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The terrestrial littorinoid snail genus Tropidophora Troschel, 1847 is especially diverse on Madagascar with 94 currently recognized species and numerous named varieties. Supposed high within-species variation in shell and genital morphology led some researchers to suggest that these characters may be too variable to distinguish species, prompting them to conclude that the group may be taxonomically over-split. Recent sampling allows an independent test using COI sequence data which suggests that Madagascar's Tropidophora species are not over-named but are more diverse than previously thought. Molecular diversity is congruent with traditional morphology-based species concepts suggesting that future work using both molecular and morphological data sets will be useful in a taxonomic revision of the genus.

Survey work carried out in the Mascarene Islands of Reunion, Mauritius and Rodrigues in the S.W Indian Ocean over the last 10 years have yielded at least 14 new species, 9 of which are described here:- Assimineidae: Omphalotropis stevanovitchi; Pomatiasidae: Tropidophora vincentflorensi; Helicarionidae: Ctenophila aigretteianum; Erepta wendystrahmi; Pachystyla waynepagei; Dupontia affouchensis; Streptaxida : Gonospira jacobsi; Gulella mamellensis: Gulella argoudi.

Tropidophora humbug sp. n. Figs 5, 6, 25B Etymology: The colour pattern of bold stripes is reminiscent of that of old-fashioned humbug sweets; used as a noun in apposition. Diagnosis: Spire very low, shell almost planorboid, body whorl not conspicuously tumescent, umbilicus very wide; columella lip not expanded and not reflected over umbilicus; surface virtually smooth to the naked eye; boldly marked with brown spiral bands on a near white ground. Description: Shell: Medium sized, depressed-discoidal to planorboid; spire very low (H:D=0.46– 0.62), often with only embryonic whorls projecting in apertural view; final part of last adult whorl descending prior to aperture, but not steeply so; whorls more or less evenly rounded, suture indented; umbilicus very wide, its margin evenly rounded, underside of embryonic whorls clearly visible. Protoconch of 1¼–1½ whorls, essentially smooth, but microscopically shagreened. Teleoconch of a further 2½–2¾ whorls; the first with approx. 6 weak spiral ridges crossed by numerous fine, close-set, axial threads; spirals becoming more numerous but less distinct on subsequent whorls and axials somewhat coarser; axials resembling fine, uneven, close-set growth-lines on last half-whorl of adult, these extending onto base and into umbilicus; base lacking spiral sculpture. Aperture subcircular, strongly oblique to vertical axis of shell; peristome incomplete, interrupted briefly in parietal region; rim of peristome reflected forming a flaring lip, but this not noticeably enlarged in columella region. Ground colour bone-white, boldly marked with dark brown spiral bands, the one at and extending just below periphery usually broadest, commonly with 2 or 3 additional bands above and a further 2 or 3 below this; an additional fine orange-brown intermediary spiral line sometimes present in intervals between bands; umbilical region with additional colour bands, often fine, such that base may have up to 7 bands in total; exceptionally, base may have only 1 or 2 colour bands; precise position of colour bands somewhat variable, but uppermost band generally not in contact with suture. Dimensions: Holotype, max. diameter 31.5 mm, height 16.3 mm; largest specimen, max. diameter 32.0 mm. External features (Fig. 25B): Head-foot more or less uniformly dark grey-brown, but eyestalks and tentacle bases paler; tip of snout conspicuously indented in mid-line; skin texture finely granular. Operculum (Fig. 5G): Oligospiral; exterior portion a calcareous disc, attached to an inner and slightly larger corneous layer; external surface off-white (usually encrusted with detritus particles), lacking