Fusinus laviniae, Snyder, Martin Avery & Hadorn, Roland, 2006

Snyder, Martin Avery & Hadorn, Roland, 2006, A new bathyal Fusinus (Mollusca: Gastropoda: Fasciolariidae) from New Caledonia, Zootaxa 1311, pp. 1-12 : 4-11

Fusinus laviniae sp. nov.

( Figs 1–13 , 21 )

Description

Shell fusiform, of medium size for genus (to 115 mm), about 11 whorls including protoconch, with elongate, slender spire, conspicuously long, slender, sometimes wavy neck. Upper whorls convex, lower whorls distinctly carinated, with straight or slightly concave shoulder slope. Suture distinct, adpressed, with narrow subsutural band. Protoconch smooth, glossy, white, about 1 1/2 whorls. First whorl usually conspicuously bulbous, often larger than second whorl. Final half whorl ornamented with numerous close­set fine axial riblets. Transition to teleoconch abrupt, with distinct varix. Maximum protoconch diameter approximately 1.1 mm.

7–9 broad convex axial ribs on upper teleoconch whorls, reaching from suture to suture. Interspaces on earlier whorls rather narrow, about ¼ rib width, widening to about the width of a rib by the fifth teleoconch whorl, retaining that relationship to the body whorl. Axial ribs usually becoming weaker, reduced to pointed peripheral knobs on lower whorls, 9–12 per whorl. Five major spiral cords on early teleoconch; peripheral cord strongest, cord below peripheral cord slightly weaker, cords on shoulder weak. 5–6 major spiral cords from second or third whorl on. Weak intercalated spiral threads from third teleoconch whorl on; up to 7 on body whorl, with central one strongest. Aperture white, ovate, pinched at both ends, with well­developed posterior notch. 15–20 distinct spiral lirae on labral wall of aperture; outer lip shows determinate growth, with thickened margin in adults. Lip margin bears weak denticles. Margin of parietal shield occasionally slightly flaring, shield white, thick, glossy, irregularly wrinkled, and reflecting somewhat underlying spiral sculpture. Siphonal canal about 41.6% of shell length (n=16, range (0.25–0.47)), slender, sometimes slightly sinuous, tapering anteriorly. Outer face of neck ornamented with major spiral cords and intercalated minor threads, becoming weaker towards distal end.

Shell cream­white overall; axial ribs, knobs on shoulder usually red­brown. Major spiral cords at shoulder, on neck occasionally tinged red­brown. Periostracum pale brown, velvety. Operculum typical of genus, brown, corneous, solid, filling aperture, with terminal nucleus. Radula ( Figs. 8 c–8e), from subadult specimen (91.3 mm, MNHN), with tricuspid central tooth, cusps of about equal size, projecting below base. Top narrower than base, sides concave. Lateral teeth curved, with eight long pointed cusps, single small denticle at either end. Morphometric data for all examined specimens is recorded in table 1.

Etymology

This species is named in honor of Ms. Lavinia Smerconish, who was recently instrumental in obtaining a scientifically important collection of shells for the Academy of Natural Sciences of Philadelphia.

Discussion

Five other Fusinus species are known from around New Caledonia. The occurrence of Fusinus nobilis in the present material, previously known from the Philippine Islands (specimen in SC), represents a new range record. Fusinus laviniae can be differentiated readily from all of these species, which are here treated in alphabetical order. Differentiation is also given from Fusinus colus . Although the latter species is widespread throughout the Indo­Pacific, we have not seen material from New Caledonia. Shallowwater species seem to be rarely collected around New Caledonia and are not well represented in museum collections.

Lengths are given in mm; localities referenced are as follows:

L 1: North Grand Passage area, North Belep Islands [19°45’S, 163°40’E]. L 2: North New Caledonia, SMIB 6 stn DW 108, 19 °07’S, 163°30’E. L 3: North New Caledonia, SMIB 6 stn DW 109, 19 °06’S, 163°30’E. L 4: North New Caledonia, SMIB 6 stn DW 127, 19 °07’S, 163°23’E. L 5: North New Caledonia, SMIB 6 stn DW 130, 19 °05’S, 163°21’E. L 6: North New Caledonia, BATHUS 4 stn DW 933, 19 °07’S, 163°29’E. L 7: North New Caledonia, BATHUS 4 stn CP 950, 20 °32’S, 164°56’E. L 8: South New Caledonia, NORFOLK 1 stn DW 1737, 22 °52’S, 167°12’E. L 9: Southwest New Caledonia, BATHUS 2, [no further data available]. L 10: South New Caledonia, Vauban stn 41, 22 °10’S, 167°05’E. L 11: South New Caledonia, [no further data available]. L 12: New Caledonia, South Norfolk Ridge, Jumeaux Seamount.

Fusinus colus ( Figs. 14, 15 ) —This quite variable species is more elongate (length:width, 4.6, n=10 (range 3.89–5.16), compared to 3.5, n=16 (range 2.37–4.13)) than F. laviniae . The axial ribs on the early whorls are not as sharply carinate, and extend from suture to suture. The later whorl profiles are more rounded and convex than in F. laviniae . There are also somewhat atypical specimens of the genotype from Cuddalore, Bay of Bengal, southeast India, and from the Philippine Islands, which appear similar to F. laviniae in the later whorls. However, these specimens without exception show the characteristic suture­to­suture axial ribs with brownish coloration between them on the early teleoconch whorls. The examination of the early whorls will provide easy differentiation of these two species, even in this case.

Fusinus nicobaricus ( Fig. 19 ) —This species has been collected in New Caledonia by French expeditions. The thick rounded spiral cords and distinctive overlaid brown/black color pattern readily distinguish this species from all others collected around New Caledonia.

