Strobiligera carioca, Fernandes, 2024

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 : 41-42

Strobiligera carioca sp. nov.

urn:lsid:zoobank.org:act:3D4D214A-711A-4BB0-B16B-53C60CF95B68

Fig. 21

non Triphora compsa Dall, 1927 – Absalão 1989: 3.

non Inella apexbilirata Rolán & Fernández-Garcés, 2008 – Fernandes & Pimenta 2019a: 9 , fig. 4.

Diagnosis

Light brown/beige shell; protoconch with a small nucleus; adapical spiral cord of teleoconch reaching same size as other spiral cords between eighth and twelfth whorl.

Etymology

The specific epithet alludes to the citizens of Rio de Janeiro, referring to the restricted geographic range of the species to this state. Epithet as a noun in apposition.

Type material

Holotype

BRAZIL • sh; Rio de Janeiro State, Campos Basin ; 22°48ʹ S, 40°45ʹ W; depth 106–110 m; 27 Jan. 1998; MNRJ 36601 .

Paratypes

BRAZIL • 3 sh; same data as for holotype; IBUFRJ 23518 .

Additional material examined

See Fernandes & Pimenta (2019a) for the species previously determined as I. apexbilirata . The holotype and paratypes were removed from IBUFRJ 19577, which remains as ordinary material.

Description

See Fernandes & Pimenta (2019a) for the species previously determined as I. apexbilirata .

Remarks

As addressed by Fernandes & Pimenta (2019a), most adult shells of this species are larger than shells of I. apexbilirata , described from the Bahamas, although there are small adults of S. carioca sp. nov., reaching 4.2 mm in length ( Fernandes & Pimenta 2019a: fig. 4e) vs 3.5 mm in I. apexbilirata . The authors argued that their main differences are related to shell color and bathymetric range ( S. carioca : mid-end of continental shelf; I. apexbilirata : bathyal). In addition, the abapical spiral cord is slightly more developed in the Bahamian species ( Rolán & Fernández-Garcés 2008), whereas the median cord is more developed than other cords on the initial whorls of the teleoconch in S. carioca . The adapical spiral cord of the teleoconch reaches nearly the same size as other cords between the eighth and twelfth whorls in S. carioca , but it is much less developed until the eighth whorl in I. apexbilirata . Considering all these differences and their non-planktotrophic development, these species probably have restricted geographic ranges, and neither of them was sampled from Guadeloupe by the Karubenthos 2 expedition.

All material of S. carioca sp. nov. listed by Fernandes & Pimenta (2019a – as I. apexbilirata ) and stored in IBUFRJ is available, whereas that from MNRJ and MORG (Museu Oceanográfico “Prof. Eliézer de Carvalho Rios”, Rio Grande, Brazil) was lost during the 2018 fire in MNRJ. The single shell listed from Espírito Santo State (IBUFRJ 19619) was indicated as a very worn juvenile and therefore this record needed confirmation ( Fernandes & Pimenta 2019a). Yet, after a new evaluation, this shell cannot be confidently assigned to this species. Thus, this species is currently known only from Rio de Janeiro State.

Geographic distribution

Brazil: Rio de Janeiro State.

Bathymetric distribution

Empty shells from 69 to 163 m ( Fernandes & Pimenta 2019a).

Figures

Fig. 21. Strobiligera carioca sp. nov. A, D–E. Holotype, MNRJ 36601, 11.1 mm. B–C. Paratypes, IBUFRJ 23518, 8.1 mm, 8.6 mm. Scale bars: A–C, E = 1 mm; D = 500 µm.