Favartia (Pygmaepterys), Vokes, 1978

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 : 516-518

Subgenus Pygmaepterys Vokes, 1978

TYPE SPECIES. — Murex alfredensis Bartsch, 1915 , South Africa (by original designation).

Favartia (Pygmaepterys) fournierae n. sp. ( Figs 1E ; 3D, E ; 6 B-E; 7I, J)

TYPE MATERIAL. — Holotype MNHN 26518 and 7 paratypes MNHN 26518-26521 , 1 paratype RH.

TYPE LOCALITY. — South Madagascar, West of Pointe Evatra, 24°59.2’S, 47°05.4’E, 2-7 m ( ATIMO VATAE: stn TB08).

MATERIAL EXAMINED. — ATIMO VATAE: stn TB08, Ouest Pointe Evatra, 24°59.2’S, 47°05.4’E, 2-7 m, 1 lv (holotype MNHN 26518 = IM-2009- 14264). — Stn DW3519, entre Lokaro et Ste Luce,

24°51.9’S, 47°28.0’E, 80-83 m, 2 lv (1 paratype MNHN 26519, 1 paratype RH). — Stn DW3532, Nord de Sainte Luce, 24°39.4’S, 47°31.7’E, 86-87 m, 1 dd. — Stn CP3603, SW Cap Sainte Marie, 25°57.1’S, 44°47.6’E, 62-63 m, 1 dd. — Stn DW3605, SW Cap Sainte Marie, 24°54.5’S, 44°51.0’E, 56-57 m, 3 dd ad & juv (paratypes MNHN 26520). — Stn DW3606, SW Cap Sainte Marie, 25°48.4’S, 44°51.1’E, 44-46 m, 3 lv & dd, ad & juv (paratypes MNHN 26521). — Stn DW3607, SW Cap Sainte Marie, 25°45.7’S, 44°52.0’E, 40-41 m, 1 dd, juv.

DISTRIBUTION. — South Madagascar, live in 7-80 m, shells in 41- 86 m.

ETYMOLOGY. — At the request of Philippe Bouchet, this species is named after Laure Fournier, coordinator of marine biodiversity programmes at theTotal Foundation. The Foundation has supported many MNHN expeditions since 2000, and was the main sponsor of the ATIMO VATAE expedition.

DESCRIPTION

Shell large for the subgenus, up to 8.4 mm in height at maturity. Height/width ratio 1.6-1.9. Biconical, broadly ovate, nodose and squamous. Subsutural ramp narrow, weakly sloping, weakly concave. Greyish white, light tan or reddish brown. Aperture similarly coloured. Protoconch milky white.

Spire high with 1.65-1.75 protoconch whorls and teleoconch up to 4.15 broad, angular, strongly shouldered, nodose whorls. Suture impressed. Protoconch small, whorls rounded, last part of last whorl minutely striate and punctuate; maximum width 650-750 µm, height 600 µm. Terminal lip delicate, thin, weakly raised and weakly curved.

Axial sculpture of teleoconch whorls consisting of relatively strong, narrow, frondose varices. Other axial sculpture of low, flattened, broad growth lamellae or scales. First whorl with five or six varices, second with three to five varices, penultimate and last whorls with three varices. Spiral sculpture of high and low, weak and strong, rounded, squamous, primary and secondary cords. First whorl with low P1 and high P2, second whorl with P1- P3, P2 broadest and highest, P3 partially covered by following whorl, third whorl with additional, occasional, narrow, low IP, fourth and last whorls with (IP), P1, P2, (s2), P3, P4, P5, (s5), P6, ADP, (MP). Spiral cords joined by low, flattened, broad growth lamellae or scales. IP, when present, very narrow, low, P1 broad, low, P2 broadest, high, s2, when present, narrow, rounded, P3 rounded or flat, P4-MP more conspicuous on varices, flat between varices, occasionally flat on varices.

Aperture moderately large, ovate. Columellar lip narrow, smooth, rim partially erect, adherent at adapical extremity. Anal notch shallow, broad. Outer lip weakly crenulated, smooth within or with very weak, low, elongate denticles. Siphonal canal short, narrow, strongly dorsally recurved at tip, narrowly open.

Operculum and radula unknown.

REMARKS

Three Pygmaepterys species are known from the studied area or nearby localities: F. (P.) alfredensis (Bartsch, 1915) , the type species,from Port Alfred, South Africa, F. (P.) isabelae Houart& Rosado,2008 from Madagascar and Mozambique and F. (P.) maraisi (Vokes,1978) from northernTranskei, South Africa.None of these species has a shell with three axial varices on the penultimate and last teleoconch whorls and they do not need to be compared here. F. (P.) alfredensis and F. (P.) isabelae have five narrow varices while F. (P.) maraisi has six to eight varices on the last teleoconch whorl.

The Pygmaepterys species with three varices on the last teleoconch whorl are F. (P.) cracentis (Houart, 1996) from Indonesia, F. (P.) dondani (Kosuge, 1984) from the Philippines and F. (P.) menoui (Houart, 1990) from New Caledonia.

Favartia (P.) dondani is a very different, larger species and does not need to be compared here.

Favartia (Pygmaepterys) cracentis ( Fig. 6F ) has a much narrower shell with more numerous axial varices on spire whorls: first and second whorl with seven ribs, third with six, penultimate with four or five and only the last whorl has three varices. The primary and secondary spiral cords are also more numerous than in F. (P.) fournierae n. sp. and more regularly shaped with primary and secondary cords of almost similar size, with a total of 11 or 12 cords on the last teleoconch whorl.

Favartia (Pygmaepterys) menoui ( Fig. 6G, H ) is the most similar species, but it differs in having three varices only from the fourth teleoconch whorl instead of the second or third in F. (P.) fournierae n. sp., in having a different spiral sculpture morphology with broadly spaced P1 and P2 with an additional s1 between them, followed by a broad P3 and narrower P4, then s4, P5, P6, MP and ADP, and in having a comparatively smaller and narrower aperture.

The spiral cord morphology in F. (P.) fournierae n. sp., particularly the higher and broader second spiral cord (P2) as well as the axial, flattened growth lamellae or scales are reminiscent of Pterynotus concavopterus Kosuge, 1980 from the Philippines, a species that was doubtfully included in Timbellus de Gregorio, 1885 by Merle et al. (2011). The similarities between P. concavopterus and F. (P.) fournierae n. sp. and other Pygmaepterys species are intriguing. The shell morphology of P.concavopterus is certainly more similar to muricopsine species than to any Pterynotus Swainson, 1833 or Timbellus species. Molecular analyses and study of the radula are needed to confirm the probable new classification of this species, till now only known from the Philippines.

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.