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 : 45

Gymnodoris sp. V

( Figs. 9I–J )

Material examined. New Caledonia: South Province: Nouméa, Ilôt Song ( 22°16.9'S, 166°28.8'E), 2 m depth, 30 Jan 2022, 1 specimen 5 mm preserved length [rocky coastal area] (MNHN-IM-2019-26479, isolate JD142), leg. Y. Thévenet. New Caledonia: South Province: Nouméa, Ilôt Song ( 22°16.91'S, 166°28.84'E), 1.5 m depth [Quinzaine des Nudibranches Expedition, stn. QNSR-FA, stones and algae], 8 Sep 2022, 1 specimen 4 mm preserved length (MNHN-IM-2019-26480, isolate JD90) .

Description. Body narrow, elongate, with several low, conical tubercles ( Figs. 9I–J ). Anterior end of notum with distinct velum having 8 small tubercles; notal rim absent, velum merges with notum behind rhinophores. Posterior end of foot tapering gradually into narrow, blunt “tail.” Color translucent white, tubercles opaque yellow; posterior end translucent. Internal organs and posterior branched glandular structures visible through body wall. Rhinophores conical, with 7 lamellae, with same color as body. Gill with 11–12 short, irregular, bipinnate leaves, translucent white, opaque white bases, arranged in circle around anus, opened posteriorly. Foot narrower than notum, translucent yellow. Oral tentacles small, blunt.

Phylogenetic position. Gymnodoris sp. V is sister to Gymnodoris sp. 17 (PP: 0.98, MLB: 70) and this clade is nested within a larger, well-supported clade (PP: 1, MLB: 94) also included Gymnodoris sp. U, Gymnodoris sp. 38, and Gymnodoris boiteuxi sp. nov. ( Fig. 1A ).

Remarks. This species was reported from New Caledonia by Hervé (2010) as Gymnodoris citrina (small photo) and it is clearly characterized by the large, conspicuous white glandular structure posterior to the gill. Gymnodoris sp. V is very similar in external morphology to Gymnodoris citrina , but the velum possesses very small tubercles instead of the elongate appendages of the latter.Also, the branchial leaves of G. citrina are much larger and tripinnate and form a complete circle around the anus. In Gymnodoris sp. V the leaves are small, bipinnate, and the circle is open posteriorly.

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 9. Gymnodoris sp. O, Gymnodoris sp. Q, Gymnodoris sp. V, Gymnodoris sp. X, and Gymnodoris sp. Y, photographs of live animals showing color variation. A. G. sp. O, specimen from Koumac, New Caledonia (MNHN-IM-2019-26495, isolate JD81). B. G. sp. O, specimen from Koumac, New Caledonia (MNHN-IM-2019-26494, isolate JD74). C. G. sp. O, specimen from Poum, New Caledonia (MNHN-IM-2019-26496, isolate JD112). D. G. sp. O, specimen from Poum, New Caledonia (MNHN-IM-2019-26499, isolate JD125). E. G. sp. O, specimen from Poum, New Caledonia (MNHN-IM-2019-26497, isolate JD115). F. G. sp. O, specimen from Poum, New Caledonia (MNHN-IM-2019-26498, isolate JD117). G. G. sp. O, specimen from Poum, New Caledonia (MNHN-IM-2019-26500, isolate JD139). H. G. sp. Q, specimen from Koumac, New Caledonia (MNHN-IM-2019-26521, isolate JD57). I. G. sp. V, specimen from Nouméa, New Caledonia (MNHN-IM-2019-26480, isolate JD90). J. G. sp. V, specimen from Nouméa, New Caledonia (MNHN-IM-2019-26479, isolate JD142), photo Y. Thévenet. K. G. sp. X, specimen from Poum, New Caledonia (MNHN-IM-2019-26423, isolate JD108). L. G. sp. Y, specimen from Koumac, New Caledonia (MNHN-IM-2019-26452, isolate JD80).