Lasius umbratus, Nylander

Boudinot, Brendon E., Borowiec, Marek L. & Prebus, Matthew M., 2022, Phylogeny, evolution, and classification of the ant genus Lasius, the tribe Lasiini and the subfamily Formicinae (Hymenoptera: Formicidae), Systematic Entomology 47, pp. 113-151 : 139

7. Species group of umbratus (= Chthonolasius part 2/2)

( Figs 8J , 9J )

Constituent species (24): Nearctic (6): aphidicola [e], minutus Emery [e], nevadensis Cole [e], speculiventris Emery [e], subumbratus Viereck [e], vestitus Wheeler [e]; Palaearctic (18): balcanicus Seifert [e], bicornis (Foerster) [e], citrinus Emery [e], crinitus (Smith) [e], distinguendus (Emery) [e], draco Collingwood [], jensi Seifert [e], longiceps Seifert [], meridionalis (Bondroit) [e], mikir Collingwood [e], mixtus (Nylander) [e], nitidigaster Seifert [e], przewalskii Ruzsky [], rabaudi (Bondroit) [e], sabularum [e], tibialis Santschi [], umbratus * [e], viehmeyeri Stärcke [e].

Distribution: Holarctic.

Identification: Among groups of the flavus clade, most similar to those of carniolicus , flavus , and nearcticus in having relatively small eyes (vs pallitarsis ), stocky mesosomata (vs atopus ), and unreduced palpomere count (vs claviger group). Among these groups, identifiable by the following combination of traits: clypeus broad relative to head width (vs narrow, carniolicus group); eyes larger, with> 35 ommatidia, and underside of head with distinct, standing setae (vs with <35 ommatidia except L. alienoflavus and Lflavus which, along with most other flavus and nearcticus group species, lack distinct standing setae on head underside). No comprehensive key is available for the global fauna of the umbratus group; the Nearctic species are keyed in Wilson (1955) where L. aphidicola is referred to as L. umbratus , and with the addition of L. nevadensis by Cole (1956); Wilson (1955) also includes a key to some Palaearctic species, which are also partially covered by Collingwood (1982), Boer (2003) and Seifert (1988, 1990, 1997, 2018). Focused work on this species group, particularly a global key or revision, is necessary.

Note: This group corresponds to the prior subgenus Chthonolasius , with the exclusion of L. atopus . One of our molecular terminals of this group is an undescribed species near L. subumbratus .

Figures

Fig. 8. Gross phenotypic synopsis of the extant species groups of Lasius, plus two phenotypically similar fossil species; all images in full-face view; scale bars = 0.5 mm. (A) Lasius brunneus (CASENT0280440); (B) Lasius fuliginosus (CASENT0179898); (C) Lasius nr. niger (CASENT0106128); (D) Lasius nr. atopus (CASENT0234858); (E) Lasius carniolicus (CASENT0280471); (F) Lasius claviger (CASENT0103542); (G) Lasius brevicornis (CASENT0280456); (H) Lasius nearcticus (CASENT0104774); (I) Lasius pallitarsis (CASENT0005405); (J) Lasius aphidicola (CASENT0280468); (K) †Lasius schiefferdeckeri (MNHNB25217); (L) †Kyromyrma neffi (AMNH-NJ1029). (Image credits: D = the authors; AntWeb: A = Will Ericson; B = Erin Prado; C = Michael Branstetter; E, G, J = Shannon Hartman; F, H = April Nobile; I = unknown; K = Vincent Perrichot; L = Dave Grimaldi & Vincent Perrichot.)

Fig. 9. Gross phenotypic synopsis of the species groups of Lasius, plus two phenotypically similar fossil species; all images in profile view; scale bars = 1.0 mm; scale bar unavailable for K. (A) Lasius brunneus (CASENT0280440); (B) Lasius fuliginosus (CASENT0179898); (C) Lasius nr. niger (CASENT0106128); (D) Lasius nr. atopus (CASENT0234858); (E) Lasius carniolicus (CASENT0280471); (F) Lasius claviger (CASENT0103542); (G) Lasius brevicornis (CASENT0280456); (H) Lasius nearcticus (CASENT0104774); (I) Lasius pallitarsis (CASENT0005405); (J) Lasius aphidicola (CASENT0280468); (K) †Lasius schiefferdeckeri (HJF013); (L) †Kyromyrma neffi (AMNH-NJ1029). (Image credits: D = the authors; AntWeb: A = Will Ericson; B = Erin Prado; C = Michael Branstetter; E, G, J = Shannon Hartman; F, H = April Nobile; I = unknown; K = Vincent Perrichot; L = Dave Grimaldi & Vincent Perrichot.)