Annandaleum lambda (Annandale, 1910) Figure 16

Scalpellum lambda Annandale, 1910b: 115. - 1916a: pl. VII, figs 6, 6a, pl. VIII, figs 12-15.

Scalpellum longius Annandale, 1913: 234.

Annandaleum lambda . - Newman & Ross, 1971: 122. - Jones, 1992: 154, fig. 6.

Material examined.

- Tanimbar Island: 10 specimens, MNHN-IU-2019-4915, Stn. CP 52, 08°03'S, 131°48'E, 1244-1266 m depth, 30 October 1991; 1 specimen, MNHN-IU-2019-4913, Stn. CP 53, 08°18'S, 131°41'E, 1026-1053 m depth, 30 October 1991; 1 specimen, MNHN-IU-2019-14, Stn. CP 89, 08°39'S, 131°08'E, 1058-1084 m depth, 5 November 1991, attached to pumice.

Diagnosis.

Capitulum narrow; carinal margin strongly curved; laterally compressed; bearing fourteen imperfectly formed, thin, smooth, translucent plates, eight formed like a Greek lambda.

Description.

Capitulum with 14 plates. Peduncle shorter than capitulum, cylindrical, rather slender, expanded at base. Tergum lambda-shaped, with prominent tooth on carinal margin just above point where apex of carina approaches it. Scutum shaped similarly, but occludent branch much stouter, with vertical ridge running nearer to lateral than occludent margin. Cirrus I unequal, anterior ramus oval, posterior ramus slender, long; cirri II-VI slender, long, with rami almost equal length; cirrus VI with long, slender caudal appendages. Maxillule not notched, two major setae on upper side; mandible with four teeth including inner angle. Measurements of five specimens: height of capitulum 16.61-24.27 mm, width 8.73-14.49 mm, thickness 3.17-6.31 mm; length of peduncle 5.54-15.27 mm, width 3.73-6.26 mm.

Distribution.

Indo-Pacific from off Zanzibar, Indian Ocean, eastern Australia; Sumbawa, Indonesia; Malay Arch.; SW of Calatagan Pt, Philippines; S Japan (S of Honda I.), SW Pacific; attached to shells of bivalves; 234-2077 m depth (Jones and Hosie 2016). In this study, Annandaleum lambda was found at Tanimbar Island, Indonesia.

Type locality.

Eastern Indian Ocean (13°54'15"N, 94°02'15"E), Investigator Stn. 372; 1,176 m depth (Jones 1992).