Clypeostoma salpinx (Barnard, 1964) Herbert, 2012

Herbert, D. G., 2012, A revision of the Chilodontidae (Gastropoda: Vetigastropoda: Seguenzioidea) of southern Africa and the south-western Indian Ocean, African Invertebrates 53 (2), pp. 381-381 : 404-408

Clypeostoma salpinx (Barnard, 1964) comb. n.

Figs 4D , 6B , 10 , 11

Turcica salpinx: Barnard 1964: 19 , fig. 3a–d; Kensley 1973: 44, fig. 112. Type loc. (here designated, see below): off Cape Morgan , Eastern Cape, South Africa, 77 fath. [- 141 m].

Description:

Shell: Trochoid-turbiniform, moderately elevated (L/D=1.25–1.50); teleoconch of 6–7 whorls; apical whorls convex, later ones more flat-sided; apical angle 60–70°; suture level with subperipheral cord, not itself channelled, but appearing so due to presence of a narrow sulcus below peripheral cord of preceding whorl, particularly pronounced on spire whorls; shell periphery rounded. First teleoconch whorl sculptured by somewhat sinuous axial pliculae; 3 spiral cords arise during second whorl and a fourth, beneath the adapical suture, during whorl three; sculpture of subsequent whorls comprising 4 (rarely five) spiral cords (not counting that level with abapical suture), these crossed by somewhat irregular, prosocline axial pliculae (30–40 on last adult whorl); cords with scale-like nodules where crossed by pliculae, those on uppermost (subsutural) cord frequently larger; intervals between cords slightly wider than cords themselves; cord intervals on last adult whorl occasionally with a weak intermediary cord. Base rounded, sculptured with ±6 spiral cords; cords somewhat weaker than those on apical surface, but similarly nodose; umbilicus closed in all but small juveniles (<4 whorls). Peristome markedly oblique, more or less in one tangential plane; aperture subcircular to D-shaped, flattened in the parietal region; columella lip with 2 teeth, the lower one well developed, the upper one less so; teeth bluntly rounded, separated by shallow concavity; parietal and umbilical region covered with well-developed, translucent, smooth, glossy callus; margin of callus raised and flaring basally, running smoothly into basal lip; callus with 1 or 2 small tubercles near base of lower columella tooth. Outer lip lacking external varix, but thickened internally and bearing up to 15 denticles; denticles ridge-like, more or less in a single row and usually alternating in strength, that nearest columella usually strongest and separated from basal columella tooth by a U-shaped notch; edge of outer lip flaring; interior highly nacreous, not spirally lirate (except at apertural thickening), but somewhat angled beneath cords of external surface.

Microsculpture ( Fig. 11B, C ): Early teleoconch whorls with vermiform spiral threads in intervals between axial pliculae; adult microsculpture of scratch-like marks, filled with intritacalx in fresh specimens, but this seldom well developed and usually obscured by superficial encrustations.

Protoconch ( Fig. 11A, C ): Translucent white to pale buff; diameter 360–380 µm; globose, strongly exsert and somewhat tilted; terminal lip convex with sinusigera-like beak in mid region; surface sculptured with a fine irregular granulation and a faint spiral thread midway between sutures.

Colour: Shell mostly uniform buff to pale orange-brown, occasionally nearly white; cord intervals with slight pink/green iridescence; some specimens with occasional slightly darker spots and blotches beneath suture and at edge of outer lip; live-collected specimens nearly always over-grown with a thin encrusting sponge ( Fig. 10E, F ).

Dimensions: Largest specimen (NMSA D4231), length 12.6 mm, diameter 9.0 mm; adult length mostly 11.0– 12.5 mm, but at the northern limit of the distribution specimens are considerably smaller (adult length 6–7 mm) ( Fig. 10G ).

Operculum ( Fig. 4D ): Initially tightly multispiral, but whorls broadening with growth and becoming more openly multispiral.

