Formicinae (Lepeletier de Saint-Fargeau)

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 : 142

Incertae sedis in the Formicinae

Genus † Kyromyrma . Comparative morphological study of † Kyromyrma (∼92 Ma, New Jersey amber; Grimaldi & Agosti, 2000) at the gross ( Figs 8L , 9K ) and fine scales reveals considerable morphological affinity to Lasius (holotype examined at AMNH). In the original description of † Kyromyrma , the authors did not address the problem of within-subfamily placement, merely noting that ‘the fossil bears an overall resemblance to Prolasius , mostly by virtue of the generalized morphology’ ( Grimaldi & Agosti, 2000, p. 13681). Our combined evidence analyses resulted in ambiguous support for the placement of † Kyromyrma , with the genus being recovered as sister to the Lasius genus group ( Figure S5 ), sister to the core Lasiini ( Figures S8 , S 9 ), sister to all Lasiini ( Figure S7 ), or sister to Formicinae exclusive of Myrmelachistini ( Fig. 4 ). Statistical support for these placements was uniformly low.

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.)

Fig. 5. Results of the BioGeoBEARS and life-history trait ancestral state estimation analyses on a chronogram pruned from the analysis of the Lasiini_w_outgroups_w_fossils_154t combined morphological and molecular dataset. Horizontal blue bars at nodes are 95% highest posterior density (HPD) intervals from the divergence dating. Coloured circles on nodes are inferred inherited biogeographic ranges, with the top half of each corresponding to the upper branch and bottom half with the lower branch; coloured circles at branch tips represent biogeographical coding for terminal; dashed lines at 60 and 30 Ma indicate the boundaries of the three BioGeoBEARS dispersal rate matrix time periods. Coloured boxes at branch tips represent presence or absence of two traits for Lasius: temporary social parasitism (black = absence, red = presence) and fungiculture (black = absence, green = presence). Stars on internal branches indicate the evolution of temporary social parasitism (red) and fungiculture (green) The figure background indicates generalized major climatological regimes during Earth’s history (Royer et al., 2004; Zachos et al., 2008; Hansen et al., 2013), while the inset globes visually represent palaeoclimate and landmass configuration modified from Scotese (1998).

Fig. 7. Some key features of the major clades of the Lasiini. (A) third abdominal tergite modified with dorsoventrally-oriented groove for reception of entire petiole (Pseudolasius breviceps); black line indicates contour of tergum and black ellipse the spiracle; (B) third abdominal tergite receiving only posterior base of petiole (Myrmecocystus mimicus); white line indicates contour of tergum, and white ellipse the spiracle; (C) frontal protuberance and effaced carinae low relative to face (P. breviceps); (D) frontal protuberance and effaced carinae raised dorsally from face (M. mimicus); (E) metapleural gland atrium grossly enlarged (Lasius subumbratus); black lines show larger size of the metapleural gland bulla (lower indicator) as compared to F, and relative to the propodeal spiracle (upper indicator) and space between the spiracle and bulla (middle portion); (F) metapleural gland atrium small (Lasius turcicus); black lines show smaller size of metapleural gland bulla as compared to E, and relative to the propodeal spiracle and space between spiracle and bulla.

Fig. 4. Results from phylogenetic analysis of the Lasiini_w_outgroups_w_fossils_154t combined morphological and molecular dataset analyzed with MrBayes using the fossilized birth-death branch length prior and the IGR clock variation prior. Fossil taxa are indicated by a dagger preceding the name. Node support values are in Bayesian posterior probability. Filled circles indicate full support. Horizontal blue bars at nodes are 95% highest posterior density (HPD) intervals.