Semiricinula bozzettii, Houart & Héros, 2013

Houart, Roland & Héros, Virginie, 2013, Description of new Muricidae (Mollusca: Gastropoda) collected during the ATIMO VATAE expedition to Madagascar “ Deep South ”, Zoosystema 35 (4), pp. 503-523 : 518-521

Semiricinula bozzettii n. sp.

( Figs 1F ; 3C ; 6 I-N; 7K, L; 8C-E)

TYPE MATERIAL. — Holotype MNHN 26522 , 11 paratypes MNHN 26523-26528 , 3 RH.

A

C

E

TYPE LOCALITY. — South Madagascar, Îlot de Lokaro, 24°56.5’S, 47°07.1’E, 0-1 m ( ATIMO VATAE: stn TM 05).

MATERIAL EXAMINED. — ATIMO VATAE: stn BM 01, Plage de Lavanono, 25°25.2’S, 44°56.3’E, 0-1 m, 1 lv (paratype MNHN 26524 = IM-2009-14735). — Stn TM 02, Cap Ranavalona, 25°04.3’S, 46°57.7’E, 0-1 m, 1 lv, juv. — Stn TM 03, Cap Ranavalona, 25°04.5’S, 46°57.7’E, 0-1 m, 1 lv, juv.— Stn BS05, Cap Sainte Marie, 25°35.4’S, 45°08.0’E, 12 m, 1 lv (IM-2009-22459 BOLD ID BOMGA 012-13, GenBank accession number for COI gene KC 860509 ).— Stn TM 05,Îlot de Lokaro, 24°56.5’S, 47°07.1’E, 0-1 m, 2 lv (holotype MNHN 26522 se - quenced as IM-2009-22436 BOLD ID BOMGA 008-13, GenBank accession number for COI gene KC 860510 ), paratype MNHN 26523 sequenced as IM-2009-22490 BOLD ID BOMGA 001-13, GenBank accession number for COI gene KC 860508 ). — Stn BM 07, Est du Cap Malaimpioka, 25°21.5’S, 44°50.0’E, 0-1 m, 1 lv (paratype MNHN 26525). — Stn TS11, Cap Ranavalona, Bevava, 25°04.4’S, 46°57.1’E, 4-5 m, 1 dd, juv. — Stn BS12, Rocher de l’Albatros, 25°28.6’S, 44°56.8’E, 12 m, 2 dd, juv. — Stn TP15, Baie de Fort-Dauphin, 25°00.06’S, 47°00.0’E, 16-18 m, 1 lv (IM-2009-22447 BOLD ID BOMGA 013-13, GenBank accession number for COI gene KC 860512 ) — Stn BV16, devant Lavanono, 25°25.6’S, 44°55.9’E, 9 m, 1 lv. — Stn TM 19, Sainte Luce, 24°47.1’S, 47°11.9’E, 0-1 m, 3 lv (paratypes MNHN 26526). — Stn TP19, devant plage d’Ambinanibe, 25°04.4-7’S, 46°55.3-56.3’E, 19-26 m, 1 dd. — Stn TS20, “entrée “Lac” de Mananivo, 24°56.0’S, 47°06.7’E, 3 m, 1 lv. — Stn TM 21, Baie des Galions, 25°08.9’S, 46°45.4’E, 0-1 m, 6 lv (3 paratypes MNHN 26527, 3 paratypes RH). — Stn TP21, Fausse Baie des Galions, 25°03.3’S, 46°59.1’E, 23-25 m, 1 dd, juv. — Stn BP23, secteur de Lavanono, 25°26.4-8’S, 44°56.1-3’E, 6-9 m, 1 lv (IM-2009-22466 BOLD ID BOMGA 003-13, GenBank accession number for COI gene KC 860511 ) and 3 dd. — Stn BP24, secteur de Lavanono, 25°27.1’S, 44°56.2’E, 13 m, 2 lv (paratypes MNHN 26528). — Stn BP33, secteur de Lavanono, 25°25.80-8’S, 44°55.7-8’E, 11-13 m, 1 dd. — Stn TA 59, Baie des Galions, 25°09.1’S, 46°45.4’E (no other data), 1 dd.

DISTRIBUTION. — South Madagascar, live in 0-1 m, intertidal, shells in 5- 23 m.

ETYMOLOGY. — The species is named after Luigi Bozzetti, of Milano, the pioneer of molluscan exploration in southern Madagascar, and author of many new species, including of Muricidae . Luigi joined the ATIMO VATAE expedition field party in Fort-Dauphin.

DESCRIPTION

Shell small for the genus, up to 17.4 mm in height at maturity (paratype MNHN). Height/width ratio 1.7-1.9. Lanceolate, narrowly-ovate, nodose and squamous, lightly built. Subsutural ramp broad, strongly sloping and strongly concave.

