Skenea ponsonbyi, (Dautzenberg & H. Fischer, 1896)

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 : 48

“Skenea ” ponsonbyi (Dautzenberg & H. Fischer, 1896)

Fig. 15E‒F

Cyclostrema ponsonbyi Dautzenberg & H. Fischer, 1897: 176, pl. 4 figs 12–14.

Skenea ponsonbyi ‒ Hoffman et al. 2020c: 71–73.

Material examined

GALICIA BANK • 4 sh; 43°00.12′ N, 11°57.67′ W; 1706 m; 29 Jul. 2011; BANGAL 0711 V2; MNCN • 5 sh; 42°56.77′ N, 11°58.53′ W; 1631 m; 2 Aug. 2011; BANGAL 0711 V5; MNCN • 2 sh; 42°59.61′ N, 11°58.41′ W; 1671 m; 7 Aug. 2011; BANGAL 0711 V9; MNCN.

Remarks

This is, to our knowledge, the first time that this species is reported outside the Azores ( Dautzenberg & Fischer 1896) and the South Azorean Seamount Chain ( Hoffman et al. 2020c). The external sculpture recalls that of Moelleria costulata (Møller, 1842) , a boreal Atlantic species which belongs to the family Colloniidae Cossmann, 1917 and has a calcareous operculum fitting exactly the aperture; the flexuous contour of the aperture in the present species suggests that the operculum was flexible and that this similarity does not indicate reationship. For the time being, with no data on the living animal, there is no straightforward generic placement. Cyclostrema Marryat, 1819, a member of the family Liotiidae Gray, 1850 with also a calcareous operculum, is obviously inadequate and we conservatively use the catchall genus “ Skenea ”, in a broad sense meaning a skeneimorph species, following in that WoRMS Editorial Board (2021).

Figures

Fig. 15. Skeneimorph species 2. A–B. Akritogyra similis (Jeffreys, 1883), BANGAL 0711, V5, 1631 m, diameter 2.2 mm. C–D. Moelleriopsis sp., SEAMOUNT 1, DW108, 1120–1125 m, 2.7 mm. E–F. “Skenea” ponsonbyi (Dautzenberg & H. Fischer, 1896), BANGAL 0711, V9, 1671 m, 3.2 mm. G–H. Granigyrapruinosa (Jeffreys, 1883), BANGAL 0711,V10, 1720 m, 3.7 mm.I–J. SEM micrograph, same shell, and detail of microsculpture. K–L. Granigyra tenera (Jeffreys, 1883), BANGAL 0711, V10, 1720 m, 2.3 mm. Scale bars: A–I, K–L = 1 mm; J = 200 µm.