Treijathana tureiae, 2005

Achituv, Yair & Langsam, Yaacov, 2005, Coral-inhabiting barnacles (Cirripedia; Thoracica; Balanomorpha; Pyrgomatinae) from east of 150 ° W, Journal of Natural History (J. Nat. Hist.) 39 (20), pp. 1705-1717 : 1711-1712

TreIJathana tureiae Achituv sp. nov.

( Figure 4 )

Material examined

Holotype: MNHN-Ci 2966 from Goniastrea sp. MNHN-Scle 20271 (field number TUR 6 e [ T VI, p 1067, 1060]). Opercular valves. French Polynesia Tuamotu Archipelago; Tureia Island; 20 ° 50 9 S, 138 ° 33 9 W, 4 November 1965, coll. Chevalier; MUSEUM II (CEA) Expedition.

This barnacle was found together with Neotreυathana elongatum and Saυignium tuamotum on the same piece of Goniastrea .

Diagnosis

Shell fused, oval, scutum transversally elongated more than four times as long as wide, adductor ridge missing deep adductor ridge, tergum triangular, spur distinct, no inner tooth.

Description

Shell white; fused, flat, oval, rostro-carinal diameter 3 mm; coral skeleton covering most of concentric growth ridges. Scutum and tergum white, separate. Scutum transversally elongate, four times longer than wide, rounded tooth projecting at tergal margin. Outer surface with growth ridges, closed furrow nearly parallel to occludent margin. Inner surface adductor ridge absent, adductor pit deep, elongated; lateral depressor muscle pit elongated, shallow. Tergum triangular, externally with growth ridges, internally with shallow depression accommodating scutal tooth; growth lines inside depression. Spur low, inwardly projecting, teeth absent.

Etymology

The specific name has been derived from the locality where this species was found, Tureia Island.

Remarks

The description and separation of this species is based on the form of the opercular valves. The shell is similar to those of other species of Treυathana and it is impossible to separate the species on this basis. The scutum and tergum are similar to those of Treυathana dentata , the characters that separate this species from T. dentata are the scutum without an adductor ridge. The tergum has spurs that project inward perpendicular to the inner surface of the tergum and does not carry the internal tooth of the tergum. The revised diagnosis of Treυathana ( Asami and Yamaguchi 2001) indicates the presence of an internal spur tooth. The dominant features of the opercular valves of Treυathana are the elongated scutum with prominent rounded tooth projecting at tergal margin that join the tergum, and the triangular tergum. We suggest that the diagnosis of the genus should be amended and would not include the presence of internal tooth of the tergal tooth, this character is specific to Treυathana dentata , a sister species to Treυathana tureiae . On the basis of these differences we suggest that they will be assigned to a new species.

Figures

Figure 4. Treυathana tuariae from Tuamotu Archipelago; Tureia Island. SEM micrographs of opercular valves. Scale bars: 2 mm (A, B); 1 mm (C, D).