Strobiligera cf. georgiana ( Dall, 1927 )

Fernandes, Maurício Romulo, 2024, The deep-sea species of Triphoridae (Gastropoda, Triphoroidea) from Guadeloupe, sampled by the Karubenthos 2 expedition, European Journal of Taxonomy 972, pp. 1-52 : 33-34

Strobiligera cf. georgiana ( Dall, 1927)

Fig. 17A–B

Triphora (Biforina) georgiana Dall, 1927: 93 .

Triphora (Biforina) georgiana – Abbott 1974: 112.

“ Triphora ” georgiana – Rolán & Fernández-Garcés 2008: 140, fig. 24a–e.

Strobiligera georgiana – Fernandes & Pimenta 2014: 169, fig. 1a.

Type material

Lectotype

USA • sh; off Georgia; depth 805 m; USNM 333516.

Paralectotypes

USA • 5 sh; same data as for lectotype; USNM 1592888.

Material examined

GUADELOUPE (Karubenthos 2 expedition) • 1 sh; stn DW4550; MNHN.

Emended description

Shell sinistral, conical, up to 15.1 mm long (incomplete), 3.2 mm wide, apical angle of early whorls 20°. Protoconch multispiral, 3.75 whorls, 0.56 mm long, 0.44 mm wide; first whorl dome-shaped, with minute granules; subsequent whorls with two spiral cords, situated at 44% and 76% of whorl height; incomplete axial ribs (~27 ribs per whorl), with a smooth spiral zone above adapical spiral cord; abrupt transition to teleoconch. Teleoconch with 20 whorls (incomplete); two main spiral cords (median and abapical), with abapical one continuous with that of protoconch and median one emerging soon after; a very narrow adapical spiral cordlet more evident in late whorls, assuming a slightly nodulous appearance; shallow suture, almost indistinct, with a very narrow, smooth sutural cord; 14 slightly opisthocline axial ribs on 14 th whorl; moderately large, nearly rounded to slightly elliptical nodules. Base not formed. Protoconch light brown, teleoconch beige (initial whorls whitish).

Remarks

The single shell from Guadeloupe is possibly not S. georgiana (illustrated in Rolán & Fernández-Garcés 2008; Fernandes & Pimenta 2014), but the incomplete base in both morphs precluded further comparisons. Differences comprise the color of the teleoconch (beige in the shell from Guadeloupe, white in the type material) and the orientation of axial ribs (slightly opisthocline in the shell from Guadeloupe, but nearly orthocline in the type material).

Geographic distribution

USA: Georgia ( Dall 1927); Guadeloupe (this study).

Bathymetric distribution

Empty shells previously known from 805 m ( Dall 1927). This study: 432–482 m (empty shell).

Figures

Fig. 17. A–B. Strobiligera cf.georgiana (Dall, 1927), MNHN, stnDW4550, 15.1 mm. C–H. Strobiligera cf. delicata Fernandes & Pimenta, 2014. C. MNHN, stn DW4556, 8.9 mm. D. MNHN, stn DW4577, 8.9 mm. E–H. MNHN, stn DW4635, 7.0 mm. Scale bars: A, C–E = 1 mm; B, F–H = 500 µm.