Cardiocondyla batesii Forel 1894

Seifert, Bernhard, 2023, A revision of the Palaearctic species of the ant genus Cardiocondyla Emery 1869 (Hymenoptera: Formicidae), Zootaxa 5274 (1), pp. 1-64 : 41

Cardiocondyla batesii Forel 1894 [type investigation]

This taxon has been described from Algeria. Investigated were 5 worker syntypes labelled “ C. Batesii , € type, Perregaux Algerie 29 III”, and 4 gyne syntypes labelled “ C. Batesii , $ type, Perregaux Algerie 29 III”, both in MHN Genève .

All material examined. Numeric phenotypical data were available in 18 samples (largely nest samples) with 37 workers. For details see supplementary information SI1, SI2. This material originated from Algeria (1 sample) , Morocco (3) and Spain (14).

Geographic range. Based on determined vouchers distributed from N Morocco (6.8°W) east to NE Algeria (6.6°E) and from S Spain north to 41.8°N. In S Spain ascending to 930 m. Unverified records presented in antmaps.org include S Morocco, Tunisia and the Balearic Islands .

Diagnosis: --Worker ( Tab. 3 , Figs. 54–57 , key; images under CASENT 0908335 in www.antweb.org). Medium-sized, CS 518 µm. Head moderately elongated, CL/CW 1.177. Postocular distance small, PoOc/CL 0.383. Scape moderately elongated, SL/CS 0.791. Eye large, EYE/CS 0.264. Median third of hind margin of head slightly concave. Frons moderately broad (FRS/CS 0.244), frontal notably converging immediately caudal of FRS level (FL/FR 1.077). Dorsal profile of promesonotum and of propodeum convex with a deep metanotal depression (MGr/ CS 3.82 %). Spines rather short and blunt, more triangular (SP/CS 0.117), their axis in profile deviating by about 43° from longitudinal axis of mesosoma, their bases rather distant (SPBA/CS 0.257). Petiole distinctly higher than wide (PeW/CS 0.282, PeH/CS 0.330); with characteristic profile, showing a short peduncle, a rather straight to weakly convex anterior face and an ample node with the anterior slope less steep than the caudal slope (about 60° respectively 75° relative to ventral profile). Petiole in dorsal view with elongated node that gradually merges with the anterior peduncle. Postpetiole wide (PpW/CS 0.533, PpW /PeW 1.89, PpH/CS 0.286), in dorsal view suggestively heard-shaped, with a concave anterior margin and convex sides; postpetiolar sternite completely flat. Median and paramedian clypeus smooth; lateral clypeus with 1–2 longitudinal rugulae. Dorsal head almost without longitudinal sculpture; weak longitudinal carinulae are present on and posterior of the frontal laminae. Vertex with very shallow foveolae of 15–16 µm diameter; the margins of foveolae often breached by microrugulae running partially or entirely through the foveolae; the interspaces on average wider than foveolar diameter, shiny and with fragments of a very delicate microreticulum ( Fig. 57 ). Dorsal mesosoma shiny, but finely microreticulate; meso- and metapleurae finely rugulose-reticulate. Waist segments very shiny, with barely visible microreticulum. Pubescence on gaster tergites moderately long and dense, PLG/CS 5.55 %, sqPDG 4.84. The typical color pattern is bicolored: dorsal head medium brown, mesosoma and waist light orange brown, gaster dark brown. This distinct color contrast may be lost in rarely occurring specimens with darker brown mesosoma.

Taxonomic comments and clustering results. The only species with sympatric occurrence related to Cardiocondyla batesii is C. nigra . C. batesii is strongly separable on the worker individual level by a PCA considering all the 14 morphometric characters shown in Tab. 3 as available for all 132 individuals ( Fig. 112 ). All classifications, including the single batesii worker displaced by the PCA, are confirmed with p> 0.97 by a LOOCV-LDA reduced to the 10 characters CS, CL/CW, SL/CS, PoOc/CS, dFOV, PeW/CS, PeH/CS, PpH/CS, sqPDG, and PLG/CS in order to avoid character overfitting. The type series of C. nigra , C. torretassoi and C. bicoronata are allocated to the nigra cluster with p = 1.000 and the type series of C. batesii with p = 1.000 to the batesii cluster. A simpler way for a perfect separation, using six primary measurements given in mm, is offered by a linear discriminant

D(6) = 63.22*CL-63.18*PoOc+55.89*SL+64.64*PeW-184.93*PeH-93.82*PpH-11.19.

C. batesii D(6) -2.459 ± 0.892 [-4.11, -0.53] n=37

C. nigra D(6) 2.786 ± 1.038 [0.53, 5.20] n=95

Allopatric species with similarities to C. batesii are C. semirubra from Asia Minor and C. kushanica from Afghanistan. Non-overlapping morphometric data and structural differences provide arguments to treat these taxa as heterospecific in addition to the geographic argument (see the sections treating these species, p. 43, p. 45).

Biology. The biology of populations in southern Spain was investigated by Heinze et al. (2002) and Schrempf et al. (2005): Nests were found in cavities in the soil down to a depth of more than 1 m in very sunny and dry places. Colony density was high, with up to one nest per square meter. Nest populations contained 10– 120 workers, were strictly monogynous and could contain 1–3 ergatoid males. Winged males were not observed. Workers never tolerated the presence of more than one inseminated, fertile gyne. Gynes mated in the nest in autumn, with mean mating frequencies of 1.52 ± 0.65 [1–3], and dispersed on foot to found their own colonies in spring. Gynes were dimorphic in mesosoma size which was correlated with wing length (brachyptery vs. macroptery). Yet, flight musculature was not sufficiently developed in both brachy- and macropterous gynes to allow flying. This reduced dispersal capacity explained the high inbreeding coefficient and the close genetic relatedness between queens and their mates and it was suggested that 83% of all matings were between brothers and sisters. As expected from local mate competition theory, sex ratios were extremely female biased, with more than 85% of all sexuals produced being young gynes.

Figures

FIGURES 54–57. Cardiocondyla batesii; Fig. 54: head in dorsal view; Fig. 55: lateral view; Fig. 56: dorsal view; Fig. 57: head surface between inner eye margin and paramedian vertex. Spain: Padul-4.5 km WNW, 2001.04.18

FIGURES 109–113. Cardiocondyla obscurior; Fig. 109: head in dorsal view; Fig. 110: lateral view; Fig. 111: dorsal view; Fig. 112: head surface between inner eye margin and paramedian vertex; Fig. 113: frontolateral aspect of waist segments. Galapagos: Santa Cruz, 2012.11.19