Leptogenys crudelis

Identification
Lattke (2011) - Eye flat, its length almost one-fourth length of lateral cephalic margin; scape surpasses posterior margin by more than one-third its length. Anterior margin of node in dorsal view less than one-fourth width of posterior margin; constriction between third and fourth abdominal segments well marked.

This species is sympatric with Leptogenys iheringi in Bahia, and can be easily confused with it. L. crudelis has a thicker node along the anterior part, with a convex cross-section, in contrast with the thin node of L. iheringi in dorsal view, with vertical lateral sides, and more flattened top. The anterior margin in dorsal view is less than one-fourth the width of the posterior margin. The node of L. iheringi in lateral view has a continuously curved anterodorsal margin, and the eye in L. iheringi is weakly convex, whilst it is totally flat in L. crudelis. The scape surpasses the posterior cephalic margin by less than one-third its length in L. iheringi and the internal and masticatory mandibular margins meet through a rounded angle. The Paraná specimens have very parallel mandibles and a more pronounced mandibular angle, plus darker coloration.

Distribution
This taxon was described from Brazil. It is known from southeastern Brazil.

Castes
Male unknown.

Nomenclature

 *  crudelis. Ponera crudelis Smith, F. 1858b: 97 (w.) BRAZIL. Lattke, 2011: 152 (q.). Combination in Lobopelta: Mayr, 1886c: 358; in Leptogenys: Emery, 1911d: 105. Senior synonym of rubicunda: Borgmeier, 1932b: 485.
 * rubicunda. Leptogenys (Lobopelta) rubicunda Borgmeier, 1930: 28, pl. 4, figs. 13, 14, 17, 21, 25, 26 (w.q.) BRAZIL. Junior synonym of crudelis: Borgmeier, 1932b: 485.

Worker
Lattke (2011) - Metrics (n = 5): HL 1.21-1.34; HW 0.76-0.81; ML 0.63-0.73; EL 0.18-0.25; SL 1.19-1.39; PW 0.68-0.71; WL 1.85-2.02; PH 0.68-0.73; PL 0.68-0.73; DPW 0.43-0.48 mm. CI 0.60-0.64; MI 0.83-0.97; OI 0.23-0.31; SI 1.56-1.72; LPI 0.93-1.00; DPI 0.59-0.68.

Head elongate, rectangular in full-face view, widest anterad than posterad, lateral margin broadly curved, curvature sharpest posterad; posterior cephalic margin straight with well-defined vertexal carina. Anterior clypeal process triangular, gradually tapering to blunt point; eye length almost one-fourth of lateral cephalic margin; eye flat, ocular mid-point closer to mid-length of cephalic lateral margin than to mandibular insertion. Mandibular dorsal surface smooth and shining, basal and external margins subparallel, masticatory margin edentate; basal angle blunt; PF: 4,3. Cephalic dorsum mostly smooth and shining; scape smooth and shining with abundant inclined pilosity; scape surpasses cephalic posterior margin by more than one-third its length; third antennal segment longer than either second or fourth segment, fourth antennal segment more than half as long as third segment; funicular segments subcylindrical, without sharp constriction between each.

Promesonotal dorsal margin forms more or less single convexity in lateral view, metanotal groove deep and broad, propodeal dorsal margin broadly convex, declivity sharply convex, propodeal lobes at spiracle height, bluntly triangular; mesosoma mostly smooth and shining; mesopleuron with carina along anterior margin and sparse low rugulae posteriorly; metapleural rugulose towards bulla; mesopleural suture impressed at level of metathoracic spiracle; mesometapleural suture well impressed, scrobiculate. Mesonotum wider than long in dorsal view, anterior margin convex, posterior margin straight to weakly concave. Propodeal spiracle elongate and oval, vertical; declivity with parallel transverse striae. Body smooth and shining with no appressed pubescence, with scattered subdecumbent to suberect fine golden hairs, scape with abundant decumbent pilosity.

Petiole roughly subquadrate in lateral view, with semi-vertical anterior and posterior margins, both tending to converge dorsad; dorsal margin convex, higher posterad than anterad, anteroventral process quadrate, with anterior and posterior angles. Posterior face of node smooth and shining, sides curving on to posterior face. Node in dorsal view triangular, slightly longer than wide; anterior margin convex, less than half as wide as posterior margin; lateral and posterior margins straight, joined by curves; node smooth and shining. Gaster with anterior margin almost vertical in lateral view, very broadly convex, curving strongly at a level 3/4 height of node, smooth and shining throughout; constriction between third and fourth abdominal segments well marked. Body dark brown; legs, mandible, and clypeus slightly lighter colored.

Queen
Lattke (2011) - Metrics: HL 1.47; HW 0.96; ML 0.78; EL 0.35; SL 1.47; PW 0.83; WL 2.07; PH 0.91; PL 0.71; DPW 0.68 mm. CI 0.66; MI 0.82; OI 0.37; SI 1.53; LPI 1.29; DPI 0.96. Queen with usual differences from workers; three well-developed ocelli present.

Type Material
Lattke (2011):

Syntype workers: Brazil, Constancia, i.1857 (H. Clark) [examined].

Leptogenys (Lobopelta) rubicunda. Syntype workers: Brazil, Rio de Janeiro, Petropolis, ix.1928 (A. Wiltuschnig) [examined].

The worker syntype in the Hope Museum is on a card mount, along with a cocoon. The scape is partially glued to the card, thus the distance it surpasses the posterior cephalic border can not be totally gauged. The data label states: Constancia, Jan 1857, H. Clark. Type Hym 933. Ponera crudelis. The two syntype workers in BMNH bear the same locality and collector data as the OXUM worker but carry a data disk that is absent from the Oxford specimen, “57/43”. The BMNH Accessions Register for 1857, no. 43 states, “May 16. Brazil. Presented by the Rev. Hamlet Clark. Collected at Constancia, Petropolis and other localities in the province of Rio. The localities are attached to each specimen”. A worker in the MZSP is glued to a similar card as the type, and is also similar in the way the legs and antennae are spread. It bears a label stating Brazil, Col Smith, plus an additional label stating “compared with Leptogenys crudelis type, H. Donisthorpe det. 25.vii.1932”. It also has another determination label by Borgmeier. Examination of the L. rubicunda types revealed no significant differences from L. crudelis, as Borgmeier (1932) realised when he studied the L. crudelis type, confirming what he suspected upon describing L. rubicunda.

Additional References

 * [[Media:Borgmeier 1932b.pdf|Borgmeier, T. 1932b. Leptogenys crudelis Fr. Smith, 1858 (Hym. Formicidae). Rev. Entomol. (Rio J.) 2: 485 PDF]]
 * Lattke, J.E. 2011. Revision of the New World species of the genus Leptogenys Roger (Insecta: Hymenoptera: Formicidae: Ponerinae). Arthropod Systematics & Phylogeny 69:127-264.