Radula ( Fig. 11D, E ): Formula ∞+3+1+3+∞, with ca 80 transverse rows of teeth; transition from lateral to marginal series not clearly defined. Rachidian shaft with well-developed lateral flanges creating a distinct hood, base of cusp with raised, transverse basal ridge, cusp apex acutely trigonal with a narrow median denticle and 3–5 smaller denticles on each side. Lateral teeth overlapping extensively, their cusps asymmetrically trigonal; central denticle large on first lateral, progressively decreasing in size on second and third; side denticles few on first lateral, but progressively more numerous on laterals 2 and 3. Marginals numerous, the inner ones slightly longer than the laterals, their tips relatively narrow and finely pectinate laterally; marginals progressively longer and more slender in middle of series then shorter with proportionately broader tips at radula margin.

External anatomy ( Fig. 6B ): Body uniformly yellowish white, no skin pigmentation evident in preserved specimens. Cephalic lappets well developed, almost meeting in mid-line, free margin with fine projections; right post-ocular peduncle present in both sexes, nearly as long or longer than eyestalk, with a faint dorsal groove, peduncle tip often flattened and expanded; no right subocular tentacle evident; snout with extensive ventro-lateral flanges extending well beneath neck lobes, mouth deeply split mid-ventrally; neck lobes broad, anterior two-thirds of right lobe with approx. 5 first-order tentacles with many smaller intermediaries, posterior third minutely fimbriate; anterior three-quarters of left lobe with approx. 10 tentacles in a variety of sizes, posterior quarter more or less smooth; epipodium bearing approx. 7 relatively large, first-order tentacles (not all the same size) with many, very much smaller intermediaries; larger epipodial tentacles usually with an indistinct basal sense organ; no epipodial sense organs evident beneath neck lobes.

Type material: Two syntype lots of Turcica salpinx Barnard, 1964 ( SAMC): SOUTH AFRICA: off Cape Morgan, 77 fath. [- 141 m], 1 broken adult (A9252); off Hood Point , 49 fath. [- 90 m], 2 juvenile, 1 immature, 3 fragments (A9253) .

