Hylomyrma sagax Kempf, 1973

Ulysséa, Mônica Antunes, 2021, Taxonomic revision of the Neotropical ant genus Hylomyrma Forel, 1912 (Hymenoptera: Formicidae: Myrmicinae), with the description of fourteen new species, Zootaxa 5055 (1), pp. 1-137 : 109-112

Hylomyrma sagax Kempf, 1973

Figures 69 , 70 , 83 (map)

Hylomyrma sagax Kempf, 1973: 249 (W, Q). Holotype: COLOMBIA: Amaz.[Amazonas]: 7km NW Letícia , 20–25 Feb 1972, #230, forest litter, berlesate, S. & J. Peck [leg.] (1W) (MCZ35422) [MCZC] [examined]. Paratypes: same data as holotype (2W 1Q) (MCZ35422) [MCZC] [examined]; (2W) (ANTWEB-1008993 MZSP67450 ) [MZSP] [examined]; (1W) (MZHY212) [MZSP] [examined].

Diagnosis. Vermicular striae on head dorsum and mesosoma; propodeal spine long; dorsal margin of petiole continuous, convex; petiole ventral surface smooth; longitudinal and anastomosed striae on postpetiole and tergum of first gastral segment; subpostpetiolar process prominent, convex; profemur almost entirely striate, apical region of posterior surface smooth; protibia entirely striate; long striae on tergum of first gastral segment.

Redescription. WORKER (n=4) ( Fig. 69A–C ): HL 1.02 (1.02–1.10); HW 0.98 (0.98–1.03); ML 0.68 (0.68–0.72); SL 0.74 (0.74–0.80); MOD 0.27 (0.26–0.28); PNW 0.72 (0.72–0.78); WL 1.38 (1.38–1.50); PSL 0.42 (0.42–0.46); PL 0.66 (0.64–0.68); PW 0.26 (0.26–0.28); PPL 0.40 (0.36–0.42); PPW 0.37 (0.37–0.40); GL 1.10 (1.10–1.28); TL 5.24 (5.24–5.70); CI 96.08 (93.63–97.11); SI 75.51 (75.51–79.20); OI 27.55 (26.53–27.72). Large-sized. Shiny integument. Dark brown body, lighter leg. Thin and unbranched setae, long to midsized, erect to subdecumbent.

Head subquadrate; posterior margin slightly concave at middle. Mandible masticatory margin with 5 teeth. Anterior margin of clypeus slightly concave medially, with a pair of large and blunt teeth laterally; median area of clypeus with 10 irregular to regular, longitudinal striae converging to a point on the anterior margin, interspaces distinguishable. Frontal triangle with 1 sagittal stria. Short scape, not reaching head posterior margin; apical antennomere shorter than previous 3 antennomeres together. Frontal carina slightly concave posterior to antennal socket. Eye drop-shaped, midsized, larger diameter with 13 ommatidia. Head dorsum with vermicular to vermiculatedareolated striae, divergent and anastomosed towards posterior margin, interspaces between striae smooth. Striae on head lateral and laterodorsal regions converge to mandible insertion; longitudinal, irregular to vermicular striae on head lateral; longitudinal striae posteriorly anastomosed on lateral and lateroventral regions; gena striate, around 4–6 regular and semicircular striae circumscribe the torulus, not reaching eye margin. Interspaces between striae on head ventral surface distinguishable.

Vermicular striae of uniform thickness on mesosoma dorsum, transverse on pronotum anterior region and propodeum (DV), longitudinal on other parts, interspaces smooth. Promesonotal junction and metanotal groove indistinct. Transverse carina well-marked. Dorsal margin of mesosoma continuous, convex. Propodeal lobe bidentate, dorsal tooth slightly longer and more acute than the shorter and blunt ventral tooth; dorsal tooth length 1 / 2 of propodeal spine length. Propodeal spine long, straight (LV), divergent (DV), sculptured on base. Thin striae of uniform thickness on procoxa; irregular and transverse striae on C2 and C3. Irregular to regular transverse striae on profemur anterior and posterior surfaces, apical region smooth; ventral surface smooth. Protibia entirely striate.

