Glyptelasma gracile (Hoek, 1883)

Pitriana, Pipit, Jones, Diana S., Corbari, Laure & Rintelen, Kristina von, 2020, New insights gained from museum collections: Deep-sea barnacles (Crustacea, Cirripedia, Thoracica) in the Museum National d'Histoire Naturelle, Paris, collected during the Karubar expedition in 1991, Zoosystematics and Evolution 96 (2), pp. 649-698 : 649

Glyptelasma gracile (Hoek, 1883) Figure 7

Poecilasma gracile Hoek, 1883: 46, pl. II, figs 2-4.

Megalasma gracile gracilius . - Pilsbry, 1907a: 88, pl. V, fig. 16, pl. VII, figs 6-9.

Megalasma gracile . - Nilsson-Cantell 1938: 10.

Megalasma (Glyptelasma) gracile . - Zevina 1982: 84, fig. 74.

Glyptelasma gracile . - Jones et al. 2001: 239.

Material examined.

- Tanimbar Island: 14 specimens, MNHN-IU-2019-4873, Stn. CP 54, 08°21'S, 131°43'E, 836-869 m depth, 30 October 1991, attached to spine of sea urchin; 1 specimen, MNHN-IU-2019-4875, Stn. CC 57, 08°19'S, 31°53'E, 603-620 m depth, 31 October 1991; 3 specimens (1 adult, 2 juveniles), MNHN-IU-2019-4876, Stn. CP 73, 08°29'S, 131°33'E, 840-855 m depth, 2 November 1991, attached to spines of sea urchins.

Diagnosis.

Capitulum with five plates; carina enlarged, keel-shaped; tergum with basal point truncated; maxillule notched; caudal appendages with relatively-long spines at tip.

Description.

Capitulum whitish, peduncle brownish. Capitulum compressed, striated, about twice as long as broad. Scutum with apex pointed; tergum basally truncated, flat, oblong. Carina flat, very narrow, enlarged, keel-shaped in basal region. Cirrus I with anterior and posterior rami equal length; cirrus II-VI long, slender; cirrus VI with small caudal appendages. Penis with few long hairs towards tip. Maxillule notched, with strong teeth on upper side; mandible with four teeth; labrum with row of small teeth on crest. Measurements of specimen: basal diameter of capitulum 1.45 mm; capitular height 10.44 mm; total height 13.99 mm; scutal width 4.79 mm; scutal length 9.01 mm; tergal width 1.87 mm; tergal length 5.07 mm.

Distribution.

West-southwest Pacific: from Australia (Sydney) to Indonesia (Sumbawa) and the Philippines (northwest Panay Island); East Indian Ocean; attached to glassy spicule of hexactinellid sponge, fragments of sea urchin tests, spines of cidarids; 395-935 m depth ( Jones and Hosie 2016). In this study, Glyptelasma gracile was found at Tanimbar Island, Indonesia.

Type locality.

Challenger expedition Station 164a (off Sydney, Australia); 34°13'S, 151°38'E; depth 125 m; bottom: grey ooze ( Hoek 1883).

Figures

Figure 7. Glyptelasma gracile (Hoek, 1883) (MNHN-IU- 2019 - 4875). a. left lateral view, capitulum and peduncle; b. right lateral view, capitulum and peduncle; c. anterior view, orifice; d. posterior view, carina. Scale bar: 2 mm (a-d).