Rissoidae (Mollusca: Gastropoda) from northeast Atlantic seamounts
Author
Gofas, Serge
text
Journal of Natural History
2007
2007-06-04
41
13 - 16
779
885
http://dx.doi.org/10.1080/00222930701298085
journal article
10.1080/00222930701298085
1464-5262
5229647
Benthonellania fayalensis
(
Watson, 1886
)
(
Figure 56
)
Rissoa fayalensis
Watson 1886
, p 589
, Plate 44
Figure 7
.
Type material
Holotype
(sh., 1.60×
0.93 mm
) from Challenger sta. 75, in
BMNH
(1897.2.9.1896).
Type locality
Off Fayal
,
Azores
(38
°
389N,
28
°
28.59W
,
819–910 m
)
.
Material examined
Ampère—
Victor Hensen
VH
97 sta. 97, 5 sh. (1.44×1.00 to 1.90×
1.14 mm
); sta. 104, 2 sh. (1.48×0.94 to 1.70×
1.04 mm
).
Figure 56.
Benthonellania fayalensis
(
Watson, 1886
)
. (A) Shell from Ampère bank,
Victor Hensen
sta. VH97/97 (800 m), actual size 1.90 mm; (B) protoconch of another shell, same locality; (C) detail of microsculpture, same as (A). Scale bars: 100 Mm (B); 50 Mm (C).
Remarks
The specimens collected on Ampère seamount agree well with the specimens from the
type
locality and nearby (see
Bouchet and Warén 1993
, p 680–681), so that this is the first unambiguous report of the species outside the Azores. The reservations expressed previously regarding the assignment to
Benthonellania
also apply here but, in the absence of data on the living animal the generic placement by
Bouchet and Warén (1993)
will be respected. The specimens from Ampère seamount and those from the
Monaco
station cited in Bouchet and Warén were examined under SEM for microsculpture. The former do not show a
Porosalvania
microsculpture, only very tenuous spiral lines of slit-like pores on some parts of the shells (
Figure 56C
), and the latter are too corroded by acidic glass to conserve any kind of microsculpture.