitida Verrill, 1872, BANGAL 0711, V2, 1706 m, 5.8 mm. H–I. Ringicula crassidens Gofas & Luque sp. nov., holotype (MNCN 15.05/200140H), BANGAL 0711, DR15, 2.2 mm high. J. Protoconch of a paratype (MNCN 15.05/200140P), same locality. K. Microsculpture of the second teleoconch whorl, same shell as J. Scale bars: A–I = 1 mm; J–K = 100 µm.