12 



A.V. SYSOEV 



concave, covered with wide, longitudinally rugose callus, which 

 does not form a pad at the sinus entrance. The anal sinus is deep, 

 narrows markedly towards the apex, U-shaped (type (c) of 

 Kilburn, 1988), and its deepest point is situated slightly below 

 the middle of subsutural slope. The canal is moderately long and 

 straight. H = 33.0, Hb = 18.4, Ha = 13.8, D = 10.3 mm. 



The paratypes vary slightly in the character of spiral 

 sculpture: the cords may be unevenly spaced, rarely with thinner 

 additional cords in some intervals. The subsutural fold is 

 variously developed, sometimes it is distinct. The canal is 

 narrower and sometimes curved in smaller shells and broader 

 and therefore visually shorter in larger paratypes. The largest 

 paratype is 34.3 mm in height. 



In the only paratype with an intact protoconch, it consists of 

 1 .5 rapidly increasing globose whorls (1 .0 mm in diameter) with 

 a smooth surface. An operculum was not found; it might be lost 

 in the dried animal. The radula (Fig. 2) is typical of the genus, 

 teeth with tapering distal end of the shaft, poorly differentiated 

 cutting edge, and large and broad accessory limb. The tooth 

 length is 0.17 mm (in paratype from stn 33, H = 34.3 mm). 



The new species resembles Funa laterculoides (Barnard, 1958) 

 in general outlines but clearly differs in its protoconch, colour, 

 radula, and details of sculpture. 



Distribution. Gulf of Aden, 1022-1295 m. 



Inquisitor indistinctus Sysoev, new species 



Figs 3, 1 1 & 54-55 



Material, stn 145, 3 specimens and 1 shell (holotype No. 

 1993097 and 3 paratypes No. 1993098). 



Description of holotype. The shell is medium size, 

 claviform, slender, with rather high spire, thin but solid, covered 

 with solid olivaceous periostracum, and consists of protoconch 

 and 9 teleoconch whorls. The protoconch is small (0.95 mm in 

 diameter) consisting of 1.5 smooth glossy whorls. Definitive 

 whorls weakly convex, with a slight angulation at the shoulder. 

 Subsutural slope concave except for weak subsutural fold. 

 Sutures straight, moderately deep, become slightly channelled 

 on the body whorl. The axial sculpture is represented by strong 

 oblique rounded folds, gradually disappearing on subsutural 

 slope and reaching the lower suture or, on the body whorl, the 

 shell base. The folds tend to weaken on the last half of the body 

 whorl. There are 14 folds on the body and penultimate whorls. 

 Spiral cords override the axial folds, they are low, wide and 

 rounded, the intervals are approximately equal to cords in width 

 or somewhat wider. There are 16 cords on the body whorl and 

 7-8 on the penultimate. The shell base is weakly convex, and 

 smoothly passes into the canal. The aperture is rather narrow, 

 elongate-oval, and not differentiated from the canal. The latter is 

 short and wide, somewhat expanded and shallowly notched at 

 the end. The anal sinus is moderately deep, rounded, 

 symmetrical, and occupies the entire subsutural slope. The inner 

 lip is covered with thick white callus with a free edge in the lower 

 part. Columella almost straight. H = 31.3, Hb = 16.5, Ha = 12.4, 

 D = 8.3mm. 



The paratypes are smaller (H no more than 27.4 mm) and vary 

 slightly in the prominence of the axial and spiral sculpture 



including the subsutural fold. In one paratype, there is a weak 

 but distinct callus pad at the entrance to anal sinus. The 

 operculum is oblanceolate, with terminal nucleus. Marginal 

 teeth of the radula possess broad leaf-shaped accessory limb, 

 which does not reach the distal end of the shaft. The mean tooth 

 length is 0. 1 4 mm (in paratype with H = 27.4 mm). 



Distribution. Maldive Islands, 494 m. 



Inquisitor stenos Sysoev, new species 



Figs 56 & 57 



Material, stn 176, 1 shell (holotype, No. 1993099). 



DESCRIPTION. The shell is rather small, slender, with high spire 

 comprising about 0.5 of the shell height, yellowish-white, and 

 consisting of 9 whorls. The protoconch is missing. Whorls are 

 strongly angled at the periphery, and the whorl profile is very 

 weakly concave above the angulation and almost flat below it. 

 There is a narrow and weak subsutural fold. Sutures are straight 

 and moderately deep. The axial sculpture consists of slightly 

 oblique and widely spaced folds (9 on each of two last whorls) 

 forming longitudinally elongated and sometimes pointed strong 

 tubercles in the middle of the whorl. On early spire whorls, the 

 folds are obsolete but visible on the lower part of subsutural 

 slope and reach the lower suture. Towards the body whorl, they 

 become obsolete near the lower suture and over most part of 

 subsutural slope, but again become longer and extend over entire 

 shell base in the last half of the body whorl. The last fold situated 

 behind the aperture edge is much wider and stronger than other. 

 Spiral sculpture consists of indistinct, rather broad ribs which 

 are obsolete or subobsolete in interstices between axial folds and 

 absent on the subsutural slope. The aperture is narrow, 

 elongate-oval, with a thick labial callus and straight columella. 

 The labrum has a thin edge and low and narrow fold-like varix 

 behind the edge. The anal sinus is moderately deep, U-shaped, 

 with slightly constricted entrance (type (b) of Kilburn, 1988). 

 There is a moderately large, pointed, and outwardly projecting 

 parietal tubercle. H = 21 .3, Hb = 10.7, Ha = 18.4, D = 5.7 mm. 



The new species is distinguished by its small narrow shell with 

 high spire, broad subsutural slope, low but strongly tuberculated 

 at the periphery axial folds, and obscure spiral ribs. 



Distribution. Gulf of Aden, 655-732 m. 



Inquisitor angustiliratus Sysoev, new species 



Fig. 58 



Material, stn 188, 1 shell (holotype, No. 1993100). 



Description. The shell is moderately large, with a rather high 

 spire, strong, yellowish-gray, and consisting of 8 whorls. The 

 protoconch is missing. Whorls are moderately convex, slightly 

 angled at the shoulder, with indistinct subsutural fold and 

 moderately wide (about 1/3 of the whorl height), concave 

 subsutural slope. Sutures are wavy, and slightly channelled. 

 Axial folds ( 1 2 on the body whorl and 1 1 on the penultimate one) 

 are narrow, slightly oblique, with sharpened crests, and long 

 (they reach the lower suture and extend over the entire shell 

 base). The folds begin in the lower part of the subsutural slope 



Figs 49-62 Crassispirinae. 49 - Inquisitor nodicostatus Kilburn, 1988, stn 106, H = 36.8 mm; 50-53 - /. adenicus Sysoev, new species, holotype (50) 

 and paratypes, stn 33 (51) and 34 (52-53), H = 34.3 (51), 30.9 (52) and 26.3 (53) mm; 54, 55 - /. indistinctus Sysoev, new species, holotype (54) and 

 paratype, stn 145, H = 26.0 mm (55); 56, 57 - /. stenos Sysoev, new species, holotype; 58 - /. angustilirata Sysoev, new species, holotype; 59, 60 - 

 Paradrilliaagalma (E.A. Smith, = 1906), stn 176,H= 15.3mm;61 -P. agalmal, stn 180,H= 14.4mm; 62- Ceritoturris sp., stn 42, H = 11.8 mm. 



