Leucosyrinx undosa ( Schepman, 1913 ), 2025

Kantor, Yuri I., Fedosov, Alexander & Puillandre, Nicolas, 2025, Revision of the Indo-Pacific species of the genus Leucosyrinx Dall, 1889 (Neogastropoda: Conoidea: Pseudomelatomidae), European Journal of Taxonomy 999, pp. 1-126 : 102-105

Leucosyrinx undosa ( Schepman, 1913) comb. nov.

Fig. 33E

Surcula undosa Schepman, 1913: 61 (425), pl. 27 fig. 13a–b.

Comitas undosa – Powell 1969: 282 (23-294), pl. 227 figs 3–4.

Paracomitas undosa – Shuto 1970a: 170, pl. 11 figs 8–9.

Type material

Holotype

INDONESIA • Flores Sea ; 7°24′ S, 118°15.2′ E; depth 794 m; NATURALIS, ZMA.MOLL.136841.

Remarks

In general shell characters, including the position of the anal sinus, the species is referable to Leucosyrinx . Shuto (1970a) transferred it to Paracomitas Powell, 1942 . In our opinion this is unjustified. The genus Paracomitas is characterized and differentiated from Leucosyrinx and Comitas by a protoconch of 2.5 sharply carinated whorls. The protoconch is missing in the holotype of S. undosa , the only known specimen of the species. Therefore, pending additional data, we consider it a species of Leucosyrinx .

Distribution

Type locality.

Doubtful species, attributed herein to Leucosyrinx

The following species are conditionally attributed to Leucosyrinx pending further anatomical data and the collection of additional material. We are taking a conservative approach and will retain the species’ current generic position unless there are significant reasons to transfer them.

“ Leucosyrinx ” caecilia Thiele, 1925

Fig. 34A

Leucosyrinx caecilia Thiele, 1925: 202 (236), pl. 24 (36) fig. 23.

Leucosyrinx caecilia – Powell 1969: 337 (23-401), pl. 257 fig. 2.

Type material

Holotype

TANZANIA • Dar-es-Salaam: 6°34′ S, 39°35′ E; depth 404 m; ZMB Mol 109385.

Remarks

The single known specimen is the juvenile holotype, with SL of 7.5 mm. The anal sinus is typical of Leucosyrinx , but the shoulder is accentuated by two distinct and broad spiral cords that appear wavy on poorly pronounced axial folds. This type of sculpture is not found in other species of the genus, but it is unclear whether these features are characteristics of the juvenile shell or of the species as a whole. We tentatively retain the species within Leucosyrinx , though with some reservations.

Distribution

Type locality.

“ Leucosyrinx ” canyonensis ( Dell, 1956)

Fig. 34B

Antimelatoma canyonensis Dell, 1956: 142 , fig. 196.

Leucosyrinx canyonensis – Powell 1979: 230, fig. 53: 3. — Spencer et al. 2011.

Type material

Holotype

NEW ZEALAND • South I., off east Otago; depth 260–350 ftm (= 475–640 m); MNZ, M.009262.

Remarks

The species is characterized by a small shell (SL 9.3 mm in the holotype) with strong spiral cords and a distinct crenulated shoulder carina. It is rather different from known species of Leucosyrinx , but in the absence of any data on anatomy, we retain it in Leucosyrinx with strong doubts.

Distribution

Type locality.

“ Leucosyrinx ” erna Thiele, 1925

Fig. 34C

Leucosyrinx erna Thiele, 1925: 201 (235), pl. 24 (36) fig. 22.

Leucosyrinx erna – Powell 1969: 337 (23-401), pl. 257 fig. 1.

Type material

Syntypes

TANZANIA • 3 specs; Zanzibar Channel ; 5°27′ S, 39°19′ E; depth 463 m; ZMB Mol 109384 .

Remarks

The species is known from three dead-collected and immature shells (maximal SL 7.8 mm). It is characterized by strong and very closely spaced spiral cords below shoulder that was not found in other species of Leucosyrinx , although somewhat similar but broader cords are also found in L. nodulocordata sp. nov. In the absence of any data on anatomy, we retain it in Leucosyrinx with strong doubts.

Distribution

Type locality.

“ Leucosyrinx ” sansibarica Thiele, 1925

Fig. 34D–F

Leucosyrinx sansibarica Thiele, 1925: 181 (215), pl. 24 (36) fig. 1.

Brachytoma griffithii (not Gray, 1833) – von Martens 1904: 84. — Thiele 1904: 173, pl. 9 fig. 73. Leucosyrinx sansibarica – Powell 1969: 340 (23-404), pl. 258 fig. 5.

Type material

Syntypes

EAST AFRICA • 2 specs; Pembakanal; 5°24′ S, 39°19′ E; depth 818 m; Valdivia, stn 246 (2 dead); ZMB ?.

GULF OF ADEN • 2 specs; 13°2′ N, 46°41′ E; depth 1469 m; Valdivia, stn 271; ZMB Mol 60089, ZMB Mol 109387 .

