Benthofascis pseudobiconica, Tucker & Tenorio & Stahlschmidt, 2011

Tucker, J. K., Tenorio, M. J. & Stahlschmidt, P., 2011, The genus Benthofascis (Gastropoda: Conoidea): A revision with descriptions of new species, Zootaxa 2796 (1), pp. 1-14 : 7-9

Benthofascis pseudobiconica new species

Figures 2 , E–K; 4 , E & F

Type material. Holotype: MNHN 23069, 39.8mm x 12.8 mm, off Cape Moreton , Queensland, Australia . Paratypes: USNM 902891 , 2 specimens from the Indian Ocean of South Australia ; USNM 845059 , 2 specimens from 80 fathoms, Stradbroke Island , Moreton Bay, Queensland, Australia ; ANSP 424978 , 4 specimens from 100 fathoms, off Cape Moreton , Queensland, Australia ; ANSP 303729 , 2 specimens from 80 fathoms, off Cape Moreton , Queensland, Australia ; SMF 335128 , 1 specimen from trawlers at 200 m, on sand and rubble, off Bundaberg , central coast of Queensland, Australia ; SBMNH 424098 , 1 specimen from shell dredge at 160 m, east of Mooloolaba , southern Queensland, Australia ; Peter Stahlschmidt collection, 2 specimens from 100–120 m, off Capricorn Channel , Queensland, Australia ; AMS C.110615, 2 specimens from 132–155 m, off Mooloolaba , Queensland , 26º40'S, 153º36'E; AMS C.392807, 2 specimens from 128–183 m, E of Caloundra , Queensland , 26º48'S, 153º, 35'E; AMS C.373105, 2 specimens from 71–77 m, 5.7 km E of Mistral Point, Sydney , New South Wales , 33º56.470'S, 151º19.630'E (wet).

Other specimens. AMS C.383084, 4 specimens from 216–227 m, off Swain Reefs, off Hixson Cay , Queensland, 22º33'S, 153º26'E ; AMS C.468236, 1 specimen from 115–176 m deep, East of Moreton Bay , Queensland, 26º55'S, 153º33'E , dredged 1969; AMS C.111073, 2 specimens from 201 m, off S end of Fraser Island , Queensland, 27º57'S, 153º51.050'E ; AMS C.388791, 2 specimens from 66m, 5.6 km E of North Head, Sydney , New South Wales, 33º49.600S, 151º21.700E , dredged 18 January 1973, station SBS 21; AMS C.397151, 2 specimens from 128–137 m, off Tweed Heads , New South Wales, 28º19'S, 153º50'E ; AMS 392811 , 5 specimens from 187 m, SE of Swain Reefs , Queensland, 22º20.2'S, 153º17.130'E ; AMS C.388787 3 specimens from 66 m, 5.6 km E of North Head, Sydney , New South Wales, 33º49.5'S, 151º21.8'E , dredged 26 April 1973, station SBS 1; AMS C.373099, 3 specimens from 71–77 m, 5.7 km E of Mistral Point, Sydney , New South Wales, 33º56.470'S, 151º19.630'E (wet) ; AMS C.388789, 11 specimens from 71–77 m, 5.7 km E of Mistral Point, Sydney , New South Wales, 33º56.470'S, 151º19.630'E , dredged, 20 July 1972, Station: SBS 2; AMS C.388794, 10 specimens from 115–176 m deep, East of Moreton Bay , Queensland, 26º55'S, 153º33'E , dredged 1969; AMS C.110614, 5 specimens from 101–128 m, East of Caloundra , Queensland, 26º45'– 26º50'S , 153º34'– 153º36'E; AMS C.101223, 6 specimens from 128–183 m, 12–15 miles NNE of Cape Moreton , Queensland, 27º00'S , 153º34'– 153º36'E; AMS C.388788, 3 specimens from 115–175 m, off Moreton Bay , Queensland, 27º10'S , 153º, 40'E; AMS C.372589, 3 specimens from 9 m, Twofold Bay , New South Wales, 37º5'S, 149º55'E ; AMS C.468231, 1 specimen from 201 m, off S end of Fraser Island , Queensland, 27º57'S, 153º51.050'E ; AMS C.388782 4 specimens from 73 m, off Tweed Heads , New South Wales, 28º17'S, 153º44'E ; AMS C.468234 1 specimen from 71–77 m, 5.7 km E of Mistral Point, Sydney , New South Wales, 33º56.470'S, 151º19.630'E (wet) ; ANSP 310029 , 4 specimens from 100 fathoms, off Cape Moreton , Queensland, Australia ; SBMNH 424099 , 1 specimen from shell dredge at 160 m, east of Mooloolaba , southern Queensland, Australia .

Type locality. Cape Moreton , Queensland, Australia

Range. Queensland and New South Wales, Australia .

