Litoscalpellum intermedium

Litoscalpellum intermedium (Hoek, 1883)

Fig. 5

Scalpellum intermedium Hoek, 1883: 70, pl. VI, fig. 13, pl. VIII, figs 6–8; Nilsson-Cantell, 1921: 208–213, text-fig. 33a–h. Scalpellum nipponense Pilsbry, 1907a: 73, fig. 29; Broch, 1931: 24, fig. 9; Hiro, 1933: 25, text-fig. 5, pl. 1, figs 7–9b; 1937b:

43, fig. 34; Utinomi, 1958: 283.

Litoscalpellum nipponense: Newman & Ross, 1971: 112–114, text-fig. 58.

Arcoscalpellum intermedium: Foster, 1978: 62, pl. 8B, fig. 37.

Gymnoscalpellum intermedium: Foster, 1980: 529, fig. 1f–g.

Litoscalpellum intermedium: Zevina, 1981a: 120–121, fig. 83; Liu & Ren, 1985: 196–197, fig. 8, pl. 3 (3–8); 2007: 228–230, fig. 96; Jones et al., 1990: 4, 26; Huang, 1994: 516; 2001: 318; Jones, 2012: 371, table 2.

Material examined. Three syntypes from two locations, in a single jar NHM UK 2013.1068-1070, Stn 164A: Pacific, Southwest (Tasman Sea), 750 m (Hoek, 1883: 71). Stn 169: Pacific, Southwest (off East Cape, New Zealand); 1280 m.

Supplementary descriptions. Nilsson-Cantell (1921), Foster (1978) and Liu & Ren (2007).

Distrbution. Pacific, Southwest and Northwest. Known depth range 365 to 1280 m.

Remarks. Foster (1980) inferred that the degree of reduction of the shell plates in L. intermedium increases with growth. After the capitulum reaches about 10 mm in length, the tergum, scutum, upper latus and carinal latus all bifurcate and become more widely separated, which was recognised by Newman & Ross (1971) as typical for the genus Gymnoscalpellum. Unfortunately, the quality of Foster's photographs of the early stages does not allow comparison of shell plate details between his specimens and those of Hoek (1883). Newman & Ross (1971) also noted the similarity between this species and Gymnoscalpellum tarasovi. It is clear that more detailed study of appendage morphology and/or analysis of molecular data will be needed to confirm the correct generic placement of this species.