Bullia granulosa (Lamarck, 1822)

Figs 9–15, 18–20, 43–55

Terebra granulosa Lamarck, 1822: 291 .

Complete synonymy in Cernohorsky 1984: 28; Adam & Knudsen 1984: 66 and Allmon 1990: 28.

Description:

Shell (Figs 9–13). Similar to preceding species. Differences:Color uniform bright purplebeige; aperture brown. Protoconch wider (Figs 9–11), occupying ~ of shell width in adult forms, dome-shaped, of two whorls (Fig. 13); boundary between protoconch and teleoconch unclear. Sculptured, with axial threads in first teleoconch whorl (Fig. 13), two series of subsutural nodes in remaining whorls, each node axially elongated, those closer to suture slightly smaller; growth lines in the rest of whorl. Region at left of aperture possessing ~ 8 spiral cords, somewhat uniformly distributed in left side of inner lip and canal (Figs 9, 10, 12), inferior cords slightly narrower than superior cords. Inner lip with small protuberance in base of canal (Fig. 12).

Head-foot (Figs 43, 44, 47). Characters similar to those of preceding species, including socket-like head (Fig. 44), bifid columellar muscle (Fig. 43: cm), and pair of small metapodial tentacles (Fig. 43: et). Differences: Head somewhat narrower, without eyes. Female lacking detectable cement gland at foot sole.

Operculum (Figs 14, 15). Elliptical, horny, pale brown. Nucleus inferior, subterminal but close to inferior edge. Outer surface with normal concentric growth lines, forming undulations. Scar oval, occupying about ½ of inner surface, somewhat dislocated closer to inner edge; flanked by strong and wide ridge in outer edge (Fig. 15).

Mantle organs (Figs 45, 46). Similar to those of preceding species. Remarks and differences: Low, broad fold of siphon’s right base separates anterior end of osphradium from gill and is somewhat taller (Fig. 46: sf). Osphradium (os) with filaments shorter, but with longer lateral projections (Fig. 45: os). Ctenidial vein (cv) relatively broader, weakly expanded at mid-level. Gill with much shorter filaments, apex approximately at mid-level (Fig. 45: gi). Anus shortly siphoned, located in front of anterior of pallial cavity (Fig. 46: an).

Visceral mass. Not seen in detail.

Circulatory and excretory systems (Fig. 46). Similar to preceding species, except that the dorsal side of the renal lobe is more developed (kl).

Digestive system (Figs 47–53). Main features and general plan similar to those of preceding species. Remarks and differences: Proboscis with similar arrangement, but possessing stronger transverse muscle, covering both ventral surface of rhynchodeal wall (Fig. 47: mf), and between oesophagus and odontophore in buccal mass (Fig. 49: tm). Odontophore proportionally shorter, ~50 % of length of proboscis (Fig. 49: od). Odontophore muscles with similar arrangement (Figs 50, 52, 53), except for: m1, no especially developed jugal muscle; mc, somewhat longer, reaching ~ 90% of length of cartilages up to region close to their posterior end (Figs 52, 53); m2b, originating as 4–5 branches, uniting themselves in region before entrance in odontophore (Fig. 52); m2c, slightly broader (Figs 50, 52); m2d, pair of auxiliary muscles of m2b, running externally, with same origin, inserting jointly with m2b (Figs 50, 52); m4, pair slightly broader (Fig. 52); m6, thin horizontal muscle, about 80% of cartilage length (Figs 52, 53); m9, similar, but only present as a single pair (Fig. 52); m9a, much more developed, about as wide as m4, broadly covering radular nucleus (Figs 52, 53). Subradular cartilage expanded in exposed region of radula into buccal cavity (Fig. 50: sc), covering neighbouring surface of radula; oc, odontophore cartilages similarly fashioned, except for greater extent of fusion, along ~10% their length (Fig. 53).

Radula similar to that of preceding species (Figs 18–20): rachidian with ~ 21 cusps and thinner; base of the rachidian less curved; lateral tooth also similar, with inner cusp rising from base being more pronounced (Fig. 19). Salivary glands with similar features, except for their ducts, with clear expansion in region in front of their aperture, situated within dorsal folds of buccal cavity (df), and salivary aperture more laterally positioned (Fig. 49: sa). Anterior oesophagus much broader, about as broad as odontophore (Figs 48, 49: ea). Valve of Leiblein also broader (Fig. 48: vl), with well-developed inner cilia (Fig. 51: vc). Middle and posterior oesophagus with similar characters (Figs 48, 51: em, ep). Gland of Leiblein very narrow, elongated, filiform (Figs 48, 51: gl); ~ 3× longer than middle oesophagus and ~10× narrower than it; twisted between anterior and middle thirds, just in region where aorta passes (Figs 48: aa). Duct of gland of Leiblein almost undetectable, aperture simple (Fig. 51: ga). Stomach and intestine not examined in detail. Rectum and anus described above (pallial cavity).

Genital system. Male. No male was available for examination.

Female (Fig. 46). General features similar to those of preceding species; except for relatively shorter albumen gland (ag) and female pore (fp) being situated further away from anus. No cement gland detectable.

Central nervous system (Figs 54, 55). Similar to that of preceding species, except for narrower commissure of buccal ganglia (Fig. 55: bg), and longer commissure between cerebral ganglia. Statocyst located in antero-ventral region of pedal ganglia (sy).

Measurements of shells. MNHN 1♀: 29.4 × 10.7 mm.

Distribution: From Morocco to Democratic Republic of the Congo.

Habitat: Sandy bottoms, ~ 15 m depth.

Material examined: 1♀, 1 shell: MOROCCO: Agadir Bay; Qued Sours, off Sousse River estuary, 30°22'N 09°37.9'W, from 15 m depth, MNHN, (Radial I; sandy bottoms, Moukrin & Gofas col. 08.v.1999) .