Material examined (all NMSA unless indicated otherwise): MOZAMBIQUE: Inhambane transect, Campagne MAINBAZA, dredged RV Vizconde de Eza, st’n CP3143 (23.533°S 35.767°E) , living, - 264–277 m, 11.iv.2009 ( MNHN); ditto, st’n CP3144 (23.55°S 35.68°E) , living, - 171–180 m, 16.iv.2009 ( MNHN); between Inhaca and Inhambane (approx. 25.1°S 34.8°E) , - 225–300 m, lobster traps, J. Rosado, v.1996 (L8399); southern Mozambique [not further localized], living , - 250 m, don. F. Amorim, v.1990 (K7361). SOUTH ARICA: KwaZulu-Natal: off Island Rock (27.2800°S 32.8233°E) , - 400 m, sandstone boulders, dredged NMDP, RV Meiring Naude, st’n ZE5, 5.vi.1987 (D6150); NE of Leven Point (27.8983°S 32.6567°E) , - 260 m, sponges, stones, dredged NMDP, RV Meiring Naude, st’n ZL6, 9.vi.1988 (E4447); off Cape Vidal off (28.1383°S 32.6150°E) , - 200 m, sponge rubble, dredged NMDP, RV Meiring Naude, st’n ZM9, 11.vi.1988 (E3941); SE of Neill Peak [ Cunge Hill ] (28.7400°S 32.5367°E) , - 320–340 m, sandy mud, dredged NMDP, RV Meiring Naude, st’n ZP5, 12.vi.1988 (E3979); SE of Port Durnford (29.0150°S 32.2017°E) , - 215 m, glutinous sandy mud, dredged NMDP, RV Meiring Naude, st’n ZQ8, 13.vi.1988 (E3123); ditto (29.0250°S 32.1967°E) , - 310–320 m, glutinous sandy mud, dredged NMDP, RV Meiring Naude, st’n ZQ9, 13.vi.1988 (E3167); off Glenton Reef (29.2450°S 32.0370°E) , - 200–210 m, sandy mud, dredged NMDP, RV Meiring Naude, st’n ZRR9, 18.vi.1989 (S457); off Matigulu River mouth (29.3567°S 31.9417°E) , - 145 m, mud, shell rubble, dredged NMDP, RV Meiring Naude, st’n ZR7, 16.vi.1989 (E8788); ditto (29.3650°S 31.9367°E) , - 200–220 m, mud and coarse sand with Dendrophyllia , dredged NMDP, RV Meiring Naude, st’n ZR9, 16.vi.1989 (E9014); off Umhlanga Rocks (29.7499°S 31.1685°E) , 59 fath. [- 107 m], dredged A.D. Connell, 7.vii.1983 (B6296); off Durban (29.8333°S 31.2367°E) , living, - 130 m, sandstone gravel and some rocks, dredged NMDP, RV Meiring Naude, st’n XX115, 9.vii.1986 (D4231); ditto (29.8400°S 31.2333°E) , living, - 150 m, sandstone gravel and some sponge, dredged NMDP, RV Meiring Naude, st’n XX114, 9.vii.1986 (D4146); off Umlaas Canal (30.0133°S 31.0600°E) , - 150 m, muddy sand and fine pebbles, dredged NMDP, RV Meiring Naude, st’n XX75, 10.vii.1985 (D1155); ditto (30.0183°S 31.0533°E) , living, - 150 m, coarse sand and pebbles with numerous spatangoids, dredged NMDP, RV Meiring Naude, st’n XX70, 9.vii.1985 (E7597, D796); ditto (30.0317°S 31.0450°E) , - 150 m, coarse sand, dredged NMDP, RV Meiring Naude, st’n XX72, 10.vii.1985 (D859); ditto (30.0367°S 31.0650°E) , living, - 250 m, coarse sand, dredged NMDP, RV Meiring Naude, st’n XX67, 9.vii.1985 (D1449); off Amanzimtoti (30.0783°S 31.0550°E) , - 300–305 m, medium sand, dredged NMDP, RV Meiring Naude, st’n XX66, 9.vii.1985 (D1315); ditto (30.0883°S 31.0417°E) , - 260–270 m, medium sand, dredged NMDP, RV Meiring Naude, st’n XX65, 9.vii.1985 (D1180); ditto (30.0967°S 30.9950°E) , living, - 115–125 m, medium sand, dredged NMDP, RV Meiring Naude, st’n XX61, 9.vii.1985 (D1267); ditto (30.1000°S 31.0267°E) , living, - 245–250 m, medium sand, dredged NMDP, RV Meiring Naude, st’n XX64, 9.vii.1985 (D1663); ditto (30.1067°S 31.0133°E) , - 160–170 m, medium sand, dredged NMDP, RV Meiring Naude, st’n XX62, 9.vii.1985 (D1489); off Park Rynie (30.3838°S 30.8355°E) , living, - 140 m, some sand, sponge rubble, dredged NMDP, RV Meiring Naude, st’n X6, 19.viii.1981 (C1590); ditto (30.3838°S 30.8350°E) , living, - 140 m, some sand, sponge rubble, dredged NMDP, RV Meiring Naude, st’n X7, 19.viii.1981 (C1628); Port Edward , slightly north of (31.0967°S 30.3133°E) , living, - 140 m, live sponges, dredged NMDP, RV Meiring Naude, st’n XX57, 8.vii.1985 (D1402); off Port Edward (31.1067°S 30.3000°E) , living, - 125 m, living sponges, dredged NMDP, RV Meiring Naude, st’n XX58, 8.vii.1985 (D906); ditto (31.1133°S 30.2967°E) , living, - 120–125 m, living sponges, dredged NMDP, RV Meiring Naude, st’n XX59, 8.vii.1985 (D1358, E7372); ditto (31.1400°S 30.2766°E) , living, - 160 m, sponge, gorgonians and sand, dredged NMDP, RV Meiring Naude, st’n A18, 7.vii.1986 (C9650, S3190); ditto (31.1650°S 30.2516°E) , living, - 140 m, sponge rubble, dredged NMDP, RV Meiring Naude, st’n A6, 18.viii.1981 (E225). Eastern Cape: off Mtentu River (31.2333°S 30.1833°E) , living, - 150–160 m, sponges rocks, dredged NMDP, RV Meiring Naude, st’n XX12, 15.vi.1983 (C5225); off Msikaba River (31.3867°S 30.0433°E) , living, - 100 m, sponge rubble, dredged NMDP, RV Meiring Naude, st’n C3, 12.viii.1981 (C1125, E192); ditto (31.4166°S 29.9833°E) , - 150 m, sponge, gorgonians, dredged NMDP, RV Meiring Naude, st’n D23, 2.vii.1986 (C9808); off Port Grosvenor (31.4166°S 29.9666°E) , living, - 95–100 m, coarse sand, very gorgonians, dredged NMDP, RV Meiring Naude, st’n D12, 16.viii.1981 (E209); ditto (31.4166°S 29.9333°E) , - 80–84 m, calcareous nodules, sand, dredged NMDP, RV Meiring Naude, st’n D19, 16.viii.1981 (E196); ditto (31.4317°S 29.9650°E) , - 120–128 m, coarse sand, some mud, solitary coral, shells, dredged NMDP, RV Meiring Naude, st’n D2, 13.viii.1981 (C1151); off Waterfall Bluff (31.5017°S 29.9200°E) , living, - 200 m, some sponges, rocks, dredged NMDP, RV Meiring Naude, st’n E10, 4.vii.1986 (C9837); off Mgazi River (31.7283°S 29.5317°E) , - 140–145 m, glutinous black mud, dredged NMDP, RV Meiring Naude, st’n J13, 4.vii.1985 (C9304, S3192); off Rame Head (31.8450°S 29.4750°E) , living, - 150–160 m, some sponges, dredged NMDP, RV Meiring Naude, st’n K10, 20.vii.1982 (C1896); ditto (31.8583°S 29.4683°E) , living, - 170–200 m, sandstone, yellow hydroids, dredged NMDP, RV Meiring Naude, st’n K11, 20.vii.1982 (C1911); off Ubombo Head (31.9050°S 29.2967°E) , living, - 60–62 m, coarse sand, oyster shell conglomerate, dredged NMDP, RV Meiring Naude, st’n L4, 16.vii.1982 (E248); ditto (31.9700°S 29.3900°E) , living, - 200 m, smooth bedrock, living sponges, dredged NMDP, RV Meiring Naude, st’n L11, 8.vii.1985 (C8970); off Whale Rock (31.9800°S 29.2800°E) , living, - 90 m, sponge rubble, coarse sand, some rocks, dredged NMDP, RV Meiring Naude, st’n M12, 3.vii.1985 (C9502); ditto (32.0166°S 29.3166°E) , living, - 150–200 m, sponge rubble, dredged NMDP, RV Meiring Naude, st’n M8, 20.vii.1982 (E289); ditto (32.0283°S 29.3050°E) , living, - 150–165 m, some coarse sand, discoid corals, dredged NMDP, RV Meiring Naude, st’n M9, 20. vii.1982 (C2313); ditto (32.0333°S 29.3166°E) , living, - 200–210 m, sponge rubble, some sandstone rocks, dredged NMDP, RV Meiring Naude, st’n M13, 3.vii.1985 (C9276); off Mncwasa Point (32.1033°S 29.1083°E) , - 68 m, sand, dredged NMDP, RV Meiring Naude, st’n N8, 10.vii.1982 (E337); off Nthlonyane River (32.2183°S 28.9950°E) , - 80 m, sand, broken shell, dredged NMDP, RV Meiring Naude, st’n P6, 17.vii.1982 (C2577); ditto (32.2400°S 29.0233°E) , living, - 95 m, sponge rubble, dredged NMDP, RV Meiring Naude, st’n P4, 17.vii.1982 (E329); ditto (32.2567°S 29.0133°E) , living, - 90–95 m, lithothamnion pebbles, dredged NMDP, RV Meiring Naude, st’n P5, 17.vii.1982 (C2565); ditto (32.2750°S 29.0100°E) , living, - 240 m, sponge rubble, dredged NMDP, RV Meiring Naude, st’n P1, 17.vii.1982 (C3305); ditto (32.2867°S 29.0817°E) , living, - 220–230 m, branching sponges, gorgonians, dredged NMDP, RV Meiring Naude, st’n P2, 17.vii.1982 (C3300, E264); off Mbashe River (32.3033°S 29.0683°E) , living, - 200–220 m, sponge rubble, dredged NMDP, RV Meiring Naude, st’n Q1, 18.vii.1982 (V1944); off Qora River (32.3967°S

