Camponotus lateralis var. rectus Forel 1892

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 : 23-24

Camponotus lateralis var. rectus Forel 1892 [New

Synonym]

[unavailable name, junior primary homonym of Camponotus lubbocki rectus Forel 1891 ] There is no material in the MHN Genève or NHM Basel collection that can be reliably identified as type material. Forel gave as sampling sites the Bulgarian Black Sea towns ‘Anchialo’ (today named Pomorje) and ‘Sozopolis’ (today Sozopol) and Forel’s description of the mesosomal shape strongly suggests a synonymy with C. atricolor . This view is supported by the fact that C. atricolor is by far the most abundant of the black species along the western coast of Black Sea. Four investigated workers of topotypical material from Sozopolis in the Forel collection in MHN Genève (possibly types which Forel missed to designate) are allocated to C. atricolor with a mean posterior probability of p = 0.9975 if run as wild-card in a 5-class LDA considering the five black species given in Tab. 3 .

All material examined. A total of 36 nest samples with 77 workers were subject to NUMOBAT investigation.

AUSTRIA: Junger Berg , 1999.06.05 [47.960, 16.778, 214] ; Zurndorf (leg. Franz), pre 1960.xx.xx [47.961, 16.991, 159] ; Gumpoldskirchen- 2 km NNE, 1909.06.26 [48.062, 16.292, 350] ; Göttlesbrunn, Oberer Haidenberg, 1966.xx.xx [48.080, 16.733, 245] . BULGARIA: Arkutino, 1978.08.01 [42.351, 27.707, 8] ; Burgas- 7 km S, 2003.09.30, samples No 710, 711, 716, 718 [42.451, 27.469, 1] ; Chernomorez, 2006.07.30 [42.450, 27.650, 8] ; Melnik, 1982.08.28 [41.524, 23.401, 470] ; Melnik, 1982.08.30 [41.529, 23.393, 394] ; Melnik, 1982.09.01 [41.524, 23.401, 394] ; Nessebar, 1974.06.20 [42.66, 27.71, 10] ; Nessebar, 1974.07.20 [42.66, 27.71, 10] ; Ropotamo, 1982.09.18 [42.302, 27.728, 9] ; Rozen- 4 km N, 1982.08.26 [41.567, 23.449, 1180] ; Sofia: Lülingebirge, 1909.05.xx [42.66, 23.12, 1000] ; Sozopol, 1982.09.20 [42.411, 27.694, 30] ; Sozopolis (= Sozopol) (leg. Forel), 1891.08.xx [42.41, 27.69, 30] ; Srebarna, 1989.07.14 [44.09, 27.06, 35] ; Tirnovo, 1920.xx.xx [43.09, 25.66, 325] . CZECHIA: Kurdejov- 1.2 km NW, 2008.05.10 [48.966, 16.751, 322] . GEORGIA: Tbilissi-N, 1985.07.21 [41.78, 44.77, 600] ; Tbilissi, 1985.07.25 [41.70, 44.80, 600] . GREECE: Chania: Pilion, 42.41, 27.69, 30] ; Holomontas, Stagira, 2009.09.03 [40.517, 23.733, 539] ; Mazedonien Expedition, 1917/1918.xx.xx [40.0, 21.0, 500, guess] ; Nestos-Delta, 2009.xx.xx [40.85, 24.87, 2] ; Paralia Katerini, 2012.08.28 /29 [40.264, 22.596, 5] . HUNGARY: Balatonakali, 1987.06.xx [46.893, 17.523, 160] ; Budapest-Ujpest, 1909.xx.xx [47.565, 19.092, 110] . ROMANIA: Mehadia, 1909.06.10 [44.90, 22.36, 166] . RUSSIA: Rossia Meridionale, pre 1849.xx.xx [46, 40, 70; guess] . UKRAINE: Crimea: Kamenskoje , 2010.09.xx [45.279, 35.523, 6] ; Krim (= Crimea), 1900.xx.xx [45.18, 34.28, 200; guess] .

Geographic range. Steppe zones of Caucasian lowlands, the south of European Russia and the Ukraine, Balkans, Hungary, E Austria and S Moravia (here the northernmost confirmed site at 49.0°N). There is a strong range overlap with C. piceus on the Balkans and some overlap with C. candiotes in the Caucasus.

Diagnosis ( Tab. 3 , see key): Differential characters of C. atricolor against other blackish species of the group, which are detectable by subjective eye inspection, are the shallow, sometimes nearly absent, metanotal depression, the roughly linear dorsal mesosomal profile and the missing extension of large scape diameter near to its base. However, due the negative allometry of scape base extension, this structure may be missing in large workers of the other four species. A minor worker is depicted in AntWeb.org under CASENT0179869 and a major worker under CASENT0179870.

Biology. See Seifert (2018).

Comments. C. atricolor has been raised to species level by Seifert (1996) and Seifert (2007) but this view did not receive much appreciation by other myrmecologists. It is apparent that C. atricolor , C. piceus and C. candiotes are closely related but only the latter two represent truly cryptic species. The exploratory data analyses NC-part. hclust, NC-part.kmeans and NC-Ward provide a clear separation of C. atricolor from the cluster of siblings formed by C. piceus and C. candiotes . Considering CS and all 12 RAV-corrected shape and seta characters, the error rate on the K = 2 level ( atricolor vs. piceus + candiotes ) in 124 examined samples is 0% in NC-part.hclust, 2.4 % in NC-part.kmeans and 0 % in NC-Ward ( Fig. 12 ). The three samples misclassified by NC-part.kmeans were rectified by the controlling LDA if run as wild-cards. The mean error rate of the three exploratory data analyses of 0.8% is clearly below the 4 % threshold recommended by the Pragmatic Species Concept ( Seifert 2014). Thus we have a strong justification for the species status of C. atricolor (for the relations between C. candiotes and C. piceus see there).

This clear result on the nest sample level is confirmed by analyses on individual level. The classification error by a LDA considering the five blackish species given in Tab. 3 is only 1.3 % in 77 worker individuals of C. atricolor and 0.8 % in 357 individuals of all five species. The corresponding errors in a leave-one-out cross-validation LDA are 1.3 % and 1.4 % respectively.

Figures

Figure 12. Classification of Camponotus atricolor (black bars) against the cryptic species pair C. piceus + C. candiotes (red bars) in three different exploratory data analyses using body size and the full (unselected) set of RAV-corrected shape and setae characters. The error relative to the final species hypothesis is 0% in NC-Ward, 0% in NC-part.hclust and 2.4% in NC-part.kmeans.