Conus (Klemaeconus) plinthis Richard & Moolenbeek, 1988

Tenorio, Manuel J. & Puillandre, Nicolas, 2023, Revision of the deep-water cone snail fauna from New Caledonia (Gastropoda, Conoidea), European Journal of Taxonomy 896, pp. 1-134 : 77-79

Conus (Klemaeconus) plinthis Richard & Moolenbeek, 1988

Figs 2 , 57–58

Conus plinthis Richard & Moolenbeek, 1988: 235 , pl. 1 figs 6–9, 11.

Conus plinthis – R̂ckel et al. 1995b: no. 216, pl. 48 figs 19–22.

Continuconus plinthis – Tucker & Tenorio 2013: 323. — Monnier et al. 2018a: 325.

Material examined

150 lots (368 specimens). See Supp. file 1.

Type material

Holotype NEW CALEDONIA • 43.9 mm; S of Grande-Terre, off New Caledonia , stn DW210; 22º43′ S, 167º09′ E; 340–345 m depth; 28 Sep. 1985; MUSORSTOM 4 expedition; MNHN-IM-2000-2526 ( Fig. 57A ).

Figured material

NEW CALEDONIA • 31.2 mm; off S New Caledonia, stn DW9; 24º42′ S, 168º08′ E; 265 m depth; 21 May 1987; SMIB 3 expedition; MNHN ( Fig. 57B ) • 38.3 mm; Norfolk Ridge, off New Caledonia, stn DW163; 24º50′ S, 168º09′ E; 310–460 m depth; 28 Jan. 1993; SMIB 8 expedition; MNHN ( Fig. 57C ) • 30.4 mm; Norfolk Ridge, off New Caledonia, stn DW187; 23º17′ S, 168º06′ E; 390‒540 m depth; 31 Jan. 1993; SMIB 8 expedition; MNHN ( Fig. 57D ) • 36.7 mm; Norfolk Ridge, off New Caledonia, stn CP162; 24º48′ S, 168º09′ E; 254‒264 m depth; 28 Jan. 1993; SMIB 8 expedition; MNHN ( Fig. 57E ) • 41 mm; off S New Caledonia, Banc Kaimon Maru, stn DW43; 24º46′ S, 168º09′ E; 235‒245 m depth; 8 Mar. 1989; SMIB 4 expedition; MNHN ( Fig. 57F ) • 26.3 mm; off New Caledonia, stn DW184; 19º04′ S, 163º 27º E; 260 m depth; 18 Sep. 1985; MUSORSTOM 4 expedition; MNHN ( Fig. 57G ) • 32 mm; Norfolk Ridge, off New Caledonia, stn DW159; 23º46′ S, 168º08′ E; 241–245 m depth; 28 Jan. 1993; SMIB 8 expedition; MNHN ( Fig. 57H ) • 29.1 mm; same collection data as for preceding; MNHN ( Fig. 57I ) • 26 mm; Banc Antigonia, off New Caledonia, stn DW183; 23º17′ S, 168º05′ E; 330–367 m depth; 31 Jan. 1993; SMIB 8 expedition; MNHN ( Fig. 57J ) • 20 mm; Norfolk Ridge, Jumeau Ouest, off New Caledonia, stn DW3056; 23°42′ S, 168°01′ E; 250–330 m depth; 20 Oct. 2008; TERRASSES expedition; MNHN ( Fig. 57K ) • size unknown; Norfolk Ridge, Banc Kaimon Maru, off New Caledonia, stn DW1679; 24º43′ S, 168º10′ E; 298‒324 m depth; 22 Jun. 2001; NORFOLK 1 expedition; MNHN ( Fig. 57L ) • 29.7 mm; Norfolk Ridge, off New Caledonia, stn DW187; 23°17′ S, 168°06′ E; 390– 540 m depth; 31 Jan. 1993; SMIB 8 expedition ( Fig. 57M ).

Geographical distribution and bathymetry

New Zealand (Kermadec Islands, N Three Kings Rise) at depths between 135 and 844 m, Australia ( Norfolk Island) and New Caledonia, mainly in Norfolk Ridge, but also in Grand Passage, Loyalty Islands, New Hebrides Arc ( Vanuatu, Hunter Island) and Coral Sea (Nova, Capel and Landsdowne Banks), at depths between 200‒ 500 m. Also present in Fiji at depths between 262‒266 m ( Moolenbeek et al. 2008). Specimens of this species have also been collected in 227‒367 m on a seamount off the Tonga Islands during MNHN expedition BORDAU 2.

Remarks

Conical shell, moderately small to medium-sized (maximum shell length 65 mm) with a low to moderate spire of concave outline. Protoconch multispiral of about 3.25 whorls ( Fig. 57L ). Radular tooth ( Fig. 57M ) elongated with the anterior section slightly narrower and longer than the posterior section. Barb short. Blade rounded, covering about one-third of the anterior section. There is a pronounced row of serrations that runs the entire length of the anterior section of the tooth, ending at the terminating cusp. Basal spur present. This is one of the most representative species of the New Caledonia deep water cone fauna, and relatively common among the samples studied. However, it can not be considered endemic, as it is also present at other locations outside of the New Caledonia EEZ. In the phylogeny ( Fig. 2 ) it is sister to Conus (Klemaeconus) whiteheadae da Motta, 1985 .

Figures

Fig. 2. Cox1-based Bayesian phylogeny. Posterior probabilities (> 0.95) and bootstrap values (> 90) from the ML analysis are provided for each node. Intraspecific relationships are collapsed. Subgenus names are indicated on the right.

Fig. 57. Conus (Klemaeconus) plinthis Richard & Moolenbeek, 1988. A. Holotype, S New Caledonia, 340‒345 m depth, 43.9 mm (MNHN-IM-2000-2526). B. Banc Kaimon Maru, Norfolk Ridge, 265 m depth, 31.2 mm. C. Norfolk Ridge, 310–460 m depth, 38.3 mm. D. Norfolk Ridge, 390‒540 m depth, 30.4 mm. E. Norfolk Ridge, 254‒264 m depth, 36.7 mm. F. Banc Kaimon Maru, Norfolk Ridge, 235‒245 m depth, 41 mm. G. Off New Caledonia, 260 m depth, 26.3 mm. H. Norfolk Ridge, 241– 245 m depth, 32 mm. I. Same collection data as for specimen H, 29.1 mm. J. Banc Antigonia, Norfolk Ridge, 330–367 m depth, 26 mm. K. Banc Jumeau Ouest, Norfolk Ridge, 250–330 m depth, 20 mm. L. Protoconch of specimen from Banc Kaimon Maru, Norfolk Ridge, 298‒324 m depth. M. Radular tooth of specimen from Norfolk Ridge, 390‒540 m depth, 29.7 mm. Scale bars = 10 mm, unless otherwise stated.

Fig. 58. Bathymetric range and distribution map for Conus (Klemaeconus) plinthis Richard & Moolenbeek, 1988. Red circles indicate the points where the species was collected.