Remarks

The species was established for Brachytoma griffithii sensu von Martens (1904) , not Gray, 1833. Von Martens (1904) cited material from two Valdivia stations: station 246 (Pemba Channel, off Zanzibar) and station 271 in the Gulf of Aden. Two dead specimens were collected at the first station, while several live specimens were collected at station 271. Thiele (1904: 173, pl. 9 fig. 73) illustrated the radula of the species without indicating the exact specimen, describing a radula typical of Comispira with a large central formation. Von Martens (1904) proposed a variety, gracilior, for specimens from off Zanzibar. When Thiele (1925) renamed the species Leucosyrinx sansibarica , he did not designate a holotype or a type series, nor did he provide a formal description, but from the specific epithet, it can be inferred he referred to the specimens from station 246. His illustration aligns with var. gracilior as described by von Martens, 1904 (“Martens distinguished a var. gracilior , which I have illustrated in Figure 1 .”—my translation).

We were unable to examine the specimens from the station 246, but the specimens from the station 271 in the Gulf of Aden are not conspecific. While one specimen represents the typical Leucosyrinx (ZMB Mol 60089, Fig. 34E ), the other, with a row of subsutural knobs, belongs to Comispira (ZMB Mol 109387, Fig. 34F ), rather similar to C. obtusigemmata (see below). The specimen illustrated by Thiele (1925) ( Fig. 34D ) is generally similar to the specimen of Leucosyrinx from the Gulf of Aden ( Fig. 34E ), differing mainly in its slenderer shell (a variable intraspecific character in Leucosyrinx ) and a much shallower anal sinus. It should be noted that in several of Thiele’s (1925) line drawings, the illustrated anal sinus does not match the actual sinus in the same specimen. We therefore consider L. sansibarica as belonging to the genus, although a final decision requires examining the illustrated specimen (currently unavailable) and designating a lectotype.

Distribution

Tanzania to Gulf of Aden, 818–1469 m.

Species excluded from Leucosyrinx and Comitas

As demonstrated here, previously to the current work, there was no clear distinction between Leucosyrinx and Comitas . Numerous species of Leucosyrinx were erroneously attributed to Comitas by Powell (1969) and are reallocated in this work. The following Indo-Pacific species were previously attributed to either Leucosyrinx or Comitas , but we are excluding them on different grounds. The species are listed in alphabetical order by their specific epithet. The species that we consider as belonging to Comitas are not treated here.

Figures

Fig. 33. Types of species of Leucosyrinx Dall, 1889 known only from empty shells. A. L. palawanica (Powell, 1969) comb. nov., holotype USMNM 237910, SL 43.5 mm. B–D. L. paupera (Watson, 1881) comb. nov. B. Lectotype, NHMUK 1887.2.9.1009, SL 40.1 mm. C. Paralectotype NHMUK 1887-2-9- 1010, SL 33.3 mm (= Borsoniidae, genus and species uncertain). D. Paralectotype NHMUK 1887-2-9- 1011, SL 18.5 mm (= L. arcana). E. L. undosa (Schepman, 1913) comb. nov., holotype, NATURALIS, ZMA.MOLL.136841, SL 29.5 mm (photo courtesy of K. Hasegawa).F. L. erilda (Dall, 1908), holotype, USNM 123091, SL 18 mm (photo courtesy of USNM). G. L. powelli (Rehder & Ladd, 1973), holotype, USNM 703267, SL 13.0 mm (photo courtesy of USNM). H. L. suratensis (Thiele, 1925), holotype, ZMB Moll 60072, SL 16.6 mm (photo courtesy of Museum für Naturkunde). Shells not to scale.

Fig. 34. A–F. Doubtful species of Leucosyrinx Dall, 1889. A. “Leucosyrinx” caecilia Thiele, 1925, holotype, ZMB Mol 109385, SL 7.5 mm (photo courtesy of Museum für Naturkunde). B. “Leucosyrinx” canyonensis (Dell, 1956), holotype, MNZ, M.009262, SL 9.3 mm (photo from the website of MNZ, https://collections.tepapa.govt.nz/object/151638). C. “Leucosyrinx” erna Thiele, 1925, syntype, ZMB Mol 109384, SL 7.8 mm (photo courtesy of Museum für Naturkunde). D–F. “Leucosyrinx” sansibarica Thiele, 1925. D. Original drawing (Thiele 1925: pl. 24 (36) fig. 1),? ZMB, SL 45 mm. E. Syntype, ZMB Mol 60089, Gulf of Aden, SL 42.6 mm (photo courtesy of Museum für Naturkunde). F. Syntype, ZMB Mol 109387, Gulf of Aden, SL 34.5 mm (= Comispira) (photo courtesy of Museum für Naturkunde). G–H. Types of species excluded from Leucosyrinx and Comitas H.J. Finlay, 1926. G. Rhodopetoma amycus (Dall, 1919) comb. nov., holotype, USNM 226163, SL 21.5 mm (photo courtesy of USNM). H. Burchia clionella (Dall, 1908), syntype, USNM 123125, SL 35.2 mm (photo courtesy of USNM).

Fig. 1. Bayesian phylogenetic tree obtained with the cox1 dataset. Posterior probabilities (> 0.80) are shown for each node. The SSH containing several specimens are collapsed for saving space, the number in brackets indicates the number of specimens in the corresponding collapsed clade.