Fusinus nobilis ( Fig. 20 ) – Fresh live material was taken by the MUSORSTOM expeditions and is housed at MNHN. It closely resembles Reeve’s original description and figure (1847: pl.15, fig. 60). This is a larger species (generally over 200 mm when mature) than F. l a v i n i a e. The whorls are inflated with no sharp protuberances.

Fusinus salisburyi ( Fig. 16 ) – This species is discussed in Callomon & Snyder (2004). Although the range was given there as from Japan, Taiwan and Australia, MNHN has material taken by the expeditions off New Caledonia. This is another somewhat larger species (up to 215 mm) with more numerous and prominent spiral cords (11–13 compared to 5–6) than F. laviniae , and a distinctive ‘pseudoumbilicus’ ( Fulton 1930) formed by recurvature of the lower portion of the parietal shield. The axial lobes or knobs on F. salisburyi are not as angular or pronounced as on F. l a v i n i a e and the siphonal canal is straight.

Fusinus similis ( Fig. 18 ) —This species is discussed by Callomon & Snyder (2006). New Caledonia is the type locality, and material was collected by the MUSORSTOM expeditions in northeastern New Caledonia. There is also MNHN material collected in the neighboring Loyalty Islands. This species is somewhat larger (up to 183 mm) than F. laviniae . The aperture is distinctly quadrate and placed further toward the abapical end of the shell than in F. l a v i n i a e. The sutures of F. s i m i l i s are more sharply tilted with respect to the shell axis.

Fusinus undatus (Gmelin, 1791) —This species was also collected by the MUSORSTOM expeditions and the material is housed at MNHN. It is discussed in detail in Callomon & Snyder (2006). Fusinus undatus is both larger (up to 232 mm) and much heavier than F. laviniae , with an almost smooth and slightly glossy surface on the penultimate and body whorls. The peripheral sculpture in F. undatus consists of axial buttresses with rounded lower extremities, in distinction to the sharp angular shoulder knobs of F. l a v i n i a e.

Sharp proturbences on large slender fusinids are an uncommon occurrence. However, there are a few other fusinids with which this new species could possibly be confused.

Fusinus dovpeledi Snyder, 2002 —This species, collected at 300 m off Neviot, Egypt in the Red Sea, is about the same size as F. l a v i n i a e and has a similar long sinuous siphonal canal. The peripheral carinae on F. dovpeledi are not as prominent and number 12–14 on the body whorl compared to 9–12 in F. laviniae . Easy differentiation is provided by the spiral sculpture with approximately 12 strong cords on the later whorls compared to 5–6.

Fusinus malhaensis Hadorn, Fraussen & Bondarev, 2001 —This species, collected at 200–300 m on the Saya de Malha Bank in the western Indian Ocean, is larger (up to 175 mm) than F. laviniae with fewer (7–8 compared to 9–12) and less prominent carinae. Additionally, the parietal shield in F. malhaensis is usually flared and detached.

Figures

FIGURES 1 – 8. 1. Fusinus laviniae, sp. nov., Holotype, 114.5 mm SL, North Grand Passage area, North Belep Islands, 400 m (MNHN). 2. Paratype 1, 112.6 mm SL, L 1, 400 m (SC PT 1). 3. Paratype 2, 97.4 mm SL, L 2, 215 – 225 m (ANSP 413301). 4. Paratype 3, 85.3 mm SL, L 3, 705 – 750 m (HC). 5. Paratype 4, 82.0 mm SL, L 4, 190 – 205 m (AMS C. 205367). 6. 46.2 mm SL, L 12, 450 m (RC). 7. 90.5 mm SL, L 10, 260 – 280 m (MNHN). 8. 91.3 mm SL, L 9 (MNHN), including radula. 8 d: detail of central tooth. 8 c, 8 e: scale bar = 1 mm.

FIGURES 9 – 15. 9. Fusinus laviniae, sp. nov., 101.0 mm SL, L 6, 212 – 220 m (MNHN). 10. 73.9 mm SL, L 2, 210 – 220 m (MNHN). 11. 78.0 mm SL, L 5, 225 – 230 m (MNHN). 12. 64.0 mm SL, L 8, 343 – 400 m (MNHN). 13. 98.2 mm SL, southern New Caledonia, 200 m (HC). 14. Fusinus colus (Linnaeus, 1758), 172.0 mm, CORAIL 2 stn CP 130, 19 ° 27 ’ S, 158 ° 34 ’ E, 217 m (MNHN). 15. Fusinus colus 180.0 mm, CHALCAL stn CP 10, 20 ° 00 ’ 20 ” S, 158 ° 46 ’ 60 ” E, 225 m (MNHN).

FIGURES 16 – 21. 16. Fusinus salisburyi Fulton, 1930, 137.3 mm, SMIB 6 stn DW 121, 18 ° 58 ’ S, 163 ° 26 ’ E, 315 m (MNHN). 17. Fusinus salisburyi Fulton, 1930, 159.0 mm, CALSUB 1989, pl. 21, 22 ° 45 ’ S, 167 ° 09 ’ E, 340 m (MNHN). 18. Fusinus similis (Baird, 1873) 219.0 mm, Hienghêne, northeastern New Caledonia, 100 m (MNHN). 19. Fusinus nicobaricus (Röding, 1798) 98.0 mm, Ile Ouen­Baie du Prony, stn 99, 22 ° 33 ’ S, 166 ° 35 ’ E, 14 m (MNHN). 20. Fusinus nobilis (Reeve, 1847), 233.0 mm, LITHIST stn DW 12, 24 ° 45.7 ’ S, 168 ° 08.1 ’ E, 235 – 280 m (MNHN). 21. Fusinus laviniae, sp. nov., protoconch, 87.1 mm SL, L 12, 450 m (RC).