Camponotus lateralis species group

AntWiki: The Ants --- Online

Based on Radchenko 1997 and Seifert 2019.

Species

Members of the subgenus Myrmentoma

Species Identification

Seifert revised the Westpalaearctic ("the Palaearctic region west of 46°E") species of the lateralis species-group. This included nine species - C. anatolicus, C. atricolor, C. candiotes, C. heidrunvogtae, C. honaziensis, C. lateralis, C. piceus, C. rebeccae - distributed "in the whole Mediterranean area, the South Temperate Zone of Europe as well as in Asia Minor, the Cauacasus and the Middle East." Seifert's work also made clear this is a difficult group of species to identify and often requires more than a few specimens in any given sample to make accurate determinations.

Key to the West Palaearctic Camponotus lateralis species group

Group Diagnosis

The studies of Seifert and Radchenko focused on different goals. Radchenko's aim was to clarify the organization of all the Camponotus Myrmentoma species in the Asian Paleartic. In contrast, Seifert was carefully examining and measuring specimens from a smaller (but still large!) region and was restricted to the lateralis species group. Their different aims and perspectives led to their producing different diagnoses, one sparse and the other more exacting. Their work collectively leaves us with a good understanding of this species group in part of its range. Looking beyond the Westpalaearctic, much more research is needed before we have a clearer picture of the species group as a whole. One of Seifert's conclusions from his study points out the challenges such work will entail: "The fact that in the subgenus Myrmentoma three types of polymorphism – namely polymorphism of shape, pubescence and setae characters, color polymorphism and major-minor dimorphism – may superimpose within the same data set shows how cautious taxonomists have to do their work here and how misleading judgement from single specimens may be."

Radchenko's diagnosis: Propodeum flattened dorsally, with straight or concave posterior surface; thorax with or without mesopropodeal depression. Body only slightly sculptured. shining.

Seifert's diagnosis: Separated from other sympatrically occurring species groups of Camponotus by the following character combination: Comparably small size, CS ranging between 840 and 2190 μm. Dorsal area of propodeum clearly delimited laterally by strong longitudinal edges and appearing in dorsal view as a rectangle or trapezium. The median part of this area is never much higher than the lateral ones – as result a transverse section of upper propodeum is roughly rectangular with a very weakly concave, straight or weakly convex dorsal part. The overall dorsal profile of mesosoma is discontinuous, always more or less depressed between mesonotum and propodeum. In profile view, the dorsal area of propodeum is straight to convex and forms a distinct angle with the caudal declivity which falls abruptly down. Surface of gaster tergites shining, with fine transverse microripples the mean distance of which is 7–12 μm – the microripples represent the edges of a clinker-like surface structure. Pubescence hairs on gaster tergites short and never dense.

Distribution

Radchenko summarized information about the entire subgenus for the Palearctic. The species he placed in lateralis were divided into complexes that had a rough correspondence with where they occurred. He summarized it in this way: "the group lateralis has four rather isolated centers of the species diversity: Balkan~Middle Eastern (including Asia Minor), Northern~Mediterranean (chiefly S Europe), Southern-Mediterranean (chiefly N Africa), and Anteriro-Middle Asian."

Notes

Other species and subspecies have previously been placed in this group. Focusing primarily on species that Radchenko included in his study but are not in the list here, Seifert suggests three species Camponotus guanchus, Camponotus ebneri, and Camponotus staryi are likely synonyms of valid species that already belong to the species group. Radchenko included two of these species and considered the third, C. ebneri, to be a synonym of C. picea. Camponotus gestroi is excluded by Seifert due to it being inconsistent with his diagnosis. Lastly, the species Camponotus sicheli is deemed uncertain in its group affiliation due to a lack of specimens. Many decisions about species being excluded were provisional due to there being only a few specimens available for study (see Seifert 2019 for more details).

Additional Resources

References