Hyphydrus ovatus (Linnaeus, 1760)

Bergsten, Johannes, Weingartner, Elisabeth & Hajek, Jiri, 2017, Species delimitation of the Hyphydrusovatus complex in western Palaearctic with an update of species distributions (Coleoptera, Dytiscidae), ZooKeys 678, pp. 73-96 : 75

Hyphydrus ovatus (Linnaeus, 1760)

Dytiscus ovatus Linnaeus, 1760: 547 (type locality: Svecia [Sweden]). For full list of synonymy, see Nilsson & Hájek (2017a: 199).

Material examined.

We have examined more than 600 specimens from the Czech Republic, Finland, France, Germany, Great Britain, Russia, Slovakia, Sweden, and Ukraine, deposited in NHRS and NMPC.

Diagnosis.

Habitus as depicted in Figs 4b, 5b. Clypeus with anterior margin medially nearly straight (Fig. 6b). Reticulation of dorsal surface confined to head, more distinct and impressed anteriorly (Fig. 6b). Punctation of head fine, visible only in posterior half, punctures on clypeus imperceptible due to strong reticulation (Fig. 6b); punctures dense, distance between them smaller than their diameter (Fig. 6b). Punctation of pronotum double, coarse, distance between larger punctures smaller than their diameter. Punctation of elytra double, diameter of small puncture about half of diameter of large punctures; distance between large punctures, at least basally, smaller than their diameter. Epipleura smooth with fine punctures. Metatibia with outer margin nearly straight.

Male. Longer metatibial spur short, only slightly longer than metatarsomere I (Fig. 7b); spur nearly straight, broad with distinct serration (Fig. 7b). Male genitalia as in Fig. 8 h–k, median lobe in ventral view parallel-sided in most of its length.

Female. Both shiny and matt forms are known for females of H. ovatus . Shiny form agreeing well with male; matt form with whole surface densely reticulated, meshes distinctly elongate on elytra. Large punctures well visible, small punctures indistinct among reticulation. Longer tibial spur similar to that of male. Female genitalia as in Fig. 8 l–n.

Habitat.

The species inhabits various types of standing and slowly flowing water bodies with at least some vegetation. The typical habitats represent (frequently eutrophic) ponds, densely vegetated pools, ditches, oxbows or open swamps.

Distribution.

Widely distributed Palaearctic species. With the exception of the Iberian Peninsula, it occurs in most of territory of Europe and temperate Asia east to the Baikal Lake (east Siberia).