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 Author Griffiths, O. L. Research associate of the Australian Museum, Sydney, Australia and Biodiversity Conservation Madagascar (BCM) Ltd, Rivière des Anguilles, Mauritius owen@bcm.intnet.mu Author Herbert, D. G. KwaZulu-Natal Museum, P. Bag 9070, Pietermaritzburg, 3200 South Africa and School of Life Sciences, University of KwaZulu-Natal, Pietermaritzburg, 3206 South Africa dherbert@nmsa.org.za text African Invertebrates 2013 2013-02-13 54 1 1 48 journal article 54828 10.5733/afin.054.0101 753510a6-cffa-4637-a1bd-e9ae7d5d1660 2305-2562 7670100 3795B466-1227-4BED-AD8A-DC88CA3E14E1 Ampelita namerokoensis Fischer-Piette, 1952 Figs 17E, 17F , 19 , 20 , 25F Ampelita namerokoensis : Fischer-Piette 1952: 35 , pl. 3, figs 35–39; Fischer-Piette et al . 1994: 123, pl. 15, figs 5–8. Type loc.: ‘ Gorges de Salapango [= Salapanga], Bemaraha’, Madagascar . Morphological notes: External features ( Fig. 25F ): Head-foot mostly dark grey-brown with uniformly granular skin texture; optic tentacles slightly paler, running into similarly pale bands along neck; skin granules with microscopic ochre-brown pigment granules; lining of mantle cavity with some black pigmentation (not dense) and a pattern of pale circular blotches. Distal genitalia ( Fig. 20 ): Resembling those of A. beanka , but differing considerably in penis morphology, particularly its internal structure. Penis shorter ( ca 3.2 mm ) and more slender than in A. beanka , and the apical region less swollen; vas deferens follows a similar path alongside penis, running to its apex and then recurving before inserting subterminally via a short, somewhat broader, pale flesh-coloured epiphallus; details of recurved vas deferens and epiphallus mostly concealed by attachment of retractor muscle. Interior of penis with a small conical papilla at insertion of epiphallus, from which a single mid-line fold runs to penis base; additional concentric folds surround papilla on both sides, these converging and evanescing toward penis base; the resultant pattern of folds differing considerably from that of A. beanka . Fig. 19. Ampelita namerokoensis Fischer-Piette, 1952 : (A–C) typical specimen, Tsingy Beanka , st’n 07/09, max. diameter 22.1 mm, NMSA L8445; (D) depressed specimen, Tsingy Beanka , st’n 12/06, max. diameter 23.1 mm, NMSA L8440. Locality data: Tsingy Beanka : st’ns 03/06, 11/06, 12/06, 14/06, 16/06, 18/06, 02/09, 06/09, 07/09, 08/09, 09/09, 11/09, 01/10, 02/10, 05/10, 07/10, 08/10, 09/10, 10/10. Bemaraha : st’ns 14/95, 09/96, 12/96. Distribution: Restricted to central western Madagascar , with reliable records only from the Tsingy de Bemaraha and Tsingy Beanka ; not found at Antsingimavo and, despite its name, evidently does not occur in Nameroko [Namoroka] (see Remarks below). Habitat: Living specimens are found most commonly amongst limestone rocks and in leaf-litter. In Tsingy Beanka , it occurs mostly in the southern region, in taller, moister forests. Remarks: Shell lenticular, of moderate size (max. diameter < 26 mm , but rarely more than 23 mm ), carinate at periphery; uniformly light brown when fresh, with a pale yellowish band around the umbilicus. Protoconch essentially smooth ( Fig. 17E ), but sometimes with microscopic traces of oblique, close-set striae on last embryonic whorl, forming an extremely fine criss-cross pattern. Teleoconch with fine spiral sculpture ( Fig. 17F ). The choice of name for this species is puzzling since the type locality [Salapanga] is in the Tsingy de Bemaraha. Fischer-Piette (1952) mentioned material from Ambongo (collected by G. Petit and H. Perrier de la Bâthie), which he equated with the ‘Tsingy de Nameroko’. Elsewhere, however, Fischer-Piette and Bedoucha (1965: 62) stated that Salapanga [known to be in the Bemaraha] was also in the Ambongo region, suggesting in this case that Ambongo equates with Bemaraha. In line with this, S. Goodman (pers. comm. 2010), confirmed that Ambongo has been used for both Bemaraha and Namoroka. There is therefore some doubt regarding the occurrence of this species in Namoroka and despite survey work (Griffiths in 1997 and Emberton in 2007), no specimens have been found there. Fig. 20. Ampelita namerokoensis Fischer-Piette, 1952 , genitalia, NMSA L8442: (A) entire reproductive tract; (B) external view of penial complex; (C) penis opened longitudinally to show internal folds and raised papilla at insertion of epiphallus. Abbreviations: ag – albumen gland, bc – bursa copulatrix, bcd – bursa copulatrix duct, ep – epiphallus, ga – genital atrium, hd – hermaphrodite duct, od – oviduct, p – penis, pf – folds lining penis lumen, pp – penis papilla, pr – prostate, prm – penial retractor muscle, v – vagina, vd – vas deferens. Additional material from the Kelifely Plateau (st’ns 06/05, 10/05) resembles this species in having spiral sculpture, but the protoconch is sculptured with distinct axial riblets like that of A. milloti .At this stage its identity remains puzzling. Further subfossil or very old dead specimens from limestone caves in the Anjajavy– Narinda area , northeast of Mahajanga (Griffiths pers. observ.) may also be referable here .