colour pattern, but with a broad convex spiral ridge more or less at mid-whorl; thinner toward periphery; edge of disc concave, with numerous, closeset, rather unevenly spaced transverse partitions, except along the growing (parietal) margin, which is smooth. Radula (Fig. 6): Formula 1+2+1+2+1; length 11 mm, ca 35 rows/mm; dentition fine. Rachidian with seven rounded cusps, central one largest, the outermost pair small; occasionally with very small intermediary teeth between the larger ones. Inner laterals with four cusps, the second of which is bluntly rounded and consistently the largest, the others more pointed; outer lateral with five cusps, the inner one usually slightly larger, the others progressively smaller. Marginal teeth broad, the edge comprising three regions; an inner coarsely dentate element with ca 9 denticles; a more finely denticulate central region, and a smooth outer portion. Such a radula conforms to the pattern seen in Tropidophora (Ligatella) Martens, 1880 (Fischer-Piette et al. 1969). Holotype: MADAGASCAR: Central W Madagascar, ca 60 km E of Maintirano, tall dense dry forest growing above cliffs on E side of southern Tsingy Beanka at Andohanandranogedro, 18.05028°S 44.53786°E, 380m, iv.2009, R. Randalana, st’n R04/09 (AMS C.474165). Paratypes: Same data as holotype (NMSA L8547 /T2962, 2 specimens); st’n 14/95 (AMS C.469588, 5 specimens); st’n 10/96 (AMS C.469587, 5 specimens); st’n 14/96 (AMS C.469589, 2 specimens); st’n 15/96 (NMSA L8444 /T2658, 6 specimens); st’n 03/06 (NMSA L7042 /T2961, 45 specimens, some in alcohol; MNHN IM-2010-20067, 2 specimens; NHMUK 20120013, 2 specimens); st’n 12/06 (NMSA L7204 /T2984, 2 specimens); st’n R04/09 (AMS C.469590, 6 specimens; TMAM T166, 7 specimens); st’n R01/10 (TMAM T160, 5 specimens); st’n R02/10 (MNHN IM-2010-20068, 7 specimens). Additional locality data: Tsingy Beanka: st’ns 05/06, 11/06, 12/06, 13/06, 16/06, 18/06, 01/09, 03/09, 11/09, 03/10, 10/10. Tsingy de Bemaraha: st’ns 08/96, 09/96. Distribution:A narrow-range endemic; known only from the Tsingy Beanka and Tsingy de Bemaraha, but common at both these localities. Habitat: Tall semi-deciduous and deciduous western dry forest. Often found on tree trunks after rain. Aestivates in leaf-litter. Remarks: Fischer-Piette et al. (1993) grouped medium-sized, low-spired Madagascan Tropidophora species together in their ‘groupe d’espèces du T. deshayesiana (Petit de la Saussaye, 1844) ’, but with the exception of T. vittata (Sowerby, 1843) all members of this group have much stronger spiral sculpture than T. humbug, including T. chavani Fischer-Piette, 1949 (see above) with which it is sympatric. Besides being relatively smooth, T. vittata, which is recorded only from north-eastern Madagascar (Fischer-Piette et al. 1993), shares with T. humbug a similarly banded colour pattern and is undoubtedly the most similar species. However, T. vittata has a far more prominent spire, deeper body whorl, narrower umbilicus, and a more extensively flared aperture lip, often with a wide extension in the columella region that partially obscures the umbilicus at full maturity. Fischer-Piette et al. (1993) stated that the holotype of T. vittata was in the NHMUK, but it could not be located there (Ablett in litt. Nov. 2011). T. semidecussata (Pfeiffer, 1847), is also similar and though a very variable species, like T. vittata, it has a more elevated spire, tumescent body whorl, narrower umbilicus and a more well developed, strongly reflected columella lip. Specimens of T. humbug from the Tsingy de Bemaraha commonly have a slightly more elevated spire than those from Tsingy Beanka, but H:D ratios for the two populations overlap considerably (H:D=0.47–0.61 compared to 0.46–0.53 respectively)., Published as part of 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, pp. 1-48 in African Invertebrates 54 (1) on pages 7-10, DOI: 10.5733/afin.054.0101, http://zenodo.org/record/7670100