28.8117°E), living, - 196 m, sponge, dredged NMDP, RV Meiring Naude, st’n U9, 14.vi.1983 (C5154); off Nqabara Point off (32.4533°S 28.9317°E), living, - 250 m, live sponges with some corals, dredged NMDP, RV Meiring Naude, st’n S10, 12.vii.1984 (V4056) ; ditto (32.4550°S 28.9267°E), living, - 210 m, live sponges, dredged NMDP, RV Meiring Naude, st’n S9, 11.vii.1984 (W7627) ; off Shixini Point (32.4900°S 28.8967°E), living, - 240 m, sponge rubble, some sandstone, dredged NMDP, RV Meiring Naude, st’n T11, 11.vii.1984 (C6301) ; ditto (32.5233°S 28.8650°E), - 240 m, sand and old rubble, dredged NMDP, RV Meiring Naude, st’n T13, 11.vii.1984 (C6342) ; off Qora River (32.5633°S 28.8067°E), living, - 150–168 m, stones and sponges, dredged NMDP, RV Meiring Naude, st’n U7, 14.vi.1983 (C5095) ; ditto (32.5700°S 28.6567°E), - 400 m, sand, dredged NMDP, RV Meiring Naude, st’n U8, 14.vi.1983 (C4877) ; off Sandy Point (32.6233°S 28.6150°E), - 90 m, coarse sand, dredged NMDP, RV Meiring Naude, st’n W1, 11.vi.1983 (V2882) ; off Stony Point (32.6250°S 28.7333°E), living, - 150–152 m, calcareolite and coral, dredged NMDP, RV Meiring Naude, st’n V9, 14.vi.1983 (C4371) ; off Qolora River (32.7733°S 28.5900°E), living, - 174 m, sponge rubble, dredged NMDP, RV Meiring Naude, st’n Y2, 12.vi.1983 (C4637) ; ditto (32.7633°S 28.6067°E), living, - 240–250 m, live sponges, dredged NMDP, RV Meiring Naude, st’n Y9, 14.vii.1984 (C7131).

