Dadagulella selene (van Bruggen & Van Goethem, 1999 ) Rowson & Tattersfield, 2013

Rowson, Ben & Tattersfield, Peter, 2013, Revision of Dadagulella gen. nov., the “ Gulella radius group ” (Gastropoda: Streptaxidae) of the eastern Afrotropics, including six new species and three new subspecies, European Journal of Taxonomy 37, pp. 1-46 : 25-26

Dadagulella selene (van Bruggen & Van Goethem, 1999) comb. nov.

Figs 36 , 84 ; Table 1

Gulella selene van Bruggen & Van Goethem, 1999: 39-40 , figs 11-12.

Gulella selene – van Bruggen 2000: 233.

Type material examined

DEMOCRATIC REPUBLIC OF CONGO: paratype RBINS. MT. 1645: 1 ad., Kivu Province, Virunga National Park, northern sector, Kalivina River, tributary of the Talya Nord River, bamboo forest, Hagenia Moench, 1000 - 2720 m (approx. 0.0° S, 29.5° E), leg. P. Vanschuytbroeck & H. Synave, 28 Aug. 1953 (examined digital photograph only).

Type locality

“D.R. Congo, Kivu Province, Virunga National Park, northern sector, at Musabaki (=Musavaki) River, 2720 m ” (van Bruggen & Van Goethem 1999) (approx. 0.0°S, 29.5°E).

Other material examined

None.

Description

SHELL ( Fig. 36 ). Medium-sized (3.60 - 3.70 mm high x 2.10 - 2.20 mm wide), of 6.0 - 6.25 whorls. Ovateacuminate, although spire (spire angle 70°) less acuminate than in other Dadagulella gen. nov. Apex rounded. Embryonic whorls “completely smooth, although there is a hint of spiral engraving” (van Bruggen & Van Goethem 1999). Later whorls with numerous, fine, very weak ribs (about 16 per mm on penultimate whorl). Sutures of intermediate depth. Umbilicus closed or nearly so. Peristome complete. Outer palatal surface of aperture with a depression corresponding to the palatal tooth. Dentition 5-fold, consisting of: one lamella-like parietal tooth; one bifid slab-like palatal tooth, not forming a parietopalatal sinus; a baso-columellar tooth or denticle; a deep-set columellar baffle and a shallower columellar tooth. Dentition alternatively recognisable as 6-fold, if the bifid palatal tooth is interpreted as two teeth (van Bruggen 1969). Juvenile shells and anatomy unknown.

Range and habitat

Montane forest (1000 - 2720 m) in the Albertine Rift. The type locality and the other in the Virunga National Park are in bamboo forest (van Bruggen & Van Goethem 1999). Wronski & Hausdorf (2010) also record it from montane forest at around 2300 m in Echuya Forest Reserve, southwestern Uganda.

Remarks

Van Bruggen & Van Goethem (1999) considered this species to belong to the group of species among which van Bruggen (1969) placed D. browni comb. nov. They noted that within this group D. selene comb. nov. was the most weakly sculptured and had distinctive dentition. These comments are still applicable among the larger number of species we attribute to Dadagulella gen. nov. However, like D. browni semulikiensis subsp. nov., D. selene comb. nov. is notable for occurring far to the northwest of other Dadagulella gen. nov species. It deserves further study from the perspective of Conogulella Pilsbry, 1919 (see Discussion).

Figures

Figs 36-40. Adult shells of Dadagulella gen. nov. species. 36. D. selene (van Bruggen & Van Goethem, 1999) comb. nov., holotype, Virunga NP (after van Bruggen & Van Goethem 1999). 37. D. meredithae (van Bruggen, 2000), holotype, Nyika NP. 38. D. minuscula minuscula (Morelet, 1877), lectotype, Nzwani. 39. D. minuscula minuscula, paralectotype, Nzwani. 40. D. minuscula mahorana subsp. nov., holotype, Mayotte.

Fig. 84. Distribution of Dadagulella gen. nov. species, based on published records and material examined here (for additional records of D. meredithae comb. nov. in northern Malawi see van Bruggen 2000). The inset on the left corresponds to the map on the right.