Gymnodoris lebouteillerorum De Souza-Canal & Valdés, 2025

Gymnodoris lebouteillerorum De Souza-Canal & Valdés sp. nov.

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( Figs. 14G–H View FIGURE 14 , 15I View FIGURE 15 , 16A View FIGURE 16 )

Type material. Holotype: New Caledonia: North Province: Koumac, East of Karembé ( 20°39.6'S, 164°17.5'E), 2–5 m depth [Koumac 2.1 Expedition, stn. KR636, sandy bottom], 27 Sep 2018, 5 mm preserved length ( MNHN- IM-2019-26486 , isolate JD66). GoogleMaps

Description. Body narrow, elongate, with numerous, small conical tubercles mainly arranged around notal rim, a few on dorsum, velum; velum distinct with 16 tubercles ( Fig. 15I View FIGURE 15 ). Color translucent dirty-white, tubercles orange-red with blurry edges, faint orange-red line connecting velum, notal rim tubercles; faint longitudinal white line on posterior end of foot. Internal organs visible through body wall as orange, white masses. Rhinophores conical, with 6 lamellae, orange-red. Gill with 6 small, simple, translucent leaves with opaque white bases, arranged in row. Foot wider than notum, opaque white. Oral tentacles notched, anterior lobes.

Radular formula 8 × 9.0. 9 in the 5 mm preserved length holotype (MNHN-IM-2019-26389). Innermost lateral teeth small, hook-shaped, with straight, flat smooth cusps, broad bases ( Fig. 16A View FIGURE 16 ). Other lateral teeth elongate, with broad bases, long, slightly curved cusps ( Fig. 16A View FIGURE 16 ).

Reproductive system with an elongate, narrow, slightly curved ampulla, connecting to female gland complex, prostate ( Fig. 14G View FIGURE 14 ). Prostate large, tubular, curved around bursa copulatrix, narrowing into a highly convoluted deferent duct, opening into a common atrium with vagina. Vagina very long, convoluted, connecting into bursa copulatrix near seminal receptacle connection. Bursa copulatrix spherical, about twice as large as spherical seminal receptacle. Penial spines triangular to elongate (about 100–120 µm long), with relatively broad bases ( Fig. 14H View FIGURE 14 ).

Phylogenetic position. Gymnodoris lebouteillerorum sp. nov. is the most basal member of a supported clade (PP: 0.91, MLB: 84) also containing a monophyletic group (PP: 1, MLB: 99) including the species Gymnodoris sp. 24, Gymnodoris sp. 48, and Gymnodoris sp. 54, the last two being sister to one another (PP: 1, MLB: 100) ( Fig. 1A View FIGURE 1 ).

Etymology. This species is named in honor of Cathy and Aubert Le Bouteiller, indefatigable naturalists, who provided support during the “quinzaines” and collected numerous specimes.

Remarks. Gymnodoris lebouteillerorum sp. nov. is externally similar to Gymnodoris sp. 24, Gymnodoris sp. 48, and Gymnodoris sp. 54, also recovered in the same clade. However, all these species are genetically distinct. Externally, G. sp. 48, and G. sp. 54 are easily distinguishable by having a much denser pattern of very small orange dots on the dorsum, darker rhinophores, and branchial leaves with orange pigment (see Knutson & Gosliner 2022), all absent in G. lebouteillerorum sp. nov. Gymnodoris sp. 24 is also different as it has more orange tubercles on the dorsum and body sides and an orange dot at the posterior end of foot.