Eucnemidae

Oberprieler, Rolf G., Ashman, Lauren G., Frese, Michael & Ślipiński, Adam, 2016, The first elateroid beetles (Coleoptera: Polyphaga: Elateroidea) from the Upper Jurassic of Australia, Zootaxa 4147 (2), pp. 177-191 : 187

Eucnemidae ? Genus and species 3

( Figs. 17–18 )

Description. A small specimen comprising head, prothorax, elytra and parts of abdomen. Length 3.3 mm, width at base of pronotum 1.25 mm. Head broadly triangular but otherwise indistinct. Pronotum trapezoid in outline; anterior margin straight, anterolateral angles blunt, sides straight and slightly diverging posteriad; posterolateral angles acute, shortly produced, no carina indicated; basal margin gently arcuate; surface smooth, not distinctly punctate or granulate. Scutellar shield indiscernible. Elytra subtriangular, with acute apex; flat, intervals not apparently raised; 9 striae of large subquadrate punctures visible on disc. Metaventrite apparently smooth. Legs not preserved. Abdominal ventrites also smooth; sutures straight and equal in thickness (suggesting fusion of ventrites 4 and 5).

Material examined (1 specimen). Part (AM F. 141620) consisting of cuticular remains of head, prothorax and elytra and impression of abdomen; counterpart (AM F. 141621) comprising cuticular remains of abdomen and impression of head, prothorax and elytra. Talbragar Fish Bed ( Upper Jurassic : Kimmeridgian-Tithonian, 151 ±4 Ma), Gulgong, N.S.W., Australia, December 2015, coll. R. G. Beattie. Deposited in the Australian Museum, Sydney.

Remarks. The specimen differs from the holotype of Beattieellus jurassicus in its smaller size, different body dimensions (length-width ratio 2.64:1; 3.03: 1 in B. jurassicus ) and the anteriorly truncate prothorax (rounded in B. jurassicus ). The apparent absence of a carina on the posterolateral pronotal angles and fusion of the last two ventrites suggest that it may also be a eucnemid, but it is not well enough preserved to allow an unambiguous family assignment and it does not warrant a formal description and name.

Figures

FIGURES 17 – 20. Elateroidea Genus and species 3 & 4. 17, Genus and species 3, part (AM F. 141620); 18, Genus and species 3, counterpart (AM F. 141621); 19, Genus and species 4, part (AM F. 111180); 20, Genus and species 4, counterpart (AM F. 111179). Scale bars 1 mm.