Type locality: Barnard’s type material originated from two Pieter Faure stations, but he did not select one in particular as the type locality. The given data for one of these stations (off Hood Point ( East London ), 49 fath. [- 90 m]) has since been shown to be erroneous ( Herbert 1987: 344). In this instance, the Hood Point locality is not far out of the known range of the species, but for other taxa it is widely so. The dredge haul was more probably taken off Durban. In view of this inaccuracy I here select the provenance of Barnard’s other type lot, off Cape Morgan [close to mouth of Great Kei River] 77fath. [- 141 m], as type locality .

Distribution and habitat ( Fig. 8 ): South-eastern Africa; from southern Mozambique (Inhambane) to the Great Kei River, Eastern Cape, South Africa; - 60–400 m, living specimens - 60–277 m, on hard substrata with abundant marine growths, particularly sponges.

Remarks: When compared to other species here transferred to Clypeostoma , C. salpinx differs from C. meteorae , C. nortoni and C. townsendianum in having slightly flatter whorls, commonly four rather than five or six spiral cords above the suture, fewer tubercles on the callus shield near the basal columella tooth, less elongate, more widely spaced denticles inside the outer lip and a more extensive inductural callus. C. elongata Vilvens, 2001 from Indonesia and C. reticulatum are both considerably larger, have coarser sculpture and more robust columella teeth. Within southern Africa, juvenile C. salpinx may be confused with those of Danilia textilis , but the latter have finer, more regularly cancellate sculpture, a sunken rather than an exsert protoconch and more rounded whorls with a more narrowly channelled suture.

