Corrosella herreroi (Bech 1993)

Shellovate-conic (Figure 5A–C), yellowish periostracum with 4–4.5 spire whorls, height around 2.0–3.0 mm (Table 2); protoconch approximately 450 µm wide with 1.5 whorls and a nucleus around 200 µm long (Figure 5E, F); protoconch microsculpture grooved (Figure 5G); body whorl about 2/3 total length; whorls convex with deep suture; peristome frontal, complete, oval, with thick inner lip partly hiding umbilicus; outer peristome simple, straight (Figure 5D). Operculum corneous, yellowish, thin, pliable, ellipsoidal, paucispiral, with nucleus submarginal (Figure 6A, B; Table 3); oval muscle attachment near nucleus. Radula with around 50 rows of teeth, medium in size (25% total shell length) (Figure 6C, Table 4); central tooth with a tongue-shaped median cusp and five lateral cusps, slightly sharpening towards central one (Figure 6D, E); lateral teeth with a long tongue-shaped median cusp and three tapered laterals; inner and outer marginal teeth bear 15 and 19 sharp cusps respectively (Figures 6D, F). Pigmentation and anatomy: Head intensely brown pigmented from snout to neck (Figure 7D); pigment on neck clearer than on head; brown band of pigment also on tentacles, but not on ocular lobes; snout as long as wide, with medial lobation; foot intermediate length, pigmented on dorsal region. Ctenidium in the anterior region of pallial cavity with about 15 gill filaments; osphradium ellipsoidal under central gill filaments (Figure 7C, Table 5). Stomach slightly longer than wide (Figure 7F); style sac barely shorter than stomach, protruding below intestine (Table 5). Female genitalia with a pallial oviduct about four times longer than wide (Figure 7G; Table 6); capsule gland slightly longer than albumen gland and denser in posterior region; genital aperture in the anterior extreme of pallial oviduct; elongate bursa copulatrix, J-shaped folded with a duct less than 50% bursa length; renal oviduct scarcely pigmented from the insertion point of bursal duct to where it begins to fold and black pigmented, making two or three loops; elongate seminal receptacle with pigmented short duct (Figure 7H) joining renal oviduct slightly above the point where the bursal duct joins the renal oviduct. Male genitalia bearing a bean-like prostate gland about three times longer than wide (Figure 7E, Table 6); penis triangular with a wide base attached to central area of head with some folds in middle section and a narrow patch of black pigment on distal surface (Figure 7D); vas deferens uncoiled in penis running straight close to the external margin. Nervous system brown pigmented, but ganglia darker than connectives and commissures; cerebral ganglia equal in size; supraoesophageal and suboesophageal ganglia similar in shape and size; supraoesophageal connective around three times longer than suboesophageal (Figure 7A, B; Table 7). Mean RPG ratio 0.51 (elongated).