Stilbum wesmaeli Dahlbom, 1845

Rosa, Paolo & Vardal, Hege, 2015, An annotated catalogue of the types of Chrysididae (Hymenoptera) at the Swedish Museum of Natural History, Stockholm, with brief historical notes, ZooKeys 495, pp. 79-132 : 115-116

Stilbum wesmaeli Dahlbom, 1845 Plate 32

Stilbum Wesmaeli : Dahlbom 1845: 16.

Type locality.

Greece: Rhodes.

Holotype ♂.

[Rhodus] [Hedb.] [NHRS-HEVA000001129].

Remarks.

Dahlbom (1845) described Stilbum wesmaeli without any note on the type series. More information can be found in his monographical work ( Dahlbom 1854: 359): " Habitat in insula Rhodo; specimen unicum e Mus. Reg. Acad. Scient. Stockholm. communicavit Dom. Boheman.". Currently there are three specimens in the collection collected on Rhodes by Hedenborg. Only one has a different printed label [Hedb.] [NHRS-HEVA000001129] instead of [Hedenb.] [NHRS-HEVA000001137-1138]. Hedenborg visited Rhodes more than once, and these three specimens should have been collected in two different journeys. We consider as holotype the one with a different label (NHRS-HEVA000001129).

After Dahlbom (1854), all the most important authors considered Stilbum wesmaeli as synonym of Stilbum cyanurum (Forster, 1771) ( Mocsáry 1889: 190; Dalla Torre 1892: 38; Bishoff 1913: 26; Trautmann 1927: 80; Linsenmaier 1951: 107). However, it was not even mentioned by Mader (1933) and Zimmermann (1937) in their revisions of the genus Stilbum . In his major revisions, Linsenmaier (1959: 181 and 1968: 123) used the name Stilbum calens ssp. subcalens Mader, 1933 (invalid name because described as aberratio) in place of Stilbum wesmaeli for the corresponding subspecies distributed in the Mediterranean basin (Dalmatia, Balcan Contries, Rhodes, Persia, southern Switzerland (Misox), southern France, Spanien, northern Africa ( Linsenmaier 1959) and Lebanon ( Linsenmaier 1968)).

In the last publications, Linsenmaier (1997a: 287, 1997b: 134, 1999: 254) used Stilbum calens ssp. wesmaeli Dahlbom as the oldest name for this species, synonymizing Stilbum subcalens and Stilbum macedonicum Trautmann, 1926 with Stilbum calens ssp. wesmaeli . Linsenmaier (1959) treated the invalid name subcalens as subspecies of Stilbum calens , and thus made this name available as species-group name (ICZN 1999, article 45.6.3.). As Linsenmaier was the first author to make the name available, he should be considered as the author of Stilbum subcalens (ICZN 1999, article 50.3.1.).

The type and the other specimens of Stilbum wesmaeli in NHRS are not related to Stilbum calens (Fabricius), but belong to a different population of Stilbum cyanurum (Forster) probably endemic to the island. Dahlbom (1845, 1854) descriptions are clear and this species is easily identifiable by the typical shape of the metanotal protrusion, which is deeply bilobed (" postscutelli processus emarginatus "). All the specimens from Rhodes show this special feature, and for this reason we consider this isolated population as a possible valid subspecies.

Current status.

Stilbum cyanurum ssp. wesmaeli (Dahlbom, 1845).