Escheria punctulata Foerster , 1891

Martin, Fikacek, Hajek, Jiri & Schmied, Heiko, 2011, On the identity of the fossil aquatic beetles from the Tertiary localities in the southern part of the Upper Rhine Graben (Coleoptera, Hydrophilidae, Dytiscidae), ZooKeys 78, pp. 15-25 : 20

Escheria punctulata Foerster, 1891 Fig. 9

Escheria punctulata Förster 1891: 361; plate XI, Figs 8a,b (original description from Brunstatt); Handlirsch 1908: 767 (catalogue).

Hydrobius punctulatus : Théobald 1937: 169 (transferred to Hydrobius ); Hansen 1999: 319 (catalogue).

Taxonomic note.

Based on the drawing by Förster (1891), the ventral morphology of this species agrees with that of Hydrophilidae : Hydrophilinae in many characters: (i) mesocoxae transverse and very narrowly separated, (ii) mesepimeron well separated, triangular, (iii) metanepisternum rather narrow; (iv) abdomen with five ventrites. However, none of these characters or their combination is unique for the Hydrophiloidea and may be found in other beetle families as well (see Lawrence et al. 1999). Moreover, two characters illustrated on the drawing and/or mentioned in the original description exclude the placement of Escheria punctulata in the Hydrophiloidea : (i) elytra bear only 6 deeply impressed striae [9-11 striae are present in all Hydrophiloidea with striate elytra, only rarely is the number of series higher but in such cases they are never impressed to striae]; (ii) mesoventrite fused with mesepisternal (i.e. not separated from them by sutures) [in Hydrophiloidea , the mesoventrite is fused to mesepisterna only in derived groups of the Sphaeridiinae which are characterized by a highly elevated median portion of the mesoventrite; the elevated median elevation is missing from the fossil]. For these reasons, Escheria punctulata is removed from the fossil record of the Hydrophiloidea and is placed into Polyphaga incertae sedis; its family placement remains unclear.