Hexelasma arafurae Hoek, 1913

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

Hexelasma arafurae Hoek, 1913 Figure 32

Hexelasma arafurae Hoek, 1913: 251, pl. 25, figs 12-16. - Utinomi 1965: 11. - Newman and Ross 1971: 155. - 1976: 46. - Foster 1981: fig. 6F-H. - Jones 2000: 246, fig. 51, tables 28-31.

Aaptolasma arafura . - Foster, 1978: 79.

Material examined.

- Kei Islands: 2 specimens, MNHN-IU-2019-4851, Stn. DW 18, 05°18'S, 133°01'E, 205-212 m depth, 24 October 1991.

Diagnosis.

Shell with very wide orifice; alae broadly-triangular with summits oblique; scutum folded longitudinally, articular ridge slightly prominent, deep pit for adductor muscle; tergum beaked, with prominent articular ridge, spur very broadly rounded; inner side of scutum and tergum orange-coloured.

Description.

Shell yellowish, conical, with six plates. Orifice diamond-shaped; scutum triangular elongated with protruding growth-ridges; tergum smaller than scutum, apex beaked, carinal margin rounded, growth-ridges less distinct than on scutum. Cirrus I with unequal rami (anterior ramus: 8-segmented; posterior ramus: 12-segmented), dense long setae on surface areas. Cirrus II with equal rami, dense long setae. Cirri IV-VI with equal rami with numerous segments; segments almost without exception furnished with two pairs very long, stiff, needle-like spines along inner faces. Measurements of specimen: basal length of shell 14.32 mm, orifice length 8.00 mm, carinal height 12.39 mm, orifice width 6.49 mm, basal width 13.76 mm.

Distribution.

Arafura Sea, Indonesia; 205-560 m depth ( Jones and Hosie 2016). In this study, Hexelasma arafurae was found at Kei Islands, Indonesia.

Type locality.

Indonesia; Siboga stat. 262; 5°54'S, 132°49'E; 560 m depth; bottom: solid bluish-grey mud ( Hoek 1913).

Figures

Figure 32. Hexelasma arafurae Hoek, 1913 (MNHN-IU- 2019 - 4851). a. view from above; b. right lateral view. Scale bar: 4 mm (a, b).