Tropidophora secunda Fischer-Piette & Bedoucha, 1965 Figs 7, 8, 25C Cyclostoma reticulatum: Reeve 1861: pl. 9, fig. 48a, b [non Adams & Reeve 1850 in 1848–1850: 57, pl. 14, fig. 8]. Tropidophora reticulata: Fischer-Piette 1949: 36. Tropidophora secunda: Fischer-Piette & Bedoucha 1965: 76. Type loc.: Madagascar. Tropidophora (Ligatella) secunda: Fischer-Piette et al. 1993: 129, fig. 82. Morphological notes: External features (Fig. 25C): Head-foot more or less uniformly grey; tentacles and forehead slightly darker, paler toward mantle cavity; tip of snout conspicuously indented in mid-line; skin texture very finely granular. Operculum: Oligospiral; exterior portion a calcareous disc, attached to an inner and slightly larger corneous layer; external surface very shallowly concave, lacking a distinct convex spiral ridge (cf. T. humbug above), but with a diffuse, dark purple-brown spiral band more or less at mid-whorl, most noticeable on last whorl; edge of disc concave, with relatively weakly developed transverse partitions (adjacent to inner surface), except along smooth growing margin. Radula (Fig. 8): Formula 1+2+1+2+1; length 7.3 mm, ca 42 rows/mm; dentition fine. Rachidian with five distinct cusps, a minute additional pair sometimes discernable; central cusp largest and rounded, the outer pair small and curving inward. Inner laterals with four cusps, the inner cusp small and often obscured by the much larger second cusp; outer lateral with five or six cusps, the central three or four usually larger. Marginal teeth broad, the edge comprising three regions; an inner coarsely dentate element with ca 9 denticles; a more finely denticulate central region, and a smooth outer portion. Such a radula conforms to the pattern seen in Tropidophora (Ligatella) Martens, 1880 (Fischer-Piette et al. 1969). Locality data: Tsingy Beanka: st’ns 03/06, 11/06, 12/06, 13/06, 14/06, 15/06, 17/06, 18/06, 02/09, 11/09, R01/10, 03/10, 09/10. Kelifely Plateau: st’ns 04/05, 10/05. Anjajavy (Narinda north): st’ns 33/03, 36/03. 37/03, 38/03, 39/03, 40/03, 13/04 [abundant in this area]. Mtn d’Ambre/Ankarana: st’ns 12b/94, 01/01, 09/01 [uncommon]. Distribution: Central western to north-eastern Madagascar; from the southern Bemaraha region (Fischer-Piette et al. 1993) through Tsingy Beanka, the Kelifely Plateau and Anjajavy area, to Mtn d’Ambre and Ankarana in Antsiranana Province. Curiously, we have not found this species in our own surveys in the Tsingy de Bemaraha, nor at Antsingimavo, and whereas it is common in the southern Tsingy Beanka, it is rare in the central portion. Evidently although relatively widespread, the species has a somewhat patchy distribution within its range. Habitat: Dry deciduous, evergreen and riverine forest in limestone areas; in leaf-litter and sheltering microhabitats amongst rocks. Remarks: A characteristic species on account of its bold colour pattern. T. reticulata (Adams & Reeve, 1850), with which it was at one time confused, has a similar coloration, but is smaller (max. diameter approx. 16 mm, compared to> 18.5 mm in T. secunda), has a more elevated shell and a narrower umbilicus (Fischer-Piette 1949) (Fig. 26G–I, syntype, NHMUK). The white markings of T. secunda are not part of the shell fabric, but are a superficial chalky deposit which can be easily scraped off. Although previously reported from few localities, the range of T. secunda is evidently relatively large and it is not uncommon in undisturbed dry forest habitat. In contrast, the range of T. reticulata has yet to be established more precisely than ‘Madagascar’. Most specimens from Tsingy Beanka have a lower spire than the holotype (compare Figs 7A and 7F); however, shells of intermediate height are present both in the Tsingy Beanka and Kelifely Plateau (Fig. 5D, E). Fischer-Piette and Bedoucha (1965) selected as the ‘type’ for this species the specimen illustrated as Cyclostoma reticulatum by Reeve (1861: pl. 9, fig. 48a, b, ‘Mus. Cuming’), which they stated was present in the ‘British