Description. Shell moderate in size, up to 42.4 mm long, solid, ovate-fusiform. We examined a total of 42 specimens that could be accurately measured. These averaged 27.8 mm long (range = 12.8–42.4 mm). They averaged 9.9 mm wide (range = 5.7–14.9 mm). Color pattern is banded with tan to yellow bands separated by areas of white. Three colored bands are present on the teleoconch whorls with one at the shoulder, one near midbody and the other at the anterior end. Sutural ramp has a colored band at the suture and a white area anterior to the colored band. Larger specimens have 6.7 to 7 whorls including the protoconch. Sculpture on the protoconch consists of fine spiral grooves. There are more than 4 spirals on the early to middle teleoconch sutural ramps. The spirals and axials are of the same size and do not produce a punctate appearance. The number of spirals is reduced on the outer teleoconch sutural ramps to two or three that are crossed by growth lines. The teleoconch is ornamented by closely set spirals separated by narrow interspaces. The sides of the body whorl are slightly convex but not flattened. The shoulders are indistinct. The aperture is narrow with a deep sinus, the lip is thin, straight and is produced medially. Inner shell walls are resorbed ( Fig. 2K ). The columella is nearly straight. There is a groove near its posterior end just where the columella meets the body whorl. This forms a denticle inside the aperture. The anal sinus is not symmetrical and is deepest at the suture. The protoconch is paucispiral, blunt and swollen looking. The operculum is leaf-shaped with a terminal nucleus. It is fairly large and covers most of the apertural opening. The operculum of a specimen (AMS C.373099) with a shell length of 17.3 mm measured 3.65 mm in length. Previous drawings of the radula suggested that it is simple with a barb and blade (see Powell 1966; Tucker & Tenorio 2009, as B. biconica ). However, the tooth has more internal structure than previously known ( Figs. 4E & F ). The barb is blunt tipped and is about one-third as long as the blade. The distal end of the blade is elevated above the shaft of the tooth and slopes to meet the tooth shaft. There is no anterior fold but there is a C-fold. This fold demonstrates that the tooth is enrolled a minimum of 360 degrees. There are no serrations and no terminating cusp. There is a fold on the shaft of the tooth that begins posterior to the distal end of the blade. This fold extends to the waist of the tooth ( Fig. 4E ). The tooth has a slight but distinct waist.

Discussion. This species has been confused with Benthofascis biconica ( Figs. 1A–C ), which it does resemble. The comparison to B. biconica is given under that species but in summary the two can be separated by body whorl shape and ornamentation of the first two whorls. In B. biconica the shoulders are more angular than in B. pseudobiconica . The early whorls of B. biconica have spirals and axials strongly developed, whereas in B. pseudobiconica the axials are hardly developed at all initially. B. angularis ( Figs. 2A & C ) has even more angular shoulders than does B. pseudobiconica .

Etymology. The name underscores the similarities that the new species shares with Benthofascis biconica .

Figures

FIGURE 1. A–C. Holotype of Benthofascis biconica (AMS C.016448, 35–37 m deep, Shoalhaven Bight, New South Wales, Australia), height 18 mm, width 8 mm, ventral (A) and side (B) views with enlargement of spire (C). D–E. Benthofascis biconica (AMS C.468235, 5.7 km E of Mistral Point, Sydney, New South Wales, 33º56.470'S, 151º19.630'E, 71–77 m deep), heigth 29.8 mm, width 10.7 mm, ventral view (D) and x-ray (E). F. Benthofascis biconica (AMS C.468235, same locality data as above), height 17.9 mm, width 7.7 mm. G–H. Holotype of Benthofascis sarcinula (AMS C.19871, 203 m deep, 20 km miles E of Cape Byron, New South Wales, Australia), height 7 mm, width 4 mm, ventral view (G) and an enlargement of the spire (H). I–K. Benthofascis sarcinula (USNM 902892, SSE of Lakes Entrance, Gippsland Lakes, Victoria, Australia), height 16.6 mm, width 7.4 mm, ventral (I) and lateral views (J) with an enlargement of the spire (K). L–N. Benthofascis sarcinula (USNM 902893, Victoria, Australia), height 24.6 mm, width 10.7 mm, ventral (L) and lateral (M) views and an x-ray (N). Scale bars represent 1 mm.

FIGURE 2. A–D. Holotype of Benthofascis angularis new species (MNHN 23067, 30 m deep, off Cape le Grande, Esperance, southwest Western Australia), height 27 mm, width 11.1 mm, ventral (A) and lateral (B) views with enlargement of spire (C) and an x-ray (D). E, F. Holotype of Benthofascis pseudobiconica new species (MNHN 23069, off Cape Moreton, Queensland, Australia), height 39.8mm, width 12.8 mm, ventral (E) and lateral (F) views. G.Paratype of Benthofascis pseudobiconica new species (ANSP 424978, 183 m deep, off Cape Moreton, S. Queensland, Australia), height 35.3 mm, width 11.8 mm, ventral view. H–K. Paratype of Benthofascis pseudobiconica new species (USNM 902891, South Australia, Australia) height 36.4 mm, width 12.4 mm, ventral (H) and lateral (I) views with an enlargement of the spire (J) and an x-ray (K). Scale bars represent 1 mm.

FIGURE 4. A, B. Radular teeth extracted from Benthofascis biconica (AMS C.468232, shell length of 15.5 mm), photomicrograph (A) and drawing (B) showing internal structures. C, D. Radular teeth extracted from Benthofascis biconica (AMS C.468234, shell length of 15.2 mm), photomicrograph (C) and drawing (D) showing internal structures. E, F. Radular teeth extracted from Benthofascis pseudobiconica (AMS C.373099, shell length of 17.3 mm), photomicrograph (E) and drawing (F) showing internal structures. Scale bar represents 0.1 mm for A–F. G. G. Electron micrographic study of the radular tooth of Benthofascis lozoueti Sysoev & Bouchet, 2001, (MNHN IM200742331, 496 m deep, Norfolk Ridge, 22º50'S, 167º16'E, height 16.4 mm, width 7.0 mm, teeth from the same specimen shown in Fig. 3H). Scale bar dimensions are explained in the figure.