Light tan, dark tan or greyish with dark brown blotches on nodes of primary spiral cords, some light brown blotches on secondary cords. Shell lighter coloured between primary spiral cords. Columellar lip greyish or yellowish brown, dark brown on and between columellar folds. Inner side of outer lip light brown, dark brown between apertural denticles.

Spire high with 1.75 protoconch whorls. Teleoconch up to five convex, weakly angular, strongly shouldered, squamous whorls. Suture adpressed, partially obscured by small axial lamellae of next whorl.Protoconch moderately large, whorls rounded, smooth; maximum width 800 µm, height 900 µm. Terminal lip narrow, almost straight.

Axial sculpture of teleoconch whorls consisting of very low, broad, rounded ribs, narrower on two first teleoconch whorls. Other axial sculpture of numerous, high, thin, growth lamellae. First and second whorls with 13 ribs, third with 11 or 12 ribs, fourth with 10, last with 9 ribs. Spiral sculpture of high, strong, rounded, narrow, nodose primary and secondary cords and lower, narrower, squamous threads. First teleoconch whorl with SP, IP, P1, s1, (P2). P2 covered partially or completely by next whorl, second whorl with SP, IP, P1, (t), s1, P2, third whorl of a juvenile specimen with SP, adis, IP, abis, P1 split, t, s1, t2, P2, s2, t, P3, s3, P4, s4, P5, P6, fourth whorl of a juvenile with SP, adis, IP, abis, P1 split, t, s1, P2, s2, P3, s3, P4, s4, P5, P6. Last whorl with SP, t, adis, IP, abis, P1 split, t, s1, t, P2, t, s2, t, P3, t, s3, t, P4, s4, P5, (s5), P6, (s6), and occasional fine threads between secondary and primary spiral cords. Crossing of axial ribs and primary spiral cords giving rise to broad, moderately high nodes. Crossing of axial growth lamellae with secondary cords and threads giving a reticulate appearance to the shell.

Aperture moderately large, ovate. Columellar lip narrow, with two elongate, weak, oblique folds centrally, rim completely adherent, broadly expanded abapically. Occasionally with weak parietal tooth at adapical extremity. Anal notch deep, narrow. Outer lip weakly erect, thin, with weak or very weak, elongate denticles within: D1 split, D2 split, D3, D4, D5 ( Fig. 6N ). Denticles increasing in strength up to D4; D5 very shallow, almost indistinguishable. Siphonal canal very short, broad, straight, broadly open.

Operculum light brown, thin, D-shaped, tapered adapically, with lateral nucleus in lower right. Attached surface with few growth lines and broad, thin, callused rim.

Radula ( Fig. 8 C-E) with a broad, long, elongate, central cusp, a twice shorter, broad, lateral cusp on each side with a short inner and outer lateral denticle on its base, two or three short marginal denticles and a broad, moderately high marginal cusp. Lateral tooth sickle shaped, narrow, with a broader base.

REMARKS

The new species described here is included in Semiricinula because of the similar radular and operculum morphologies but also because of identical shell morphologies, especially the squamous shell structure, the typical, deep anal notch, and the two narrow columellar folds.The radula of S. turbinoides is illustrated ( Fig. 8F ) to show the similarities between the two species.

Semiricinula bozzettii n. sp. differs from S. turbinoides ( Fig. 7E ) in having a lighter, more delicate shell with more numerous axial ribs, nine or ten on penultimate and last whorls vs seven in S. turbinoides , much narrower primary spiral cords, split apertural denticles and chiefly, in having a very different protoconch of 1.75 rounded whorls ( Fig. 7K, L ) vs 2.5-3 whorls with a duplicate narrow keel on the last whorl in S. turbinoides . The protoconch also lacks a sinusigeral notch ( Fig. 7M ).

The status of Thais tricolorata Bozzetti, 2010 will be discussed in an upcoming paper in progress. However, S. bozzettii n. sp. differs from T. tricolorata in the same ways that it differs from S. turbinoides .

Semiricinula bozzettii n. sp. can also be compared with S. muricoides (Blainville, 1832) ( Fig. 7C, D ), which has not been recorded from Madagascar and which also has a paucispiral protoconch of 1.75 to 2 rounded whorls. However, S. bozzettii n. sp. differs from S. muricoides in having a smaller, more delicate shell with much narrower primary spiral cords, a narrower anal notch, split apertural denticles and more numerous axial ribs.

Because of its reticulate shell morphology, Semiricinula bozzettii n. sp. could also be considered as a Phycothais Tan, 2003 species. Phycothais was originally described by Tan (2003: 956) to include two intertidal Australian species: P. reticulata (Quoy & Gaimard, 1832) , which occurs from New South Wales to Western Australia, including Tasmania, and P.botanica (Hedley, 1918) , known from Queensland to Tasmania. The shells are small, less than 20 mm in length with a paucispiral protoconch and a typical rapanine radula.

