Tellimya tahaia, Raines & Huber, 2012

Raines, Bret & Huber, Markus, 2012, 3217, Zootaxa 3217, pp. 1-106 : 59-60

Tellimya tahaia sp. nov.

Figures 30 A–F

Type Material. Holotype: LACM 3161, 1 single RV, 6.9 mm. Paratypes 1–2: LACM 3162, 1 single RV, 6.8 mm and 1 single LV, 5.5 mm Motu Iti, Easter Island , dredged in 65 m.

Type Locality. Dredged at 30–50 m in fine sand, off the western coastline near Tahai , Easter Island, 27°07’20” S, 109°26’30” W. Mode of life and host are unknown .

Description. An ovate, comparatively large Tellimya species fragile in structure with rounded posterior margin. Shell small, below 7 mm, ovate, narrower and shorter posteriorly, equivalve, inequilateral with umbones closer to the rounded posterior end; thin; umbones rounded, broad, orthogyrate. Prodissoconch, P1 small, but typically worn away, P2 ovate, boundary ill defined, faint commarginal lines nearly obsolete, ca. 317 µm length by 220 µm height. Nepioconch with weakly raised radial lines. Adult shell white internally and externally with irregular opaque blotches; weakly inflated, non-gaping, surface superficially smooth. Hinge simple; in both valves with a strong anterior lateral, directed ventrally. Behind this front tooth follows a deep resilial recess. Its posterior end is followed by an oblique, characteristic, tooth-like ridge. Pallial line continuous and comparatively broad; muscle scars unequal, the narrowly shaped anterior scar is significantly larger; the posterior scar is rounded-ovate. Ligament internal and subumbonal. Margins smooth, very fragile.

Comparative diagnosis. Comparable to the new species is T. pauciradiata also from EI. Both share a very similar dentition. However, the posterodorsal margin of T. tahaia is evenly rounded, not bulged as in T. pauciradiata and in the type species T. ferruginosa . The shape of T. tahaia is higher and significantly shorter. Consequently, the umbones are broader and more pronounced. Tellimya tahaia is not known to reach the large size of T. pauciradiata . Whereas T. pauciradiata is commonly encountered, T. tahaia has only been rarely found.

The three New Zealand species are significantly distinct in shape. Moreover, T. benthicola and T. reinga have an anterior lateral which is less pronounced and they live in deeper water.

Remarks. There is nothing similar known from the Hawaiian or Marquesas Islands.

Distribution. Tellimya tahaia is rather rare and only known from the type locality and Motu Iti— E1.

Etymology. The name reflects the type locality.