Specimens from the northern limit of the distribution (off Inhambane) are surprisingly small, almost half the size South African specimens ( Fig. 10G ). However, this is the only significant conchological difference between this material and typical C. salpinx , and I consider it to be insufficient evidence upon which to base the description of a new species. Other species of Clypeostoma also exhibit considerable variation in size at maturity.

Figures

Fig. 4. Operculum morphology in the Chilodontidae: (A) Littorina littorea (Linnaeus, 1758), Cancale, Brittany,France,max.diameter 10.2mm (NMSA G778);(B) Euchelus asper (Gmelin,1791),Bombay, India,max.diameter 9.0 mm (NMSA J8066);(C) Granata sulcifera, Mtwalume,KZN, max.diameter 3.58 mm (NMSA V3927); (D) Clypeostoma salpinx, off Whale Rock, Eastern Cape, max. diameter 2.59 mm (NMSA C9502); (E) Danilia textilis, max. diameter 2.97 mm (holotype, NMSA E7756/ T2595); (F) Ascetostoma providentiae, off Boteler Point, KZN, max. diameter 2.52mm (NMSA S4904); (G) Herpetopoma (s.s.) instrictum, Low Isles, GreatBarrier Reef, Queensland,max.diameter 3.17 mm (AMS C.304699); (H) H. (s.s.) scabriusculum, Bradleys Head, Sydney Harbour,Australia, max. diameter 1.78 mm (AMS C.30695); (I) H. (s.l.) helix, off Umzinto, KZN, max. diameter 1.01 mm (NMSA D5427); (J) Vaceuchelus cretaceus, SE of Kosi Bay, KZN, max. diameter 2.52 mm (paratype, NMSA S4006/T2638); (K) V. natalensis, off Umzinto, KZN, max. diameter 0.99mm (NMSA D5428); (L) V.semilugubris, Réunion, max. diameter 1.28 mm (M.Jay coll’n MNHN); (M) Perrinia angulifera, off Boteler Point, KZN, max. diameter 4.44 mm (NMSA D9209); (N) P.konos, off Port Grosvenor, Eastern Cape, max. diameter 1.23 mm (NMSA E177); (O) P.stellata, Kosi Bay main coral reef, KZN, max. diameter 1.14 mm (NMSA S1985).

Fig.6. External anatomy of Chilodontidae.Schematic illustrations of the external features of the head-foot, viewed from above:(A)Ascetostoma providentiae (Melvill,1909);(B) Clypeostoma salpinx (Barnard, 1964); (C) Danilia textilis sp.n.; (D) Granata sulcifera (Lamarck,1822); (E) Perrinia angulifera (A. Adams, 1853); (F) Vaceuchelus cretaceus sp. n.; (G) V. natalensis (Smith, 1906).

Fig. 10. Clypeostoma salpinx (Barnard, 1964): (A–C) live-collected adult specimen cleaned of superficial encrustations, north of Port Edward, KZN, length 11.3 mm (NMSA D1402); (D) elevated specimen, off Nthlonyane River, Eastern Cape, length 11.3 mm (NMSA C3300); (E) basal view of specimen with well-developed apertural dentition and callus shield, off Nthlonyane River, Eastern Cape, diameter 8.25 mm (NMSA C3300); (F) live-collected specimen covered with encrusting sponge, off Nthlonyane River, Eastern Cape, length 9.8 mm (NMSA C2565); (G) dwarf adult specimen (apex missing), Inhambane, Mozambique, length 6.25 mm (MNHN).

Fig. 11. Clypeostoma salpinx (Barnard, 1964): (A) apical whorls showing exsert protoconch, bar = 500µm (NMSA E289); (B) adult microsculpture,bar = 50µm (NMSA E289); (C)protoconch with sinusigeralike projectionon terminallip,bar = 100 µm (NMSA E289); (D)radula,central field and left marginals, bar = 50 µm (NMSA C2313); (E) radula, rachidian and lateral teeth, bar = 25 µm (NMSA C2313). All dredged off Whale Rock, Eastern Cape, South Africa.

Fig. 8. Distribution of Clypeostoma species in the south-western Indian Ocean. C. meteorae (squares), C. cf. nortoni (circles), C. reticulatum (cross) and C. salpinx (triangles). Each symbol represents one or more records.