Lasius brunneus (Latreille 1798)

Seifert, Bernhard, 2020, A taxonomic revision of the Palaearctic members of the subgenus Lasius s. str. (Hymenoptera, Formicidae), Soil Organisms 92 (1), pp. 15-86 : 47

4.4.1 Lasius brunneus (Latreille 1798)

Formica brunnea Latreille 1798 [conception of Mayr (1861) and neotype fixation] Both the original description and that of Latreille (1802) do not allow a species identification. The locus typicus is Brive/ France. The first unambiguous description was presented by Mayr (1861) that has been adopted by most of the European authors since then. A neotype is fixed herewith in three worker specimens collected near Brive, labelled ”FRA: 44.9125°N, 1.4769°E, Souillac– 1.7 km N, 120 m, tree row, leg. Galkowski 2008.09.07 “ and ” Neotype (top) Lasius brunneus (Latreille 1798) des. Seifert 2019“; depository: SMN Görlitz.

Lasius pallidus (Latreille 1798)

Formica pallida Latreille 1798 [indirect indication]

This taxon is not identifiable from data in the original

description. Yet, as the synonymization with Lasius

brunneus was established by Latreille himself (Latreille

1802), I follow his decision.

Lasius timidus (Foerster 1850)

Formica timida Foerster 1850 [original description]

This taxon was described from near Aachen / Germany.

The reported morphology (coloration, length of frontal

line, pilosity) in combination with zoogeography

strongly suggests a synonymy with L. brunneus .

Lasius alienobrunneus Forel 1874

Lasius niger var. alienobrunneus Forel 1874

[ type specimens]

Forel did not mention a locus typicus. Five workers

stored in MHN Genéve, labelled as ” Typus “ and ”L .

alienobrunneus For. / Vaux“ do not show any notable

deviation from the normal morphology of L. brunneus

both by NUMOBAT data and subjective impression

(pictures in www.antweb.org under CASENT0911044).

All material examined. A total of 32 nest samples with 67 workers were subject to NUMOBAT investigation. These originated from Austria (1 sample), Bulgaria (1), England (1), France (3), Germany (11), Greece (1), Italy (1), Spain (2), Sweden (1), Switzerland (2), and Turkey (8). For details see supplementary information SI1 .

Geographic range. Eurocaucasian , submeridional and temperate. From S England and Iberia across Central Europe , the Apennine and the Balkans to Asia Minor and the Caucasus. In Scandinavia north to 60°N, absent from Finland. In N Tyrol ascending to 1410 m and in Anatolia at 37°N to 2000 m .

Diagnosis (Tab. 1, Figs. 1 –2; images in www.antWeb. org with specimen identifiers CASENT0172717, CASENT0172745, CASENT0172746, CASENT0179886, CASENT0179917, CASENT0179917, CASENT0911044:

The species is rather easily identified by a combination

of short scape (SL/CS 900 0.874), broad head (CL/CW 900 1.041), reduced setae numbers on all body parts (nOcc 900 2.0, nGen 900 0.1, nGu 900 1.3, nSC 900 0.0, nHT 900 0.1, nSt 900 1.1) a very smooth pubescence surface on scape and tibiae, and reduced number of mandibular dents (MaDe 900 7.06). The dorsal and posterior profile of propodeum are linear and form a distinct, obtuse angle. The petiole is in anterocaudal view rather rectangular or slightly converging dorsad but typically with straight sides and forming a sharp, weakly emarginate dorsal crest. A typical coloration of medium-sized to large specimens is mesosoma, petiole and appendages light yellowish brown, head a little darker bronze brown and gaster dark to blackish brown. However, small workers from initial colonies may show a homogenously dark coloration as seen in L. lasioides or L. neglectus but can easily be separated by RAV-corrected NUMOBAT data.

Biology. See Seifert (2018).

Comments. For separation from the eastern sister species L. silvaticus sp. nov. and L. himalayanus see there and Tab. 1.

Figures

Figs. 1 and 2: Lasius brunneus; neotype