Camponotus lateralis (Olivier, 1792)

Seifert, Bernhard, 2019, A taxonomic revision of the members of the Camponotus lateralis species group (Hymenoptera: Formicidae) from Europe, Asia Minor and Caucasia, Soil Organisms 91 (1), pp. 7-32 : 13-14

Key to the workers of the Camponotus lateralis species group in Europe, Asia Minor and Caucasus

It should be clear that a very simple key cannot achieve determinations as safe as the application of complex multivariate analyses of complete character sets. The very strong, often biphasic allometries, color polymorphism, size dimorphism as well as shape and setae polymorphism complicate the situation and do not allow simple answers to difficult questions. In order to achieve some simplicity, the key uses absolute measurements. All inputs to discriminant functions have to be in millimeters with exception of RipD where input in micrometers is required.

1a Vertex in the majority of specimens in a nest sample not completely blackish; reddish pigmentation at least in patches appearing, whole head often completely reddish brown. Microripples on dorsum of 1 st gaster tergite more widely set: RipD 8.8 – 14.1 µm. If microripples are more densely set ( C. rebeccae ), then whole vertex reddish brown ................................................................ 2

1b Vertex completely blackish. If some small parts of anterior vertex have reddish pigmentation ( C. dalmaticus ), then microripples on dorsum of 1st gaster tergite are densely set with RipD 7.59 ± 0.55..................... 6

2a Dorsal propodeal plane wide; scape base extension very strong, scape long; mesosoma wide Discriminant 21.98*P rW+ 6.89 7*ScI+ 4.015*M W– 9.25*CL0.249*SL–6.684> 2 [error 0% in 6 specimens]. Asia Minor............................................................ honaziensis

2b Dorsal propodeal plane less wide; scape base extension less strong (except C. lateralis morph 1); scape shorter; mesosoma narrower. Discriminant <2 [error 1.6 % in 191 specimens] ...................................... 3

3a Discriminant 0.712*nPr+21.46*CL–14.462*CW– 17.898*PeW+297.0*RipD –6.225> 2.3 [error 0 % in 9 specimens]. Dorsal propodeal plane in dorsal view trapezoid, in posterior part much wider than anterior; bilateral sum of setae on mesonotum and propodeum dorsal of spiracle 19.2 ± 5.7 (count also basal pits of detached setae!). Asia Minor............... anatolicus

3b Discriminant <2.3 [error 1.7 % in 182 specimens]. Dorsal propodeal plane in dorsal view posteriorly not clearly wider than anteriorly; bilateral sum of setae on mesonotum and propodeum dorsal of spiracle 8.3 ± 3.7 (count also basal pits of detached setae!)....................... 4

4a Distance of microripples on dorsum of 1st gaster tergite small, RipD 7.1–9.5 µm. Discriminant 6.107*CL– 24.624*PrL+954.7*RipD–6.81 <2.35 [error 0 % in 32 specimens]. Crete, Cyprus, Asia Minor, Syria..... rebeccae

4b Distance of microripples on dorsum of 1st gaster tergite larger, RipD 9.1–13.7 µm. Discriminant> 2.35 [error 0 % in 149 specimens]. Morphs of C. lateralis , co-occurring in 16 % of nests. North Mediterranean from Iberia to Turkey............................... 5

5a Less hairy and pubescence shorter; unilateral number of setae on dorsal plane of scape low: nSC 1.7 [0–5]; scape base extension large: ScI 1.22 [1.04–1.40]; scape and dorsal propodeal area more elongated. Discriminant 7.837*ScI–0.525*nSc+7.407*Sl+7.275* PrL–17.675> 0 [error 0 % in 86 workers]. Major workers with sinusoidally curved frontal carinae and the dorsum of propodeum only weakly convex in lateral view............. .................................................................... lateralis morph 1

5b Very hairy and with longer pubescence. Unilateral number of setae on dorsal plane of scape larger: nSC 4.29 [0–11.5]; scape base extension small: ScI 1.04 [1.00-1.10]; scape and dorsal propodeal area less elongated. Discriminant <0 [error 0 % in 64 workers]. Majors with less sinusoidally curved frontal carinae and the dorsum of propodeum strongly convex in lateral view.............................................. lateralis morph 2

6a Scape very long relative to width of mesosoma and dorsal propodeal plane. Discriminant 28.141*SL– 12.125*MW–16.724*PrW–15.683> 2.1 [error 0 % in 32 specimens]. Balkans ................. heidrunvogtae n.sp.

6b Scape clearly shorter relative to width of mesosoma and dorsal propodeal plane. Discriminant <2.1 [error 0 % in 321 specimens].................................................... 7

7a Mesonotum and propodeum with very few setae:nMn 2.0 [1–5.5], nPr 2.15 [1–4.5]; width of dorsal propodeal plane and petiole relative to CL smaller. Discriminant 0.238*nMn+0.192*nPr–13.124*CL+28.124*PrW+5.228 *PeW+2.731 <0 [error 0 % in 67 specimens]. Balkans northwest to S Switzerland............................. dalmaticus

7b Mesonotum and propodeum more hairy: nMn 4.8 ± 2.4, nPr 7.40 ± 3.4; width of dorsal propodeal plane and petiole relative to CL larger. Discriminant> 0 [error 0.8 % in 253 specimens]................................................. 8

8a Extension at scape base absent or very weak; metanotal depression very shallow. Discriminant 16.35*ScI+33.25*MGr+5.962*CW–0.146*nPr–10.773* PeW–20.913 <0 [error 1.3 % in 76 workers and 0 % in 30 nest sample means with at least 2 workers]. Pannonian Plane, Balkans, Ukraine east to Caucasus ........................................................... atricolor

8b Extension at scape base more developed; metanotal depression deeper. Discriminant> 0 [error 4.0 % in 177 workers and 0 % in 68 nest sample means of at least 2 workers]........................................... 9

9a Crete, Asia Minor, Caucasus. Discriminant 13.74*ScI+8.383*CL+8.565*SL–43.51*MGr–26.46*PrL– 19.751 <0 [error 2.5 % in 40 workers] ............. candiotes

9b South Temperate and Mediterranean Europe. Discriminant> 0 [error 2.2% in 137 workers] ...... piceus