Bembidion succini Giebel

Schmidt, Joachim & Michalik, Peter, 2017, The ground beetle genus Bembidion Latreille in Baltic amber: Review of preserved specimens and first 3 D reconstruction of endophallic structures using X-ray microscopy (Coleoptera, Carabidae, Bembidiini), ZooKeys 662, pp. 101-126 : 102

Bembidion succini Giebel

Bembidium succini Giebel, 1856: 64.

Remarks on description and type material.

B. succini was described from Baltic amber and it is the first fossil species described in this genus to species level. Although it was mentioned in catalogues of Baltic amber fossils ( Spahr 1981, Keilbach 1982, Alekseev 2013) subsequent researchers did not discuss the taxonomic position of this species.

The original description of B. succini , however, does not provide information to which genus of ground beetles this species actually belongs. Giebel (1856) noted that he was unable to recognize the diagnostic characters of the genus as well as of the whole Bembidiini tribe in this species. Mouth parts, the ventral side of body, elytral apex, and the legs were not visible to him, or he did not describe relevant characters of these body parts. The placement of this fossil in the genus Bembidion was solely based on the similarity of the external shape and proportions compared to some extant Central European species of the subgenus Ocydromus Clairville, 1806. The following citation represent the complete description provided by Giebel (1856):

"Das einzige Bernsteinexemplar der Leipziger Universitätssammlung ist kaum eine Linie lang und nähert sich zunächst den lebenden B. brunnicorne , B. perplexum , ist jedoch noch schmäler und gestreckter als diese, das Halsschild mit weniger convexen Seiten, die Flügeldecken mit feinen Punktstreifen, das ganze Tierchen hellgrün. Leider umgibt eine Blase das Thierchen so, daß ich weder die Beine noch die Palpen deutlich erkennen kann und nur aus den übrigen Formverhältnissen auf die Gattung Bembidium schließe“ ( Giebel 1856: 64).

Based on the few character states presented in this description it cannot be excluded that the name B. succini is given to a tiny (body length not even 2.3 mm) representative of the subtribe Tachyina or even to an Eocene species of a non- Bembidiini lineage.

Unfortunately, the taxonomic position of B. succini has remained ambiguous since all Baltic amber fossils of the Christian Gottfried Giebel collection are missing today. About 150 years ago, the fossil collection of Giebel was completely moved from the palaeontological collections of the Leipzig University to the University of Halle where it is now part of the geoscientific collections of the Institute of Geosciences and Geography. In 1973 parts of this collection were loaned to the Bulgarian Academy of Sciences for further study and were probably returned to Halle in 1998, however, details of the transfer of the material as well as its current location are unknown ( Henniger 2011). It is also unknown whether the loaned material contained amber fossils. In any event, nowadays not a single amber fossil ex collectio Giebel exists in the University of Halle (Norbert Hauschke, Institute of Geosciences and Geography, University of Halle, pers. comm.)! Thus, at the current state of knowledge it remains unclear whether the amber fossils of the Giebel collection are fully lost or only stored well hidden, e.g., within sealed containers in the stack-rooms of the University of Halle ( Henniger 2011).