Gymnodoris sp.

Souza-Canal, Jade De & Valdés, Ángel, 2025, The genus Gymnodoris Stimpson, 1855 (Mollusca, Nudibranchia) in New Caledonia, with descriptions of eleven new species, Zootaxa 5710 (1), pp. 1-73 : 53-54

Gymnodoris sp. 53

( Fig. 12H )

Material examined. New Caledonia: North Province: Koumac, Barrière Piscine ( 20°34.7'S, 164°06'E) [Koumac 2.1 Expedition, stn. KR217, interior of the pool], 16 Sep 2018, 1 specimen 3 mm preserved length (MNHN-IM-2019-26414, isolate JD79) .

Description. Single specimen damaged. Body shape unknown, with low, conical tubercles, mainly arranged along the notal rim ( Fig. 12H ). Velum merged with notal rim, with irregular extensions/tubercles. Color translucent white, tubercles, velum edge, anterior, posterior ends of foot red. Rhinophores bulbous, with 11 lamellae, red. Gill unknown. Oral tentacles small, blunt.

Phylogenetic position. Gymnodoris sp. 53 is sister to Gymnodoris sp. A (PP: 1, MLB: 99) and this clade is sister to Gymnodoris sp. 14 (PP: 0.96, MLB: 78), but the position of these three species in the larger phylogeny of Gymnodoris is unsupported ( Fig. 1A ).

Remarks. The specimen here examined was heavily deformed during collection, but it could be positively identified as Gymnodoris sp. 53 sensu Gosliner et al. (2018) and Knutson & Gosliner (2022) using molecular data. This species is rare in New Caledonia, it was reported from Nouméa by Hervé (2010) as Gymnodoris sp. 2 (large photo) and Koumac (present study).

New species. In this section new species to science are described. These species are based on material collected in New Caledonia and could not be matched with specimens studied by Knutson & Gosliner (2022).

Figures

FIGURE 1. A. Bayesian consensus phylogenetic tree of the concatenated dataset including PP above branches and MLB below branches. Branches fully supported (PP: 1, MLB: 100) marked with asterisks. New species described in this paper highlighted in red font and illustrated; other species reported from New Caledonia in this study highlighted in blue font. Clades are collapsed according to the results of the ASAP and bPTP species delimitation analyses. B. Histogram representing the distance plot from the ASAP analysis using the COI gene showing pairwise p-distances (Kimura 2 model) among candidate species. The dashed line represents the distance threshold provided by the lowest ASAP score for species delimitation.

FIGURE 12. Gymnodoris sp. 15, Gymnodoris sp. 16, Gymnodoris sp. 34, Gymnodoris sp. 51, and Gymnodoris knutsonae sp. nov., photographs of live animals showing color variation. A. G. sp. 15, specimen from Nouméa, New Caledonia (MNHN-IM- 2019-26462, isolate JD86). B. G. sp. 16, specimen from Koumac, New Caledonia (MNHN-IM-2019-26430, isolate JD45). C. G. sp. 16, specimen from Koumac, New Caledonia (MNHN-IM-2019-26429, isolate JD34). D. G. sp. 34, specimen from Koumac, New Caledonia (MNHN-IM-2019-26453, isolate JD163). E. G. sp. 34, specimen from Nouméa, New Caledonia (MNHN-IM- 2019-26454, isolate JD145), photo Y. Thévenet. F. G. sp. 34, specimen from New Caledonia: Loyalty Is.: Ouvéa, (MNHN-IM- 2019-26517, isolate JD184). G. G. sp. 51, specimen from Nouméa, New Caledonia (MNHN-IM-2019-26481, isolate JD73). H. G. sp. 53, specimen from Nouméa, New Caledonia (MNHN-IM-2019-26414, isolate JD79). I. G. knutsonae sp. nov., paratype, Koumac, New Caledonia (MNHN-IM-2019-26382, isolate JD64). J. G. knutsonae sp. nov., paratype Koumac, New Caledonia (MNHN-IM-2019-26380, isolate JD53). K. G. knutsonae sp. nov., holotype, Koumac, New Caledonia (MNHN-IM-2019- 26381, isolate JD60).