Bretskya scapula, Glover & Taylor, 2007

Glover, Emily A. & Taylor, John D., 2007, Diversity of chemosymbiotic bivalves on coral reefs: Lucinidae (Mollusca, Bivalvia) of New Caledonia and Lifou, Zoosystema 29 (1), pp. 109-181 : 170-172

publication ID	https://doi.org/ 10.5281/zenodo.5392295
DOI	https://doi.org/10.5281/zenodo.5468591
persistent identifier	https://treatment.plazi.org/id/039087F4-FFFC-6A1D-121F-FA5FFEB3D54A
treatment provided by	Marcus
scientific name	Bretskya scapula
status	sp. nov.

Treatment

Bretskya scapula View in CoL n. sp.

( Figs 39B View FIG ; 40 View FIG ; 41 View FIG )

TYPE MATERIAL. — Holotype: 1 sh, L 6.8 mm, H 4.4 mm, T 1.4 mm ( BMNH 20050579 ).

Paratypes: from type locality, 1 sh, L 6.8 mm, H 5.5 mm, T (2v) 3.2 mm ( BMNH 20050580 ) ; 1 sh, L 6.7 mm, H 6.2 mm, T(2v) 3.3 mm ( Conchology Inc. Reference Collection , Philippines). — Figured paratypes: from type locality, 1 sh, L 6.3 mm, H 5.6 mm, T 1.6 mm ( MNHN) ; 1 sh, L 5.0 mm, H 3.8 mm, T (2v) 2.2 mm ( BMNH 20050580 ) ; 1 sh, L 6.8 mm, H 6.1 mm, T (2v) 3.2 mm ( BMNH 20050580 ) ; 1 sh, L 6.0 mm, H 4.5 mm, T (1v) 1.3 mm ( BMNH 20050580 ) ; 1 sh, L 4.0 mm, H 3.0 mm, T (2v) 1.9 mm ( BMNH 20050580 ) .

TYPE LOCALITY. — Philippines, Pipe Point, Pandanan Island, Jetafe, Bohol, 10°10.34’N, 124°05.94’E, 5 m, muddy sand, 12.III.2005, col. P. Poppe.

ETYMOLOGY. — Latin scapula , shoulder blade – in reference to the shape of this bivalve.

MATERIAL EXAMINED. — Touho. Stn 1249, 20°49’S, 165°19’E, 80-140 m, 1 RV, L 8.5 mm, H 7.7 mm ( MNHN).

Philippines. MUSORSTOM 3, stn DR 140, 11°43’N, 122°34’E, 93-99 m, 8 v ( MNHN).

DISTRIBUTION. — Recorded only from Philippines and New Caledonia at depths from 5- 100 m.

DESCRIPTION

Small, thin-shelled, H to 6.9 mm, L to 8.4 mm, outline irregular elongate ovoid, truncate to sinuate posteriorly, longer than high, H/L 0.68-0.82; highly anteriorly extended, slightly inflated. Umbones prominent, usually in posterior part of shell. Protoconch 160 µm long, PI 85 µm. PII with marked growth increments. Shell sculpture of irregular, thin, low, commarginal lamellae and fine growth increments, shell surface often distorted and plicate. Anterior dorsal margin elongate. Posterior dorsal margin steeply sloping. Lunule narrow, lanceolate. Ligament large, set on elongate resilifer. Hinge with two small, cardinal teeth in left valve and one in right valve, lateral teeth absent. Anterior adductor muscle scar short, reniform, detached from pallial line for about 1/3 of length. Pallial line entire. Shell margin smooth.

REMARKS

The material from the Philippines, on which this new species and genus is based, consists of seven livecollected shells. The characters are highly distinctive and unlike any other known lucinid. Although we have only a single right valve of this species from New Caledonia, it matches the characters of the type specimens.