Hortia spenceri, Kantor, Yuri, Lozouet, Pierre, Puillandre, Nicolas & Bouchet, Philippe, 2014

Kantor, Yuri, Lozouet, Pierre, Puillandre, Nicolas & Bouchet, Philippe, 2014, Lost and found: The Eocene family Pyramimitridae (Neogastropoda) discovered in the Recent fauna of the Indo-Pacific, Zootaxa 3754 (3), pp. 239-276 : 261-262

Hortia spenceri new species

Figures 2 L, 12E – F, 13

Turridae sp. 77— Spencer et al. 2009: 211.

Type material. Holotype NMNZ M. 060375; paratype MNHN IM- 2012-2524.

Type locality. New Zealand, South Island, SE of Cape Campbell, 41º55.80’S, 174º40.70’E, 434– 446 m.

Material examined. New Zealand. South Island, SE of Cape Campbell, 41º55.80’S, 174º40.70’E, 434–446 m, R/V Tangaroa , 14.01.1979, 1 lv (holotype NMNZ M. 060375), 1 dd NMNZ M. 310255); North Island, off Gable End Foreland, 38º38.70’S, 178º41.10’E, 725–755 m, R/V Tangaroa , 21.01.1981, 2 dd (paratype MNHN IM- 2012- 2524; NMNZ M.307865); North Island, SE of Aldermen Islands, 37º00.80’S, 176º12.30’E, 178–248 m, R/V Tangaroa , 23.01.1979, 6 dd ( NMNZ M.066713).

Description (holotype) ( Fig. 13 A–D). Shell small, narrow elongate-fusiform, with high elevated spire (LWL/ SL 0.53) and attenuated long canal, consisting of slightly over 1.5 protoconch whorls and 6.25 convex, angulated, teleoconch whorls. Protoconch ( Fig. 13 D) paucispiral, semitransparent, globose, smooth, diameter 730 Μm, height 600 Μm, transition to teleoconch weakly demarcated by the onset of spiral cords. Suture impressed. Besides inconspicuous commarginal growth lines forming a deep broad anal sinus with its tip on whorl periphery, axial sculpture consisting of narrow, closely spaced, strongly sinuous, ribs of the same shape as growth lines, 14 on penultimate and 15 on last whorl, running from suture to suture on spire whorls although rather low above periphery, becoming obsolete on shell base at transition to canal. Spiral sculpture consisting of sharp spiral cords, increasing in number from two on adapical teleoconch whorls to 4 on last whorl, peripheral one forming a strong keel giving teleoconch whorls an angular profile, cords below periphery stronger—one on first two whorls and two on subsequent ones including penultimate whorl; on last whorl, in addition to two strong cords near periphery, five weaker, broadly spaced, cords on shell base, and ten, still narrower and closely spaced, indistinct, ones on canal. Axial ribs forming beads at intersections with spiral cords, most pronounced on peripheral cord and abapical two adjacent ones. Aperture low, narrow elongate, 0.41 (together with canal) of SL. Outer lip partly chipped, concave at transition to long and narrow, nearly straight, canal. Columella short, nearly straight, smooth. Callus narrow, of thin transparent glaze overlying parietal region. Siphonal notch absent. Canal well differentiated from aperture, recurved abaxially. Shell colour off-white. Periostracum tightly adhering, transparent, yellowish.

Measurements (holotype, the largest specimen). SL 9.0 mm, LWL 4.8 mm, AL (with canal) 3.7 mm, SW 3.0 mm.

Radula of holotype ( Fig. 12 E–F) short, about 440 Μm long (11.9% of AL), consisting of about 50 rows of teeth, 5–6 nascent, with strong alary processes embracing the anterior part of the odontophore. Rachidian with broad base strongly arched anteriorly and large cusp. There are numerous, but distinct, additional denticles on both side of major cusp of the rachidian (7–8 on each side), varying from row to row. Sometimes short denticles are present even on tooth basal plate. Lateral teeth high triangular, slightly scoop-shaped, attached by rather narrow base. Inner side adjoining rachidian with several irregularly spaced additional cusps, varying from row to row.

Distribution. New Zealand, off South and North Islands, alive in 434–446 m, shells in 248– 725 m.

Etymology. The specific epithet honors Hamish Spencer, University of Otago, New Zealand, who, among other merits, coordinates the online "Checklist of the Recent Mollusca recorded from the New Zealand Exclusive Economic Zone" (http://www.molluscs.otago.ac.nz/index.html).

Remarks. There is some variation in the degree of development of spiral cords below periphery. In most specimens except the holotype, the one or two cords below periphery are similar in strength to the peripheral cord and as a consequence the whorl outline is less angulated ( Fig. 13 E–F).

Relative to species outside New Zealand, Hortia spenceri differs by its much deeper anal sinus, which is producing the general turriform appearance. Hortia spenceri also differs from H. marshalli in having fewer and more pronounced spiral cords. The radula also sets this new species apart in the much more pronounced additional denticles on the rachidian teeth, even more so than in H. paradrillia .

Figures

FIGURE 2. Overview of fossil and Recent Pyramimitridae. A. Endiatoma quadricincta (Cossmann, 1883), MNHN. F. A 47757, Lower Eocene, France. B – C. Pyramimitra terebraeformis (Conrad, 1848), MNHN. F. J 08748, Middle Eocene, USA. D – E. Pyramimitra quadralirata Dockery, 1977, MNHN. F. A 47750, Middle Eocene, USA. F. Hortia priabonica n. sp., MNHN. F. A 47752, Upper Eocene, France. G. Hortia arriuensis Lozouet, 1999, MNHN. F. A 47751, Upper Oligocene, France. H. Hortia pseudotaranis n. sp., New Caledonia, SL 8.4 mm. I. Hortia macrocephala n. sp., New Caledonia, SL 10.4 mm. J. Hortia paradrillia n. sp., New Caledonia, SL 8.1 mm. K. Hortia marshalli n. sp., New Zealand, SL 10.6 mm. L. Hortia spenceri n. sp., New Zealand, SL 9.0 mm. M. Hortia aotearoa n. sp., New Zealand, SL 9.0 mm. N. Hortia solitaria n. sp., South of Madagascar, SL 6.5 mm. O. Teremitra fallax n. sp., Solomon Islands, SL 11.8 mm. P. Teremitra efatensis (Aubry, 1999), Vanuatu, SL 10.8 mm. Q. Teremitra? hortensis (Vinassa de Regny, 1898), Upper Eocene, France. R. Teremitra sp., Taiwan, SL 16 mm. S. Vaughanites? superstes n. sp., Philippines, SL 19.1 mm.

FIGURE 12. Radulae of Recent Hortia species. A – D. Hortia marshalli n. sp. A. Dorsal view of the central part of the radular membrane of paratype (MNHN IM- 2012 - 2525, shell on 11 F – G). B. Same, enlarged anteriormost part of radular membrane. C – D. Northern Bounty Trough (NMNZ M. 307883, shell on 11 L). C. Dorsal view of the central part of the radular membrane, D. Enlarged central and right lateral teeth. E – F. Hortia spenceri n. sp., holotype. E. Dorsal view of the central part of the radular membrane. F. Enlarged central and right lateral teeth.

FIGURE 13. Hortia spenceri n. sp. A – D. Holotype, SL 9. 0 mm (D—enlarged protoconch). E. Paratype, SL 8.3 mm, MNHN IM- 2012 - 2524. F. North Island, SE of Aldermen Islands (NMNZ M. 066713), SL 6.7 mm. All shells at the same scale.