A third species of Phycothais , P. texturata (E. A.Smith, 1904) was recently recorded by Houart et al. (2011).

The shells also have a typical reticulate or cancellate sculpture due to the numerous axial growth lamellae, more obvious between than on the spiral cords.

Semiricinula bozzettii n. sp. is similar to P.reticulata ( Fig. 7B ) but differs in having a slightly narrower shell with a relatively higher spire, a different, narrower and deeper anal notch, a more obvious parietal tooth, and a folded columella, which is smooth in P. reticulata . It differs also from P. botanica ( Fig. 7A ) in having a higher spire, a slightly less shouldered shell, a different, narrower and deeper anal notch, a folded columellar lip and also in having somewhat narrower primary spiral cords.

Finally, Semiricinula bozzettii n. sp. differs in shell characters from P. texturata in the same way that it differs from P.reticulata but also in having secondary and tertiary cords of similar strength in P. texturata vs of different strength in S. bozzettii n. sp.

The holotype is not the best specimen, but it has been chosen as the name-bearing type because it is associated with a molecular sequence

Figures

FIG. 1. — Distribution of the six new species described herein: A, Chicoreus (Triplex) kantori n. sp.; B, Naquetia manwaii n. sp.; C, Dermomurex (Dermomurex) charlesi n. sp.; D, Favartia (Favartia) tantelyi n. sp.;E, Favartia (Pygmaepterys) fournierae n. sp.; F, Semiricinula bozzettii n. sp. Symbols: Ê, type locality; £, other occurences.

FIG. 3. — Spiral cords morphology: A, Chicoreus (Triplex) kantori n. sp. (holotype), 19.1 mm; B, Naquetia manwaii n. sp. (holotype), 34 mm; C, Semiricinula bozzettii n. sp. (holotype), 16 mm; D, E, Favartia (Pygmaepterys) fournierae n. sp.; D, Holotype, 10.2 mm; E, Paratype MNHN 26519, 8.4 mm. Abbreviations: see Material and methods.

FIG. 6.— A, Favartia (F.) confusa (Brazier,1877),holotype AMS C077183,26.8 mm (scan of a white and black photograph);B-E, Favartia (Pygmaepterys) fournierae n.sp.; B, C, holotype MNHN 26518,10.2 mm;D, E, paratype MNHN 26519,8.4 mm;F, Favartia (Pygmaepterys) cracentis (Houart,1996),holotype RMNH 57153,11.8 mm (scan of black and white photograph); G, H, Favartia (Pygmaepterys) menoui (Houart, 1990), eastern New Caledonia, holotype MNHN 0193, 7 mm; I-N, Semiricinula bozzettii n. sp.; I, J, paratype MNHN 26524, 16 mm; K, paratype MNHN 26528, 17.2 mm; L, M, holotype MNHN 26522, 10.3 mm; N, apertural denticles, paratype MNHN 26525. Abbreviations: see Material and methods. Scale bar: N, 2 mm.

FIG. 8. — Radulae; A, B, Naquetia manwaii n. sp., holotype MNHN 26506,A, Scale bar:100 µm; B, Scale bar:10 µm; C-E, Semiricinula bozzettii n. sp.; C, paratype MNHN 26527, Scale bar: 50 µm; D, E, paratype MNHN 26526; D, Scale bar: 50 µm; E, Scale bar: 10 µm; F, Semiricinula turbinoides (Blainville, 1832), Balicasag, Philippines, RH, Scale bar: 60 µm.

FIG. 7. — A, Phycothais botanica (Hedley,1918),Australia,North NSW,Hastings Point, 12.4 mm, RH; B, Phycothais reticulata (Quoy & Gaimard,1832), Australia,Western Port, 16.8 mm,syntype MNHN 0927;C, D, Semiricinula muricoides (Blainville,1832), New Zealand (erroneous), 23.4 mm, syntype MNHN 0163; E, Semiricinula turbinoides (Blainville, 1832), New Caledonia, 17.4 mm, RH; F-M, Protoconchs; F, Chicoreus (Triplex) kantori n. sp. (holotype), Scale bar: 500 µm; G, Naquetia manwaii n. sp. (holotype), Scale bar: 500 µm; H, Dermomurex (Dermomurex) charlesi n. sp.paratype MNHN 26514,Scale bar:500 µm;I, J, Favartia (Pygmaepterys) fournierae n. sp.; I, paratype MNHN 26520, Scale bar: 500 µm; J, paratype MNHN 26520, Scale bar: 100 µm; K, L, Semiricinula bozzettii n. sp. (ATIMO VATAE: stn BS12, MNHN), Scale bar: 500 µm; M, Semiricinula turbinoides (New Caledonia, RH), Scale bar: 500 µm.