Dorsal margin of petiole continuous, convex; mostly covered with irregular to vermicular striae; ventral surface smooth. Longitudinal and anastomosed striae on postpetiole; subpostpetiolar process striae restricted to lateral region, midbasal region smooth; subpostpetiolar process prominent, convex.

First gastral segment striation similar to postpetiole striae; long striae on tergum, length similar to postpetiole length; sternite striation covering the laterobasal region.

QUEEN (n=1, paratype) ( Fig. 70A–C ): HL 1.08; HW 1; ML 0.68; SL 0.78; MOD 0.31; PNW 0.90; WL 1.64; PSL 0.44; PL 0.74; PW 0.30; PPL 0.46; PPW 0.44; GL 1.32; TL 5.92; CI 92.60; SI 78; OI 31. Large-sized. Color, pilosity, and some sculpture characters shared with conspecific workers, only slightly larger. Larger diameter of eye with 16 ommatidia. Longitudinal, irregular, slightly anastomosed striae on scutum going from an anterior central point towards transcutal suture, interspaces distinguishable. Longitudinal striae with interspaces distinguishable on anepisternum and katepisternum, mostly irregular and anastomosed on anepisternum and regular on katepisternum. Axilla with mostly anastomosed striae, striation inclinated to anteroposterior body axis. Scutoscutellar sulcus inconspicuous. Mostly vermicular striae on scutellum. Transverse striae on propodeum (DV). Lateral of mesosoma and laterally with irregular to vermicular striae directed to propodeal spine, interspaces distinguishable. Wings unknown. MALE Unknown.

Etymology. Sagax (Latin) = wise, sagacious.

Comments. This species is similar to H. virginiae and H. mitiae in the vermicular sculpture on the head dorsum and mesosoma, and the anastomosed striae on the postpetiole and first gastral tergite. Hylomyrma sagax is distinguished from H. virginiae (characteristic in parentheses) based on the following characters: a pair of large teeth laterally at the clypeus anterior margin (vs. a pair of medium teeth), the propodeal spine comparatively longer and needle-like (vs. shorter and thicker), and the continuous dorsal margin of petiole (vs. discontinuous). Hylomyrma sagax is distinguished from H. mitiae in the pair of large teeth laterally at the clypeus anterior margin (vs. medium teeth), the presence of smooth interspaces between the vermicular striae on the entire mesosoma (vs. smooth interspaces only on the mesosomal dorsum; the lateral of mesosoma is covered with very thin striae with indistinguishable interspaces), and the convex subpostpetiolar process (vs. subtriangular). All three species are allopatric; Hylomyrma sagax is restricted to southeast Colombia ( Fig. 83 ), whereas H. mitiae occurs in French Guiana ( Fig. 87 ), and H. virginiae is recorded in Ecuador (both sides of The Andes) and in western Colombia ( Fig. 89 ).

Distribution. This species is only known from southeast Colombia ( Fig. 83 ).

Natural history. Only one worker is known, apart from the type specimens. All material examined was collected from leaf-litter of tropical rainforest, which suggests that nests are located in fallen logs, rotten wood, between leaves, or inside natural cavities of the superficial soil layers.

Additional material examined (1 worker): COLOMBIA: Caquetá: [Puerto] Solano, PNN [Serranía de] Chiribiquete, R. Sararamano, B. Verde military , 300m, 0°10′48″N, 72°37′24″W, Winkler 14, 9.iv.2000, E. González leg. (1W covered with gold) [ IHVL] .

Figures

FIGURE 69. Paratype worker of Hylomyrma sagax (MZSP67450). A) frontal view; B) dorsal view; C) lateral view. Photos by Ricardo Kawada.

FIGURE 70. Paratype queen of Hylomyrma sagax (MCZC35422). A) frontal view; B) dorsal view; C) lateral view. Photos by M.A. Ulysséa.

FIGURE 83. Distribution records of Hylomyrma adelae, H. dandarae, H. longiscapa, H. montana, and H. sagax.

FIGURE 87. Distribution records of Hylomyrma dolichops, and H. mitiae.

FIGURE 89. Distribution records of Hylomyrma lopesi, H. margaridae, H. peetersi, H. transversa, and H. virginiae.