Hylomyrma virginiae Ulysséa, 2021

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 : 123-126

Hylomyrma virginiae Ulysséa new species

Figures 77 , 78 , 80D , 89 (map)

Holotype: ECUADOR: Napo: Limoncocha , 250m, 25.vi.1976, B-355, S. & J. Peck [leg.] (1W) (MCZENT00524688) [ MCZC] . Paratypes: same data as holotype (5W) (MCZENT00525482, MCZENT00524690, MCZENT00525503, MCZENT00525523, MCZENT00524689) [ MCZC] ; (1W) (MCZENT00525522 MZSP67462 ) [ MZSP] ; (1W) (MCZENT00525518 MZHY196) [ MZSP] ; (1W) (MCZENT 00525524) [ USNM] ; (1W) (MCZENT00525517) [ DZUP] ; (1W) (MCZENT00525521) [ IHVL] ; (1W) (MCZENT00525519) [ CASC] ; same except 18.vi.1976, B-348 (4W) (MCZENT00525501, MCZENT00524677, MCZENT00524676, MCZENT00525499) [ MCZC] ; (1W) (MCZENT00525506 MZSP67463 ) [ MZSP] ; (1Q) (MCZENT00524678 MZSP67464 ) [ MZSP] ; 20km S of Tena , 600m, 11Jul 1976, B360, S. & J. Peck [leg.] (1W) (MCZENT00525490) [ MCZC] ; Pichincha: Centr. Cient. R. Palenque , 20.xii.1980, Sonia Sandoval col., Bosque primario cerrado, 584 (1W covered with gold) [ IHVL] ; Los Rios: C.C.R. Palenque , 79°45′10″W, 01°25′56″S, 02MAR1979, S. Sandoval (1Q) ( QCAZ I 114012 ) [ QCAZ] ; Pastaza: 22km SW Puyo, 15 July 1976, B-362, S. & J. Peck [leg.] (1Q) (MCZENT00524681) [ MCZC] .

Diagnosis. Vermicular to vermiculated-areolated striae on head dorsum and mesosoma; petiole anterior surface well-marked; transverse striae on node ventral surface; longitudinal and anastomosed striae on postpetiole and tergum of first gastral segment; subpostpetiolar process weak, slightly convex; profemur posterior surface mostly smooth; protibia extensor surface entirely striate; long striae on tergum of first gastral segment; setae with 2 short branches of equal size arising from the main axis.

Description. WORKER (n=3) ( Fig. 77A–C ): HL (0.94–1.04); HW (0.90–1.04); ML (0.66–0.70); SL (0.68–0.80); MOD (0.26–0.27); PNW (0.64–0.74); WL (1.24–1.40); PSL (0.28–0.38); PL (0.59–0.64); PW (0.24–0.27); PPL (0.36–0.40); PPW (0.36–0.38); GL (1.02–1.12); TL (4.94–5.20); CI (95.74–100.97); SI (73.07–77.67); OI (25– 28.90). Medium to large-sized. Shiny integument. Head, postpetiole and gaster dark brown, lighter mesosoma, leg and petiole. Thin and branched setae, long to midsized, erect to subdecumbent; 2 short branches of equal size arising from the main axis ( Fig. 80D ).

Head subquadrate; posterior margin concave at middle. Mandible masticatory margin with 6 teeth. Anterior margin of clypeus concave medially, with a pair of medium teeth laterally; median area of clypeus with 5 irregular and longitudinal striae converging to a point on the anterior margin, interspaces distinguishable. Frontal triangle with 1–2 striae. Short scape, not reaching head posterior margin; apical antennomere slightly shorter than previous 3 antennomeres together. Frontal carina slightly concave posterior to antennal socket. Eye drop-shaped, small-sized, larger diameter with 10 ommatidia. Head dorsum with vermicular to vermiculated-areolated striae, divergent towards posterior margin, interspaces smooth. Striae on head lateral and laterodorsal regions converge to eye margin; very thin striae with interspaces indistinguishable (microsculpture) superimposed on vermicular to vermiculatedareolated striae (macrosculpture); gena striate, with the same striation of head lateral, 2–3 regular and semicircular striae circumscribe the torulus, not reaching eye margin. Interspaces between striae on head ventral surface distinguishable.

Vermicular to vermiculated-areolated striae on mesosoma, interspaces between thicker striae smooth on mesosoma dorsum and filled with thinner striae on mesosoma lateral. Promesonotal junction and metanotal groove indistinct. Transverse carina well-marked. Dorsal margin of mesosoma continuous, slightly convex. Propodeal lobe bidentate, dorsal tooth longer and more acute than the shorter and blunt ventral tooth; dorsal tooth length 1 / 2 of propodeal spine length. Propodeal spine midsized, straight (LV), divergent (DV), sculptured on base. Procoxa with thin and transverse striae of uniform thickness; irregular and transverse striae on C2 and C3. Irregular to regular transverse striae on profemur dorsal surface; posterior surface mostly smooth; anterior and ventral surface completely smooth. Protibia extensor surface entirely striate.

Dorsal margin of petiole discontinuous, smooth dorsum. Node with irregular and transverse striae on anterior surface continuing on lateral surface; vermiculated-areolated striae on lateral and dorsal surfaces; irregular and transverse striae on ventral surface, interspaces distinguishable. Longitudinal and anastomosed striae on postpetiole; subpostpetiolar process striae restricted to lateral region; subpostpetiolar process weak, slightly convex.

