Alvinonemertes christianeae, Sagorny & Döhren & Rouse & Tilic, 2022

Sagorny, Christina, Döhren, Jörn von, Rouse, Greg W. & Tilic, Ekin, 2022, Cutting the ribbon: bathyal Nemertea from seeps along the Costa Rica margin, with descriptions of 2 new genera and 9 new species, European Journal of Taxonomy 845 (1), pp. 132-174 : 156-157

Alvinonemertes christianeae gen. et sp. nov.

urn:lsid:zoobank.org:act:B7C6217E-4889-4C9B-AEB8-B306A24FD93B

Fig. 8F

Diagnosis

Alvinonemertes christianeae gen. et sp. nov. can be attributed to the genus Alvinonemertes gen. nov. based on the strong support for a sister group relationship between the five species of this genus.

Etymology

For Christiane Wallnisch, lab technician at the Institute of Evolutionary Biology, University of Bonn. Acknowledging her support in the histology lab over many years. Christiane is a masterful histologist and has not only trained the first and the last author in histological sample preparation but has also sectioned most of the nemerteans included in this study.

Material examined

Holotype COSTA RICA • spec. (ethanol; entirely used up in DNA extraction; only image and DNA available); methane seep Jaco Scar ; 9.11507° N, 84.83978° W; depth 1887 m; 22 Oct. 2018; Shana Goffredi and Drew Bewley leg.; collected by HOV Alvin, Dive 4976; associated with experimentally deployed wood; SIO-BIC N253.

Paratype COSTA RICA • 1 spec. (ethanol; entirely used up in DNA extraction; only image and DNA available); non-seep seamount Quepos Plateau ; 8.58548° N, 84.54836° W; depth 2184 m; 26 Oct. 2018; Lisa Levin and Todd Litke leg.; collected by HOV Alvin, Dive 4980; associated with a naturally occurring wood fall; SIO-BIC N261 .

Description

Specimens 4–5 mm long and 0.5 mm in diameter. Body rounded. One pair of cephalic furrows. Head not demarcated from rest of body, rounded. Body coloration translucent white. Internal organs well visible through body wall ( Fig. 8F ).

Ecology

This species was collected on naturally occurring and experimentally deployed wood ( Pereira et al. 2022), including the same deployment associated with a paratype of the scaleworm Peinaleopolynoe elvisi Hatch & Rouse in Hatch, Liew, Hourdez & Rouse, 2020 (MZUCR 1000-01 ex SIO-BIC A9752).

Remarks

The new species is attributed to the genus Alvinonemertes gen. nov. based on the executed phylogenetic analysis. In the concatenated analysis, A. christianeae gen. et sp. nov. is sister to the newly described species A. claudiae gen. et sp. nov. from the North western Pacific. Together, both species are sister to A. tatjanae gen. et sp. nov. from the North western Pacific. This well-supported clade is firmly nested within the new genus Alvinonemertes ( Fig. 7 ).

Figures

Fig. 8. Live images of eumonostiliferous hoplonemerteans collected along the Costa Rica margin and the NE Pacific. A. Chernyshevia escarpiaphila sp. nov., paratype (SIO-BIC N112). B. Chernyshevia escarpiaphila sp. nov., paratype (SIO-BIC N266). C. Octocoral Paragorgia sp. (SIO-BIC Co3054) with several specimens of Alvinonemertes dariae sp. nov., holotype (arrows; ex SIO-BIC N262). D. Alvinonemertesdariaesp.nov.,holotype(exSIO-BICN262).E.Antipathariancoral(SIO-BICCo3031) with specimens of Alvinonemertes dagmarae sp. nov., holotype (SIO-BIC N260). F. Alvinonemertes christianeae sp. nov., holotype (SIO-BIC N253). G. Alvinonemertes claudiae sp. nov., holotype (ex SIO-BIC N231). H. Alvinonemertes tatjanae sp. nov., holotype (SIO-BIC N119). I. Eumonostilifera (SIO-BIC N259). J–L. Tetrastemma sundbergi sp. nov., holotype (SIO-BIC N256) whole animal (J), dorsal view of head (K), and ventral view of head (L). M. Tetrastemma polyakovae sp. nov. (MZUCR Nemertea Collection MZUCR-101-01).N. Tetrastemma polyakovae sp. nov., holotype (SIO-BIC N258), with everted proboscis. O. Eumonostilifera (SIO-BIC N109).

Fig. 7. Maximum likelihood (ML) tree for the monostiliferan supermatrix based on the concatenated four gene dataset (16S, COI, 18S, H3). Black circles indicate nodal support of 100/100/1.0; asterisks indicate nodal support of either 100/ or /1.0. Alternative branches found in the BI analysis are given as blue dotted lines. Sonnenemertes cantelli Chernyshev, Abukawa & Kajihara, 2015 and Micrura callima Sundberg & Gibson, 1995 were used for outgroup rooting. Specimens belonging to new species are given in bold. Specimen-ID, sampling locality, and depth (for deep-sea species) are provided.