Museum’ [NHMUK]. Fischer-Piette (1949) had earlier examined this specimen, citing its diameter as 22 mm. No specimen identified as the holotype of Tropidophora secunda was present in the NHMUK, but a specimen labelled Cyclostoma reticulatum is present in the Cuming collection (Ablett pers. comm. Nov. 2011). This is 22 mm in diameter and closely resembles the figure given by Reeve (1861), though the colour pattern is not a perfect match. It seems very probable that this is the specimen referred to by Fischer-Piette and Bedoucha (1965), and we consider it to be the holotype of Tropidophora secunda (NHMUK 20110470, Fig. 7F–H). It is not clear why Fischer-Piette, after having examined the Cuming specimen illustrated by Reeve (1861) and designated it to be the type, subsequently stated for T. secunda ‘localisation du type:?’ (Fischer-Piette et al. 1993)., Published as part of 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, pp. 1-48 in African Invertebrates 54 (1) on pages 10-12, DOI: 10.5733/afin.054.0101, http://zenodo.org/record/7670100, {"references":["REEVE, L. 1861. Monograph of the genus Cyclostoma. In: Conchologica Iconica. Vol. 13. London: Lovell Reeve, pls 1 - 23."]}

Tropidophora sericea sp. n. Fig. 9 Etymology: From Latin sericeus (silky); in reference to the silky texture of the shell. Diagnosis: Spire very low, shell almost planorboid, body whorl not conspicuously tumescent, umbilicus very wide; columella lip weakly reflected, but not broadly expanded over umbilicus; sculpture finely decussate, comprising low, close-set spiral ridges crossed by similar axial pliculae; yellowish white with traces of fine orange-brown spiral lines. Description: Shell: Medium to large, depressed-discoidal to planorboid, spire very low with little other than embryonic whorls projecting in apertural view; final part of last adult whorl descending gently prior to aperture; whorls more or less evenly rounded, suture indented; umbilicus very wide, its margin evenly rounded; underside of embryonic whorls clearly visible. Protoconch of 1¼–1½ whorls, essentially smooth, but microscopically shagreened. Teleoconch of a further 2¾–3 whorls; first whorl initially with 6 or 7 low spiral ridges increasing to double this by end of whorl; ridges crossed by numerous, close-set axial pliculae producing a finely decussate sculpture; intervals between ridges 2–3 times wider than those between pliculae; subsequent whorls with additional spiral ridges arising by intercalation, but sculpture remaining finely decussate more or less throughout, including base; spiral ridges more close-set on later whorls and sculptural interstices less axially elongate; ridges with minute granules where crossed by axial pliculae. Aperture subcircular, strongly oblique to vertical axis of shell; peristome virtually complete, somewhat angled in parietal region; aperture expanding slightly prior to lip and lip also weakly reflected. Ground colour dirty white to yellowish buff; the freshest specimens retaining evidence of a pattern of fine orange-brown spiral lines above the periphery, that at periphery strongest; similar lines just below periphery but umbilicus and most of base lacking colour pattern. Dimensions: Holotype, max. diameter 37.3 mm, height 18.9 mm; largest specimen, max. diameter 41.4 mm. Holotype: MADAGASCAR: Central W Madagascar, ca 60 km E of Maintirano, NE of Belitsaka, central part of Tsingy Beanka, in slots and small caves above Bokarano R. gorge, next to low dry deciduous forest, 17.90517°S 44.48240°E, ca 215 m, 22.ix.2010, O. Griffiths & R. Randalana, st’n 09/10 (AMS C.474166). Paratypes: Same data as holotype (NMSA L8524 /T2979, 3 specimens); st’n 06/09 (AMS C.469585, 3 adult specimens); st’n 07/09 (TMAM T161, 1 adult specimen); st’n 08/09 (AMS C.469586, 9 adult specimens); st’n 08/10 (MHNP IM-2010-20083, 4 adult specimens). Additional locality data: Tsingy Beanka: st’ns 06/10, 07/10, 09/12. Distribution: A narrow-range endemic; currently