Conus (Kurodaconus) darkini, Tenorio & Puillandre, 2023

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 : 82

Conus (Kurodaconus) darkini R̂ckel, Korn & Richard, 1993

Figs 2 , 61A–C, I , 62

Conus darkini R̂ckel et al., 1993: 48, figs 1–4.

Conus darkini – R̂ckel et al. 1995b: no. 119, pl. 27 figs 22–25.

Embrikena darkini – Tucker & Tenorio 2013: 161.

Turriconus (Kurodaconus) darkini – Monnier et al. 2018a: 347.

Material examined

4 lots (4 specimens). See Supp. file 1.

Type material

Holotype NEW CALEDONIA • 55.7 mm; Loyalty Ridge, LIFOU, E Cap de Pins , off New Caledonia, stn CP467; 21º06′ S, 167º32′ E; 530‒575 m depth; 21 Feb. 1989; MUSORSTOM 6 expedition; MNHNIM- 2000-2568 ( Fig. 61A ).

Figured material

NEW CALEDONIA • 57.3 mm; Récif Pétrie , off New Caledonia, stn DW3930; 18°37′ S, 164°26′ E; 448‒464 m depth; 26 Sep. 2011; EXBODI expedition; MNHN ( Fig. 61B, I ) • 78 mm; Norfolk Ridge , Banc Munida, off New Caledonia, stn CP2143; 23º01′ S, 168º17′ E; 564‒590 m depth; 3 Nov. 2003; NORFOLK 2 expedition; MNHN ( Fig. 61C ) .

Geographical distribution and bathymetry

New Caledonia: Loyalty Ridge and Norfolk Ridge, at depths between 400 and 600 m. Also reported from the Philippines (Balut Island) and the Kita-Koho area (Philippine Sea), at depths between 285– 325 m. One specimen known from French Polynesia, dredged between 300 and 600 m off Moorea.

Remarks

Shell moderately large to large (maximum shell length 87 mm), ventricosely conical to conical, with a high or moderate stepped spire of straight or slightly concave profile. Larval shell multispiral of about 3.5 whorls. Radular tooth ( Fig. 61I ) with the anterior section much shorter than the posterior section. The tooth is serrated with 15–18 minute denticles arranged in two or three rows. Small rounded terminating cusp present. Barb well marked. Blade rounded, indistinct, covering most of the anterior section of the tooth. Strong basal spur on top of the rounded base. Prior to radular examination, this species was considered a member of Profundiconus (Tenorio & Castelin 2016) . Upon radular examination, it was tentatively placed in the genus Embrikena (Tucker & Tenorio 2013) . DNA studies clearly indicate that C. darkini belongs to the same clade as Conus (Kurodaconus) stupa Kuroda, 1956 , which is its sister species in the phylogeny ( Fig. 2 ), and the type species for the genus Kurodaconus . Conus (K.) darkini is an elusive species, and very few specimens have been sampled.

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. 61. A–C. Conus (Kurodaconus) darkiniR̂ckel, Korn & Richard, 1993. A. Holotype, Loyalty Ridge, 530‒575 m depth, 55.6 mm (MNHN-IM-2000-2568). B. Récif Pétrie, off New Caledonia, 448‒464 m depth, 57.3 mm. C. Banc Munida, Norfolk Ridge, 564‒590 m depth, 78 mm. – D. Conus (Kurodaconus) stupella Kuroda, 1956. Grand Passage, 277‒289 m depth, 40.5 mm. – E–H. Conus (Kurodaconus) stupa (Kuroda, 1956). E. Banc Munida, Norfolk Ridge, 372‒393 m depth, 81.1 mm. F. Banc Munida, Norfolk Ridge, 547‒560 m depth, 81.3 mm. G. Loyalty Ridge, 430 m depth, 73.3 mm. H. Banc Munida, Norfolk Ridge, 402‒410 m depth, 36.5 mm. – I. C. (K.) darkini. Radular tooth of specimen B. – J. C. (K.) stupa. Radular tooth of specimen G. – K. C. (K.) stupella. Radular tooth of a specimen from Taiwan, 68.7 mm (MJT coll.). Scale bars = 10 mm, unless otherwise stated.

Fig. 62. Bathymetric range and distribution map for Conus (Kurodaconus) darkini R̂ckel, Korn & Richard, 1993. Red circles indicate the points where the species was collected.