Gymnodoris sp.

Gymnodoris sp. O

( Figs. 9A–G View FIGURE 9 )

Material examined. New Caledonia: North Province: Koumac, West coast of Récif de l’Infernet ( 20°36.1'S, 164°13.4'E), 0 m depth [Koumac 2.1 Expedition, stn. KR208, reef flat with living and dead corals, seagrass patches], 25 Sep 2018, 1 specimen 3 mm preserved length (MNHN-IM-2019-26495, isolate JD81) GoogleMaps . New Caledonia: North Province: Koumac, Pointe Pandop ( 20°34.9'S, 164°16.6'E), 0 m depth [Koumac 2.2 Expedition, stn. KM100 , rocky shore, rubble, sand, mud, seagrasses], 28 Feb 2019, 1 specimen 19 mm preserved length (MNHN-IM-2019-26494, isolate JD74) GoogleMaps . New Caledonia: North Province: Poum, Ilôt St. Phalles ( 20°6.7'S, 164°6.57'E), 0 m depth [ABC Poum Expedition, stn. ABC03 , slopes of the island], 11 Jun 2023, 1 specimen 4 mm preserved length (MNHN-IM-2019-26496, isolate JD112) GoogleMaps . New Caledonia: North Province: Poum, Ilôt Boh ( 20°19.82'S, 164°5.55'E), 0 m depth [ABC Poum Expedition, stn. ABC09 , intertidal], 12 Jun 2023, 1 specimen 6 mm preserved length (MNHN-IM-2019-26499, isolate JD125) GoogleMaps . New Caledonia: North Province: Poum, Ilôt St. Phalles ( 20°6.75'S, 164°6.63'E), 0 m depth [ABC Poum Expedition, stn. ABC15 , slopes of the island], 12 Jun 2023, 1 specimen 4 mm preserved length (MNHN-IM-2019-26497, isolate JD115) GoogleMaps . New Caledonia: North Province: Poum, Ilôt Cocotier ( 20°12.25'S, 164°13.16'E), 0 m depth [ABC Poum Expedition, stn. ABC36 , slopes of the island], 16 Jun 2023, 1 specimen 4 mm preserved length (MNHN-IM-2019-26498, isolate JD117) GoogleMaps . New Caledonia: North Province: Poum, East Ilôt Baaba ( 20°2.92'S, 163°59.87'E), 0 m depth [ABC Poum Expedition, stn. ABC47 , intertidal], 18 Jun 2023, 1 specimen 7 mm preserved length (MNHN-IM-2019-26500, isolate JD139) GoogleMaps .

Description. Body oval to elongate, with several low, conical tubercles ( Figs. 9A–G View FIGURE 9 ). Velum differentiated, smooth narrowing anteriorly into keel. Notal rim absent, velum merges with notum behind rhinophores. Posterior end of foot broad, tapering abruptly into short, narrow “tail.” Color translucent yellow, tubercles opaque yellow. Internal organs and posterior branched glandular structures visible through body wall. Rhinophores conical, with 6– 7 lamellae, with same color as body. Gill with 12–14 narrow, irregular, bipinnate leaves, translucent yellow, opaque white bases, arranged in circle around anus. Foot narrower than notum, except at posterior end, translucent yellow.

Phylogenetic position. Gymnodoris sp. O is sister to Gymnodoris sp. P (PP: 1, MLB: 96) but the position of this clade within the broader phylogeny of Gymnodoris is poorly supported ( Fig. 1A View FIGURE 1 ).

Remarks. This is a common species in New Caledonia previously reported from the Marshall Islands by Knutson & Gosliner (2022) and possibly from Japan by Nakano (2018) as Gymnodoris sp. 19.