known only from the central region of the Tsingy Beanka. Habitat: Found only in subfossil form in deep slots and crevices within the tsingy, in dry deciduous forest. Remarks: Like T. humbug, this species is referable to the ‘groupe d’espèces du T. deshayesiana (Petit de la Saussaye, 1844) ’ of Fischer-Piette et al. (1993). Within this group, it is closest to T. chavani Fischer-Piette, 1949 (see above) in having a very low spire, relatively fine spiral sculpture and a colour pattern of narrow, brownish, spiral bands. It is, however, considerably larger than T. chavani, attaining as much as 41.4mm in max. diameter (compared to 32 mm for T. chavani). Furthermore, its sculpture is considerably finer than that of T. chavani, with subequal spiral and axial elements. In T. chavani the axial pliculae are crisp, and much finer and more close-set than the spiral cords (compare Figs 9D and 9E).At some localities, T. chavani occurs in subfossil form together with T. sericea, but the two remain clearly distinct. T. moulinsii (Grateloup, 1840) (Fig. 26A–C, holotype, NHMUK) and T. thesauri Fischer-Piette, 1949 (Fig. 26D–F), both from the north-eastern tip of Madagascar, are of a more similar size (attaining 38 mm or more in max. diameter), but T. thesauri has much deeper whorls, a higher spire, narrower umbilicus, irregular scale-like subsutural pliculae and lacks the finely decussate microsculpture of T. sericea. T. moulinsii has stronger, cord-like, spiral sculpture, more tumescent whorls and a higher spire., Published as part of 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, pp. 1-48 in African Invertebrates 54 (1) on pages 13-14, DOI: 10.5733/afin.054.0101, http://zenodo.org/record/7670100

Seven new land snail species are described from the Antsingimavo and Beanka karst formations, northeast of Maintirano, central western Madagascar: Ampelita andriamamonjyi, A. beanka, A. lindae, Conulinus randalanai, Kalidos maryannae, Tropidophora humbug and T. sericea. Additional notes, records and illustrations are also provided for a further ten regionally endemic species.

Tropidophora insularis (Pfeiffer, 1852) Fig. 7 Cyclostoma insulare: Pfeiffer 1852: 64 (“ Isle de France ” – error; 13½ × 17 mm). A common species, recorded from seven inland stations, with a general distribution from South Africa to Kenya. “Described from a set in the Cuming collection labelled “ Mauritius,” a locality which Pfeiffer amended to “Natal” in his own working copy of his Monograph” (Connolly 1939: 547). Similar to, and probably a sister species of, T. ligata, with different ecological preferences since they do not co-occur at least in north-eastern Mozambique. Cases of co-occurrence in South Africa should be re-evaluated. Can easily be distinguished from T. ligata by the fairly strong spiral sculpture on the periphery as well as on the rest of the shell, the sculpture being weaker and not as dense and regular as in T. nyasana. It is much larger but otherwise very similar to the following species., Published as part of Muratov, Igor V., 2010, Terrestrial molluscs of Cabo Delgado and adjacent inland areas of north-eastern Mozambique, pp. 255 in African Invertebrates 51 (2) on page 263, DOI: 10.5733/afin.051.0203, http://zenodo.org/record/7913493

Tropidophora ligata (Müller, 1774) Figs 6, 56 Nerita ligata: Müller 1774: 181 (12.7–23.3× 12.7–21.2 mm). A common species, recorded from seven stations on Cabo Delgado and inland, with a general distribution from South Africa to Tanzania as well as on Madagascar and Mauritius. Differs from the other three species of Tropidophora in the region by the very weak spiral sculpture on the periphery of the last whorl, with most of the shells having noticeable spiral sculpture only in the umbilical area., Published as part of Muratov, Igor V., 2010, Terrestrial molluscs of Cabo Delgado and adjacent inland areas of north-eastern Mozambique, pp. 255 in African Invertebrates 51 (2) on page 263, DOI: 10.5733/afin.051.0203, http://zenodo.org/record/7913493, {"references":["MULLER, O. F. 1774. Vermivm terrestrium et fluviatilium, seu animalium infusoriorum, helminthicorum et testaceorum, non marinorum, succincta historia. 2. Havniae [Copenhagen] & Lipsiae [Leipzig]: Heineck et Faber."]}