First gastral segment striation similar to postpetiole striae; long striae on tergum, 1 / 4 longer than postpetiole length; sternite striation weakly marked, covering the laterobasal region.

QUEEN (n=3) ( Fig. 78A–C ): HL (0.98–1.12); HW (1.01–1.10); ML (0.66–0.74); SL (0.76–0.90); MOD (0.28– 0.33); PNW (0.80–0.96); WL (1.48–1.72); PSL (0.35–0.43); PL (0.66–0.74); PW (0.26–0.30); PPL (0.40–0.44); PPW (0.40–0.49); GL (1.40–1.64); TL (5.58–6.40); CI (98.09–103.06); SI (75.24–81.81); OI (27.20–30). Largesized. Color, pilosity, and some sculpture characters shared with conspecific workers, only slightly larger. Larger diameter of eye with 13–14 ommatidia. Longitudinal, irregular to vermicular striae on scutum going from an anterior central point towards transcutal suture, interspaces distinguishable. Anepisternum, katepisternum, axilla and scutellum with the same sculpture of scutum. Scutoscutellar sulcus inconspicuous. Transverse and regular striae on propodeum (DV). Lateral of mesosoma with irregular to vermiculated-areolated, thicker striae directed mostly to propodeal dorsum, interspaces between striae smooth. Wings unknown.

MALE Unknown.

Etymology. The epithet virginiae is a Latin noun in the genitive case created by adding the singular Latin genitive case suffix -e to the first name of a female person. This species is named in honor of Virginia Leone Bicudo (1910–2003), a sociologist and psychoanalyst born in São Paulo, daughter of an Italian immigrant and a black Brazilian. She was the first non-medical practitioner to be recognized as a psychoanalyst, therefore essential for the development and institutionalization of psychoanalysis in Brazil. She was a pioneer in the study of relations between races, which was the subject of her dissertation in 1945.

Comments. Hylomyrma virginiae is not known to co-occur with H. mitiae or H. sagax , but all three occur in northwestern South America. Hylomyrma virginiae has been recorded in Ecuador (both sides of The Andes) and in western Colombia ( Fig. 89 ), whereas H. sagax is restricted to southeast Colombia ( Fig. 83 ), and H. mitiae only occurs in French Guiana ( Fig. 87 ). Hylomyrma virginiae is typically smaller (TL 4.94–5.20 mm, WL 1.24–1.40 mm) than H. mitiae (TL 5.27–5.52 mm, WL 1.41–1.52 mm). Also, the gena and laterodorsal region of the head are covered by very thin striae with indistinguishable interspaces superimposed on vermicular to vermiculated-areolated striae (vs. very thin striae with indistinguishable interspaces between the vermicular to vermiculated-areolated striae in H. mitiae ) (not seen in SEM images of H. mitiae due to coating artifacts), the indistinct metanotal groove (vs. distinguished by slight depression), the discontinuous dorsal margin of petiole (vs. continuous), and the weak and slightly convex subpostpetiolar process (vs. very prominent and subtriangular). Hylomyrma virginiae can be distinguished from H. sagax (characteristic in parentheses) in the medium lateral teeth at clypeus anterior margin (vs. well-developed teeth), the propodeal spine comparatively shorter and thicker (vs. longer and needle-like), and the discontinuous dorsal margin of petiole (vs. continuous).

There are relatively few specimens collected of this species; most were sampled in Limoncocha, Ecuador. Specimens from Chocó, Colombia, have a more developed propodeal spine and subpostpetiolar process, and the anterior surface of petiolar node is slightly marked. These characteristics may lead to the misidentification of these specimens as H. sagax , but their body size and sculpture are more similar to those found in H. virginiae specimens recorded in Ecuador.

Distribution. Hylomyrma virginiae is known from Colombia and Ecuador ( Fig. 89 ).

Natural history. This species occurs in tropical rainforests and areas of bamboo ( Guadua sp. ) plantations, at elevations between 250 and 850 m. Specimens were collected in the leaf-litter, 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 (8 workers): COLOMBIA: Chocó: 10km SW S.[San] José del Palmar, Rio Torito , 1–4.june.1978, C. Kugler col., Finca Los Guaduales, 800m, in Guadua sp. litter (6W) [ MCZC]; same except 610m, by river (1W) [ MCZC]; 850m, on ridge, litter (1W) [ MCZC] .

Figures

FIGURE 77. Holotype worker of Hylomyrma virginiae (MCZENT00524688). A) frontal view; B) dorsal view; C) lateral view. Photos by Ricardo Kawada.

FIGURE 78. Paratype queen of Hylomyrma virginiae (MCZCENT00524681). A) frontal view; B) dorsal view; C) lateral view. Photos by M.A. Ulysséa.

FIGURE 80. Types of setae found in the species of Hylomyrma. Unbranched setae: A) Hylomyrma adelae, H. blandiens, H. macielae; B) H. immanis; C) H. marielleae. Branched setae: D) H. dentiloba, H. lispectorae, H. mitiae, H. peetersi, H. virginiae; E) H. balzani, H. lopesi; F) H. blandiens, H. jeronimae, H. versuta; G) H. dolichops; H) H. transversa; I) H. longiscapa; J) H. balzani, H. lopesi, H. primavesi, H. reitteri, H. versuta; K) H. plumosa.

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.