Galaxias parvirostris Schwarzhans, 2012

Schwarzhans, Werner, Scofield, R. Paul, Tennyson, Alan J. D., Worthy, Jennifer P. & Worthy, Trevor H., 2012, Fish remains, mostly otoliths, from the non-marine early Miocene of Otago, New Zealand, Acta Palaeontologica Polonica 57 (2), pp. 319-350 : 330

Galaxias parvirostris Schwarzhans sp. nov.

Fig. 6E–G.

Etymology: From Latin parvus, small, and rostrum, technical term for the anterior tip of the otolith below the sulcus, referring to the short rostrum.

Type material: Holotype: NMNZ S.52720, ( Fig. 6E) . Paratypes: 3 specimens (2 specimens NMNZ S.52721, same location as holotype, 1 specimen NMNZ S.52722, Home Hills Station , Manuherikia River near St Bathans, HH 1a bed) ( Fig. 6F–G) .

Type locality: Vinegar Hill , site 2, Otago .

Type horizon: Bannockburn Formation, early Miocene.

Diagnosis.—Thick otoliths with compressed, rounded outline with very short rostrum. Inner face convex. Excisura small. Posterior rim rounded. Ostium narrow, short; cauda longer than ostium, terminating close to posterior rim of otolith. Ventral field on inner face wide, with indistinct ventral furrow.

Description.—Compressed thick otoliths with rounded outline. Size up to 2.5 mm. Rostrum short, blunt; excisura small; antirostrum indistinct. Posterior tip broadly rounded. Dorsal rim high, rounded, postdorsally pronounced. Ventral rim moderately deep, rounded. All rims smooth. OL:OH = 1.05– 1.2; OH:OT = 2.2–2.8.

Inner face markedly convex, somewhat rugged, with long, narrow, deepened, nearly median sulcus. Ostium very narrow, anteriorly open; cauda similarly narrow, straight, reaching close to posterior rim of otolith. OL:SuL = 1.05–1.1; CaL:OsL = 2.5–3.0. Dorsal field wide, with small, shallow depression. Ventral field wide, with indistinct ventral furrow at some distance from ventral rim of otolith.

Outer face flat to slightly convex, rather smooth.

Remarks.— Galaxias parvirostris is a rare species almost exclusively known from the location Vinegar Hill: only one specimen was found in the HH1a bed of the Manuherikia River location, which is the richest otolith bearing level in the Bannockburn Formation. It is easily recognized and best distinguished from other species by the rounded outline, the thick appearance and the very short rostrum and ostium.

Stratigraphic and geographic range.—Bannockburn Formation, Manuherikia River and Vinegar Hill.