Tropidophora zanguebarica (Petit, 1850) Figs 8, 57 Cyclostoma zanguebarica: Petit 1850: 53, pl. 3, fig. 5 (Ile de Zanzibar; 10–12 × 10–12 mm). Recorded from all three stations on Cabo Delgado, with a general coastal distribution from Kenya to Mozambique. Its relations with T. letourneuxi (Ancey in Bourguignat, 1887) should be re-evaluated (see remarks in Rowson 2007: 432). I prefer to use the earlier name here since variability of the shells from Cabo Delgado allows the application of both names. Resembles a small T. insularis but, unlike that species, co-occurs with T. ligata. Possibly just a coastal variation of T. insularis with size variability from 10.5×10.5 to 13.0×12.0 mm at a single locality., Published as part of Muratov, Igor V., 2010, Terrestrial molluscs of Cabo Delgado and adjacent inland areas of north-eastern Mozambique, pp. 255 in African Invertebrates 51 (2) on page 263, DOI: 10.5733/afin.051.0203, {"references":["PETIT, M. 1850. Notice sur le genre Cyclostoma, et catalogue des especes appartenant a ce genre. Journal de conchyliologie, comprenant l'Etude des Animaux, des Coquilles vivantes et des Coquilles fossiles 1: 36 - 55.","ROWSON, B. 2007. Land molluscs of Zanzibar island (Unguja), Tanzania with the description of a new species of Gulella (Pulmonata: Streptaxidae). Journal of Conchology 39 (4): 425 - 466."]}

Tropidophora nyasana (Smith, 1899) Fig. 5 Pomatias nyasanus: Smith 1899: 591, pl. 35, fig. 5 (Mount Chiradzulu, Nyika Range, Zomba Plateau; 20× 21 mm). Recorded from two stations on Cabo Delgado; has a general distribution in Malawi (type localities), Mozambique and Zimbabwe. Differs from the other three species of Tropidophora in the region by the presence of numerous regularly spaced spiral cords over the entire shell surface., Published as part of Muratov, Igor V., 2010, Terrestrial molluscs of Cabo Delgado and adjacent inland areas of north-eastern Mozambique, pp. 255 in African Invertebrates 51 (2) on page 263, DOI: 10.5733/afin.051.0203

ntroduction The fossils contained in this collection were procured from a number of localities in the northern and north-western parts of Madagascar by the Rev. R. Baron, during an extensive journey which he undertook in 1891, as an officer of the London Missionary Society. They may be regarded as supplemental to those that he collected some few years previously in the north-western districts, fossils which were described in 1889 before this Society as representative of Eocene, Cretaceous, and Jurassic rocks. The present collection, besides comprising organic remains from these different horizons, contains a few terrestrial shells referred to Achatina panthera, Achatina like A. Layardi, Buliminus ( Rachis ) punctatus , and Pomatias ( Tropidophora ) virgata . These were found in a Quaternary deposit capping the hill of Ambohimarina at a height of over 1400 feet above sea-level, and they are known to exist on the island at the present day. The Tertiary (Eocene) specimens consist entirely of foraminifera. They were obtained from the island of Antanifaly (N. W. coast) and have been determined as Nummulites allied to N. Bellardii, N. perforata, N. complanata , and Assilina spira ; species which have a wide distribution, though mostly confined to South European countries, Egypt, West Asian localities, and India. The Cretaceous fauna contributes one specimen of Lampadaster Grandidieri ?, found in a red limestone, immediately beneath the subsoil of Ambohimarina Hill, which also contains Frondicularia , etc., and dense masses of Globigerinae ; while examples of Belemnites pistilliformis prove the presence of Neocomian rocks north of Andranosamonta village. Among Jurassic fossils a