Clavator griffithsjonesi Emberton, 1999

Griffiths, O. L. & Herbert, D. G., 2013, New species of land snails (Mollusca: Gastropoda) from two isolated karst formations in central western Madagascar: Tsingy Beanka and Antsingimavo, with additional notes on other regional endemics, African Invertebrates 54 (1), pp. 1-48 : 16-18

Clavator griffithsjonesi Emberton, 1999

Figs 11 , 25D

Clavator griffithsjonesi: Emberton 1999: 93 , figs 13, 14. Type loc.: Madagascar: N Bemaraha Reserve (18°1'S 44°31'E) [= the area now known as Tsingy Beanka].

Morphological notes:

External features ( Fig. 25D ): Head-foot mostly greyish cream with pedal margin tinged orange-brown; dorso-lateral areas of neck yellowish, mid-dorsal region greyish; distal half of optic tentacles grey.

Distal genitalia ( Fig. 11 ): Penis slender and cylindrical, with relatively muscular wall; apical ⅔ comprising a blind ending caecum, above insertion of epiphallus; retractor muscle inserted at apex of caecum; interior of penis with approx. 6 well-developed, longitudinal pilasters; epiphallus somewhat recurved at its insertion, opening into a deep cleft in one pilaster, near to base of penis; pilasters dividing and anastomosing somewhat in caecum. Epiphallus extremely long and convoluted, its convolutions and those of vas deferens enveloped in membranous covering of connective tissue and attached to lower spermoviduct and free oviduct; a short flagellum present at junction of vas deferens and epiphallus; interior wall of epiphallus with one large longitudinal pilaster and 6 or 7 smaller longitudinal ridges, these continue into flagellum, evanescing near its tip; vas deferens discharges into epiphallus via a pore situated on large pilaster; vas deferens passing over and down lower sperm-oviduct to its origin at base of prostate; lumen of vas deferens for the most part simple, but broadening just prior to junction with epiphallus, and inner wall with 3 longitudinal folds each with side branches. Genital atrium short and simple; bursa copulatrix duct arising after a short vagina; duct very long, of more or less even width, its wall relatively sturdy; bursa copulatrix situated just below level of albumen gland, bean-shaped with a slightly pointed apex; bursa and its duct brownish in colour. Free oviduct short.

Locality data: Tsingy Beanka : st’ns 11/06, 12/06, 15/06 (subfossil), 16/06, 18/06, 06/09, 07/09, 08/09 (subfossil and fresh), 09/09.

Distribution: Evidently a narrow-range endemic; not found in either the Tsingy de Bemaraha or at Antsingimavo, and currently known to occur only in the Tsingy Beanka .

Habitat: Mostly found in tall deciduous forest growing on limestone in the southern areas of Tsingy Beanka ; less common as one moves north. Buries shallowly in leaf-litter during the dry season.

Remarks: A characteristic element of the Tsingy Beanka malacofauna and the only species of Clavator recorded from central western Madagascar.

The distal genitalia closely resemble those figured by Schileyko (1999) for C. eximius (Shuttleworth, 1852) . Fischer-Piette et al. (1975) illustrated the genitalia of two further Clavator species, of these C. clavator (Petit de la Saussaye, 1844) is similar to C. griffithsjonesi , but it has a more slender bursa copulatrix duct. These authors did not differentiate between an epiphallus and vas deferens in C. clavator , neither did they report a flagellum at the junction of the epiphallus and vas deferens, but this may have been overlooked. C. moreleti (Deshayes, 1851) differs considerably in having a much shorter epiphallus/vas deferens that inserts just below the apex of the penis. It also has a shorter, very slender bursa copulatrix duct.

Figures

Fig. 11. Clavator griffithsjonesi Emberton, 1999, genitalia, NMSA L7236: (A) entire reproductive tract (minus ovotestis); (B) penis opened longitudinally to show internal folds and pore at insertion of epiphallus.Abbreviations: ag – albumen gland, bc – bursa copulatrix, bcd – bursa copulatrix duct, ep – epiphallus, epp – epiphallus pore, f – flagellum, ga – genital atrium, hd – hermaphrodite duct, p – penis, pf – folds lining penis lumen, prm – penial retractor muscle, sod – spermoviduct, v – vagina, vd – vas deferens.

Fig. 25. Living animals from Tsingy Beanka: (A) Acroptychia bathiei Fischer-Piette & Bedoucha, 1965, st’n 13/06, shell diameter 23.2 mm, NMSA L7315; (B) Tropidophora humbug sp. n., st’n 12/06, shell diameter 28.3 mm, paratype,NMSA L7204/T2984; (C) Tropidophora secunda Fischer-Piette & Bedoucha, 1965, st’n 03/06, shell diameter approx.19.0 mm; (D) Clavator griffithsjonesi Emberton, 1999, st’n 12/06, shell height 94.8 mm, NMSA L7192; (E) Ampelita milloti Fischer-Piette,1952,st’n 07/09, shell diameter 19.2 mm, NMSA L8502; (F) Ampelita namerokoensis Fischer-Piette, 1952, st’n 12/06, shell diameter 20.3 mm, NMSA L8442; (G) Kalidos griffithshauchleri Emberton, 2002, st’n 12/06, shell diameter approx. 60 mm; (H) Kalidos maryannae sp. n., st’n 12/06, shell diameter 22.5 mm, paratype, NMSA L7193/T2944.