Dadagulella nictitans Rowson & Tattersfield 2013, comb. nov.
Creators: name: Rowson, Ben
name: Tattersfield, Peter
Publisher: name: Zenodo
Year: 2013
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Gastropoda
Stylommatophora
Streptaxidae
Dadagulella
Dadagulella nictitans

description: Dadagulella nictitans (Rowson & Lange, 2007) comb. nov.
Figs 33, 84; Table 1
Gulella nictitans Rowson & Lange, 2007: 27-31, figs 4-7, 14-19.
Type material examined
KENYA: holotype NMK: 1 ad., Taita Hills, Macha Forest Reserve (3.45°S, 38.37°E), leaf litter in indigenous forest (site IB), 1550 m alt., leg. C.N. Lange, 27 Nov. 1998. Paratypes NMW. Z. 2007.024.00007-00009: 3 ads, data as holotype. Paratype NMW. Z. 2007.024.00010: 1 juv., data as holotype.
Other material examined
None.
Description
SHELL (Fig. 33). Medium-sized (3.60 - 3.90 mm high x 2.00 - 2.20 mm wide), of 5.5 whorls. Ovateacuminate, although spire (spire angle 64 - 69°) less acuminate than in other Dadagulella gen. nov. Apex rounded. Embryonic whorls smoothly granulate. Later whorls with relatively coarse ribs (13 - 15 per mm on penultimate whorl). Sutures of intermediate depth. Umbilicus closed or nearly so. Peristome complete. Outer palatal surface of aperture with a long, furrow-like depression corresponding to the palatal tooth. Dentition 5-fold or 6-fold, consisting of: one V-shaped parietal tooth; one slab-like palatal tooth, forming a conspicuous and narrow parieto-palatal sinus; and two to three shallow columellar teeth, the lower the largest. A deep set-columellar baffle is partly or completely hidden by the constricted aperture, while a basal denticle is completely hidden behind the palatal tooth. However, the baffle and basal denticle are probably present in all specimens. One broken juvenile shell is known; it appears to lack teeth.
CEPHALOPODIUM. Pale cream, with pale tentacle retractors.
SALIVARY GLANDS. United, soft, not tumid, elongate, Y-shaped; each duct leaving at the apex of the lobe and evenly thick throughout.
RADULA. Not successfully prepared.
GENITALIA. Figured in Rowson & Lange (2007).Vas deferens thickened prior to insertion on penis but apparently without diverticulum. Penial sheath absent. Interior of penis with weak radial pilasters, a single longitudinal pilaster, and small rhombic pads. Apical, muscular part of penis with two large hooks, associated with a spatulate “scoop” with microscopically serrated tip. Elsewhere in penis a single longitudinal row of short, simple hooks mounted on rhombic pads.
Range and habitat
Montane forest (1400 - 1900 m) at the type locality and three other Forest Reserves in the Taita Hills, southeastern Kenya (Rowson & Lange 2007).
Remarks
This species is included in Dadagulella gen. nov. on the basis of the apical penial scoop and hooks, and the Y-shaped salivary gland. Its shell features are consistent with inclusion in Dadagulella gen. nov. although the apex is more rounded than in other species. A slightly or strongly rounded apex occurs in D. selene comb. nov. and D. meredithae comb. nov. The parieto-palatal sinus, hidden basal denticle, and columellar dentition of D. nictitans comb. nov. allow it to be separated from other species.
description: Published as part of 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, pp. 1-46 in European Journal of Taxonomy 37 (37) on pages 22-23, DOI: 10.5852/ejt.2013.37, http://zenodo.org/record/3806770