Ancistrobasis reticulata (Philippi, 1844)

Ortega, José Rafael & Gofas, Serge, 2019, The unknown bathyal of the Canaries: new species and new records of deep-sea Mollusca, Zoosystema 41 (26), pp. 513-551 : 522

Ancistrobasis reticulata (Philippi, 1844)

( Fig. 6 )

Solarium reticulatum Philippi, 1844: 149 ; pl. 25, fig. 6.

Ancistrobasis lavaleyei Hoffman & Freiwald, 2017: 63 , n. syn.

MATERIAL EXAMINED. — 24 sh., DW130,

REMARKS

New record for the Canaries. This species, originally described from Plio-Pleistocene strata in the valley of the Lamato river, in southernmost Calabria, Italy, has been reported in Recent NE Atlantic material by Warén & Bouchet (1990) from Galicia Bank, in 985- 100 m, and Warén (1991) from south of Iceland, in 970 m. It is actually quite well represented in our own material from Galicia Bank and from the Meteor and Atlantis seamounts, but the record here represents the southernmost known occurrence in the eastern Atlantic. The Western Atlantic A. costulata (Watson, 1879) described from off Culebra I., 390 fathoms, may be the same species but this has not been assessed.

Hoffman & Freiwald (2017) described Ancistrobasis lavaleyei based on a juvenile shell (1.43 × 1.89 mm) of A. reticulata collected on Coral Patch Seamount (34°58.00’N, 11°57.30’W, 1050 m) and included as a paratype an eroded shell from Galicia Bank. They mentioned that A. reticulata “is much larger, up to 10 mm; it has more than 10 spiral ribs that form a reticulated structure with nodes; and it lacks the angular outline on the first whorl.” Ancistrobasis reticulata does have an angular first whorl of teleoconch ( Fig. 6C herein and Warén 1991: fig. 1A) and the number of spirals gradually increases from one on the first whorl to about ten on specimens approaching full size about 10 mm. Based on the Canarian specimens and on additional material collected by the SEAMOUNT 2 expedition on the Meteor group of seamounts, we cannot see any grounds for distinguishing more than one species of recent Ancistrobasis in the North Atlantic, and treat A. lavaleyei as a synonym of A. reticulata .

Figures

FIG. 6. — A, B, Ancistrobasis reticulata (Philippi,1844),shell from DW130 (diam- eter 6.2 mm);C, protoconch of another shell, same locality. Scale bar:100 µm.