Gymnodoris impudica (Rüppell & Leuckart, 1830)

Gymnodoris impudica (Rüppell & Leuckart, 1830) View in CoL

( Figs. 2A–L View FIGURE 2 )

Doris impudica Rüppell & Leuckart, 1830: 33–34 , pl. 10, figs. 2A–C. Type locality: El Tor, Egypt.

Trevelyana rubropapulosa Bergh, 1905: 191–192 View in CoL , pl 4, fig. 15, pl. 17, figs. 27–31, pl. 18, figs. 1–3. Type locality: Near “Saleyer” [= Selayar Island, Indonesia].

Material examined. New Caledonia: North Province: Koumac, Koumac Bay ( 20°34.2'S, 164°16.5'E), 0 m depth [Koumac 2.1 Expedition, stn. KM 101], 7 Sep 2018, 1 specimen 23 mm preserved length (MNHN-IM-2019-26355, isolate JD18). New Caledonia: North Province: Koumac, Exterior NW Infernet Reef ( 20°35.5'S, 164°12.9'E), 10 m depth [Koumac 2.1 Expedition, stn. KR619, sandy-muddy, algal patches], 19 Sep 2018, 1 specimen 28 mm preserved length (MNHN-IM-2019-26427, not sequenced). New Caledonia: North Province: Koumac, Pandop Point marker (South rock) ( 20°35.5'S, 164°16.3'E), 6 m depth [Koumac 2.1 Expedition, stn. KR624, sandy-muddy bottom with some algae ( Caulerpa , Halimeda ) and sponge aggregates], 23 Sep 2018, 1 specimen 11 mm preserved length (MNHN-IM-2019-26356, isolate JD15). New Caledonia: North Province: Koumac, East of Karembé ( 20°39.1'S, 164°17.6'E), 6 m depth [Koumac 2.1 Expedition, stn. KR633, species rich sand], 26 Sep 2018, 1 specimen 31 mm preserved length (MNHN-IM-2019-26358, isolate JD02). New Caledonia: North Province: Koumac, Reef facing Pandop Point ( 20°35.3'S, 164°16.4'E), 7 m depth [Koumac 2.1 Expedition, stn. KR869, rocky reef sloping down to 7 m depth, with algae and sponges], 27 Sep 2018, 1 specimen 22 mm preserved length (MNHN-IM-2019-26359, isolate JD11). New Caledonia: North Province: Koumac, Baron Pass (white bottoms) ( 20°33.8'S, 164°10.3'E), 0 m depth [Koumac 2.1 Expedition, stn. KR 644], 29 Sep 2018, 1 specimen 18 mm preserved length (MNHN-IM-2019-26357, isolate JD92). New Caledonia: North Province: Koumac ( 20°33.1'S, 164°13.9'E), 6 m depth [Koumac 2.3 Expedition, stn. KR 902], 1 Nov 2019, 1 specimen 20 mm preserved length (MNHN-IM-2019- 26361, isolate JD93). New Caledonia: North Province: Koumac ( 20°33.7'S, 164°13.1'E), 12 m depth [Koumac 2.3 Expedition, stn. KR 875], 3 Nov 2019, 1 specimen 21 mm preserved length (MNHN-IM-2019-26362, isolate JD95). New Caledonia: North Province: Koumac ( 20°35.5'S, 164°16.4'E), 8 m depth [Koumac 2.3 Expedition, stn. KR 882], 7 Nov 2019, 1 specimen 22 mm preserved length (MNHN-IM-2019-26364, isolate JD14). New Caledonia: North Province: Koumac ( 20°40.2'S, 164°16.6'E), 7 m depth [Koumac 2.3 Expedition, stn. KD 549], 10 Nov 2019, 1 specimen 24 mm preserved length (MNHN-IM-2019-26363, isolate JD09). New Caledonia: North Province: Koumac ( 20°34.4'S, 164°13.8'E), 8 m depth [Koumac 2.3 Expedition, stn. KR 918], 20 Nov 2019, 1 specimen 24 mm preserved length (MNHN-IM-2019-26360, isolate JD94). New Caledonia: North Province: Koumac ( 20°35.3'S, 164°16.4'E), 6 m depth [Koumac 2.3 Expedition, stn. KR 885], 21 Nov 2019, 1 specimen 28 mm preserved length (MNHN-IM-2019-26426, isolate JD01).

Description. Body elongated, narrow, covered with numerous large, rounded to conical tubercles. Velum distinct with 7–9 irregular tubercles on edge; notal rim not differentiated, velum merges with dorsum behind rhinophores ( Figs. 2A–L View FIGURE 2 ). Posterior end of foot tapering slightly into robust “tail.” Color opaque white, tubercles yellow to orange, smaller orange spots between tubercles. Internal organs not visible, except for faint dark mass anterior to gill. Rhinophores bulbous, with 10–14 lamellae, dark orange to red. Gill with 8–12 large, broad, tripinnate leaves, lamellae white, rachises orange. Foot wider than notum, surrounded by orange line, small yellow, elongate glandular structures, orange spots on sides; oral tentacles small, blunt, red.

Phylogenetic position. Gymnodoris impudica appears to be sister to Gymnodoris inornata ( Bergh, 1880) , but this relationship is poorly supported in the ML analysis (PP: 0.99, MLB: 67) of the concatenated dataset ( Fig. 1A View FIGURE 1 ).

Remarks. Rüppell & Leuckart (1830) originally described Doris impudica from the Egyptian Red Sea as having a tuberculated dorsum, milky in color, with orange spots, rhinophores, branchial leaves, and edge of the foot are orange. This description matches the characteristics of the material here examined as well as illustrations in recent literature as G. impudica (e.g., Yonow, 2008; Nakano, 2018) including records from Nouméa, New Caledonia ( Hervé, 2010). Moreover, all the specimens from New Caledonia cluster are in the same clade and are recovered as the same species as specimens from Vanuatu and Singapore identified as G. impudica .

Trevelyana rubropapulosa originally described by Bergh (1905) from Indonesia has been regarded as a synonym of G. impudica ( Yonow, 2008, 2011; Nakano, 2018) but treated as a distinct species by other authors (e.g., Rudman & Darvell, 1990; Martynov & Korshunova, 2012; Gosliner et al., 2018) in the binomen Gymnodoris rubropapulosa . To date, no specimens from the Indian Ocean or the Red Sea have been sequenced to verify whether the specimens from the Western Pacific belong to the same species. Thus, the correct name for the material here examined remains unclear, until sequence data from the Indian Ocean become available. To be consistent with previous records from New Caledonia, and in absence of evidence that G. rubropapulosa is distinct, we will hesitantly use the older available name G. impudica for the material here examined.