Corresponding author: Martin Fikáček (
Academic editor: Jes Rust
This study focuses on the fossil beetles assigned previously to the family
In his study of the insects from the Tertiary outcrop of Brunstatt (Alsace, France),
For this study, we have re-examined the specimens from the locality of Kleinkems studied previously by
The Tertiary outcrops of Brunstatt and Kleinkems were located in the south-west of central Europe and no longer exist today. Brunstatt was situated south of the city of Mulhouse in France (47°41'N, 7°31'E); Kleinkems was situated in Germany (47°43'N, 7°19'E) northwest of the city of Basel (Switzerland), about 16 km from Brunstatt. Several hundred fossils in total were collected at these localities (
According to the reconstruction of the sedimentation history, the limnic sediments of Brunstatt and Kleinkems were deposited on the shore of a very large shallow saline lake (with an area of several hundred square kilometres) with episodical intrusion of fresh water (
It seems very likely that the sediments of Brunstatt and nearby Kleinkems are nearly identical in age and genesis.
Only the fossils from the locality of Kleinkems mentioned by
Fossils were examined using the Olympus SZ61 binocular microscope. Photographs were taken using the Canon MP-E 65 mm macro lens attached to the Canon EOS 550D camera. Drawings were traced from photographs. Abbreviations used in descriptions are:
Fossils whose family placement and hence also generic placement remains unclear are cited using the original combination of the name, placing the respective genus name in quotation marks.
Neotype, by present designation (NHMB): R91 (imprint) + R74 (counter-imprint) from the locality of Kleinkems (SW Germany, ca. Eocene-Oligocene boundary): fossil of the whole beetle in dorsal view, head, pronotum and elytra almost completely preserved; appendages missing.
Body oblong-oval, broadest in basal third of elytra. Head relatively broad; compound eyes large, not exceeding body outline; clypeus rounded. Pronotum broadest between posterior angles, lateral margins regularly, moderately curved. Mesoscutellar shield well preserved, broadly triangular. Base of elytra as broad as pronotal base; lateral margins of elytra moderately curved. Only mesocoxae, part of metathoracic anepisternum, and probably part of apical abdominal ventrite perceptible from ventral part of body (
Surface sculpture. Pronotum with distinct longitudinal median impression, and poorly perceptible short longitudinal striolae on disc. Elytra with 12 moderately impressed longitudinal striae.
Measurements. TL: 6.3 mm, TL-h: 5.6 mm, TW: 3.2 mm. EL: 5.2 mm.
Theneotype corresponds well with the original description and drawings by
The reasons provided above together with the same age, geological origin and geographical proximity of both outcrops (Brunnstatt and Kleinkems) provide strong support for the conspecificity of both specimens mentioned by
The preserved characters of the ventral morphology, i.e. the narrow metathoracic anepisternum arising from the median coxal cavity and the anepisterno-metaventral suture directed lateroposteriad correspond closely with the ventral morphology of the
Altogether five species of fossil
List of fossil species of the genus
Species | Period | Body length | Number of elytral striae | Species group ( |
---|---|---|---|---|
|
Eocene | 5.0 mm | 19 discal | |
|
Eocene- Oligocene boundary | 6.3–6.5 mm | 12 discal | |
|
Miocene | 6.1–6.5 mm | 10 discal + 1 submarginal | |
|
Miocene | 5.5–5.6 mm | 6 discal + 1 submarginal | |
|
Miocene | 3.8–4.4 mm | 11 discal + 1 submarginal | |
|
Miocene | 5.1 mm | 11 discal |
As in the case of
Based on the original drawing by
Specimen no. R707 from Kleinkems does not bear any synapomorphy of the
Based on the original drawing by
Based on the drawing by
We are indebted to W. Etter (Naturhistorisches Museum, Basel) for the opportunity to re-examine the specimens studied by Théobald (1937), to J. C. Horrenberger (École et Observatoire de la Terre, Strasbourg) and V. Püthz (Max-Planck-Institut für Limnologie, Schlitz/Hessen) for information about the type specimens by Förster (1891), to T. Wappler (University of Bonn) for help with geological and paleontological literature, and to M. Lambertz and C. Carrington for proof reading the English text.
The study was supported by grant KJB301110901 from the Czech Academy of Sciences (GAAV), grant MK 00002327201 from the Ministry of Culture of the Czech Republic and grant MSM 0021620828 from the Ministry of Education of the Czech Republic.