Claviderma amplum Ivanov & Scheltema 2008, n. sp.
Creators: name: Ivanov, Dmitry L.
name: Scheltema, Amélie H.
Publisher: name: Zenodo
Year: 2008
Subjects: Biodiversity
Taxonomy
Animalia
Mollusca
Caudofoveata
Chaetodermatida
Prochaetodermatidae
Claviderma
Claviderma amplum

description: Claviderma amplum n. sp.   
(Figures 1B, 4D–F, 5, 6, 24B, 25; Tables 1, 2, 3b, 4a)  
 Type material: Holotype USNM 1112615. Paratypes: USNM; TAMU; ZMUM Le1–167 (DGoMB, S35/1), Le1–168 (DGoMB, MT3 /3), Le1–169 (NGoMCS sample 4443, station E2a/5).   
 Type locality: Gulf of Mexico, 28°16.77'N, 86°14.76'W, 622 m (NGoMCS, sample 4454, station E2/4, 19/05/1985).   
 Material examined: SE Florida coast, 33 specimens (Table 3b); Gulf of Mexico, 81 specimens (Table 1); Guiana Basin, 14 specimens (Table 4a).   
 Diagnosis: Slender, elongate, opaque, length to nearly 1 centimeter, posterium long, narrow, ¾ trunk length or greater; trunk sclerites but not shank sclerites adpressed, at 45º to longitudinal body axis; sclerites fringing knob in single row scarcely extending beyond knob. Oral shield sclerites in 5 rows, not obvious. Trunk sclerites long, to 600 µm, thick, symmetrical, proximal end narrow, waist distinct, blade short, wider than or equal to width of base, edges of blade convex, tapered to sharp distal point.   
 Etymology: L. amplus, -a, um = large.   
 Description: External appearance (Figs 1B, 5A–C): Body opaque, long for a prochaetodermatid, to 9.0 x 1.7 mm, shank narrow, long, posterium/trunk index 0.73–0.95, trunk width ~1/3 trunk length, holotype length 8.3 mm, anterium 0.2 mm, trunk 4.8 x 1.5 mm, shank 2.6 x 1.0 mm, knob 0.9 mm, posterium/trunk index 0.73; shank shaggy, narrower than and set off from smooth, elongate trunk; adpressed trunk sclerites diverging from ventral midline, converging along dorsal midline; fringing sclerites in single row extending to end of or beyond cone-shaped knob. Oral shield 0.12–0.15 mm in height, innermost of 5 rows of oral shield sclerites very small.   
 Sclerites (Figs 4D–F, 5G, 6): General: curved toward body, distal tip lifted (Fig. 6J), base long, 2 to nearly 3 times blade length, tapered proximally to narrow, rounded proximal end, narrowing at waist; blade wider than base at waist, sides nearly straight to convex, tapered to distal point; thickest on base medially or just below waist. Beside oral shield (Fig. 6A): somewhat quadrate, asymmetrical, angular proximally and distally, thick, 75 x 40 x 7 µm, thickest medially. Dorsal to oral shield (Fig. 6B): very thin pointed scales, 50 x 25 x 2 µm, elongating to flame-shaped, 90 x 20 x 3 µm. Anterium (Fig. 6C): long, narrow, with distinct waist, blade equal to or wider than base, to 150 x 20 x 6 µm. Dorsal trunk (Fig. 6E, F): blade less than 1/3 total length, to 600 x 40 x 15 µm, thickened symmetrically, thickest on base near waist. Ventral trunk (Fig. 6D): similar to those from dorsal trunk, but most shorter with about same width, thickest medially on base. Shank (Fig. 6G): shorter than posterior trunk sclerites, base broadest and straight proximally, tapering to pointed distal end, waist indistinct, slightly curved, from short and broad 220 x 60 µm to longer and narrower 400 x 45 x 9 µm, thickest medially or on upper third. Fringing (Fig. 6I): long, straight, narrow, to 1,000 x 25 x> 10 µm.   
 Radula and jaws: 2 examined. Jaws 920 x 400 µm (Fig. 5F); radula teeth 195 µm long, serrated membrane about 110 µm, situated almost medially; central plate asymmetrical, to 90 µm (Fig. 5E).   
 Distribution (Figs 24B, 25; Tables 1, 2, 3b, 4a): A continental slope species in the Gulf of Mexico (400– 1,032 m), off the southeast coast of Florida (293–342 m), and Guiana Basin (508 and 1,000 m). The greatest number of specimens in quantitative box core samples was 104 m -2 at 667 m in the Gulf of Mexico (Table 1, S35/2).   
 Remarks: Claviderma amplum is a large, slender species with a long, narrow "tail", the trunk and posterium of almost equal length. The sclerites of Cl. amplum are nearly indistinguishable from those of Cl. crassum, both having very long, narrow trunk sclerites with short, convex-sided blades. The two species are sympatric in the Guiana Basin, but not the Gulf of Mexico. Body morphology of the two differs particularly in trunk width and in length of posterium (short in Cl. crassum) and is often sufficient for distinguishing them. Cl. amplum does not reach the volume size of the largest specimens of Cl. crassum. See Remarks under Cl. crassum for particular differences.
description: Published as part of Ivanov, Dmitry L. & Scheltema, Amélie H., 2008, NMR solution structures of KAP- 1 PHD finger-bromodomain, pp. 1-60 in Zootaxa 1885 on pages 11-14, DOI: 10.13018/bmr11036, http://zenodo.org/record/5133706