Hylomyrma margaridae 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 : 72-75

Hylomyrma margaridae Ulysséa new species

Figures 48 , 49 , 89 (map)

Holotype: GUYANA: Upper Takutu-Upper Essequibo: Acarai Mts., nr. New Romeo Camp , 1038m, 58°57.876′W, 1°20.066′N, 14.x.2006, T.R. Schultz, J. Sosa-Calvo, C.J. Marshall, R. Williams, 1° forest, leaf litter, Winkler sample, JSC061014- LS04 (1W) (USNMENT00688842) [ USNM] . Paratypes: same data as holotype (1W) (USNMENT00688836 MZHY195) [ MZSP] ; (2W 1Q, one worker covered with gold) (USNMENT00688820, USNMENT00688844, USNMENT00688842) [ USNM] ; same except 1050m, 58°57.876′W, 1°20.048′N, JSC061014-LS03 (1W) (USNMENT00688740) [ MCZC]. FRENCH GUIANA: [Cayenne: Saint-Élie], Nouragues Station , FT2-Transition For., 4°09′N, 52°68′O, ix.2009, Sarah Groc & al, #5635, FT2 Tr5 W29 (1Q) ( MZSP67391 ) [ MZSP] ; [Saint-Laurent-du-Maroni: Maripasoula], Mitaraka Mts, Plateau , 2.233158N - 54.44381W, 27.ii.2015, J. Orivel & F. Petitclerc cols., winkler 48h, C-P7-3, MI15-0079-15 (1W) ( MZSP67392 ) [ MZSP].

Diagnosis. Regular and longitudinal striae on head dorsum diverge towards posterior margin, interspaces between striae smooth, striae crest punctuated; mesosoma covered with regular, longitudinal, parallel and thick striae; longitudinal striae on lateral of pronotum, mesepisternum and propodeum directed to propodeal spine; dorsal margin of petiole continuous, strongly convex; spiniform projection on mesoventral surface of petiole; node rounded with transverse striae anteriorly and longitudinal striae posteriorly on dorsum; subpostpetiolar process smooth, prominent, subtriangular; profemur posterior surface and protibia extensor surface mostly smooth, with few striae on basal and apical regions; striation on tergum of first gastral segment restricted to base.

Description. WORKER (n=3) ( Fig. 48A–C ): HL (0.85–0.88); HW (0.79–0.82); ML (0.53–0.55); SL (0.58–0.59); MOD (0.20–0.21); PNW (0.58); WL (1.12–1.18); PSL (0.14–0.16); PL (0.53–0.57); PW (0.21–0.22); PPL (0.32– 0.34); PPW (0.29–0.30); GL (0.86–0.98); TL (4.21–4.50); CI (92.94–94.25); SI (71.95–73.41); OI (25.31–25.61). Small-sized. Shiny integument. Brownish body, darker gaster, yellowish appendices. Few thin and unbranched setae, long to midsized, suberect to subdecumbent.

Head subquadrate; posterior margin straight. Mandible masticatory margin with 5 teeth. Anterior margin of clypeus straight medially, with a pair of small teeth laterally; median area of clypeus with 8–9 striae, regular to irregular, longitudinal, converging to a point on the anterior margin, interspaces distinguishable. Frontal triangle with 1 stria subdivided towards the posterior margin. Short scape, not reaching head posterior margin; apical antennomere of similar size or slightly shorter than previous 3 antennomeres together. Frontal carina straight. Eye dropshaped, small-sized, larger diameter with 9 ommatidia. Regular and longitudinal striae on head dorsum, divergent towards posterior margin, interspaces smooth, striae with punctuated crests. Head laterodorsal sculpture converges to mandible insertion region; head lateral sculpture converges to eye margin; gena striate, 2–3 regular and semicircular striae circumscribe the torulus, not reaching eye margin. Interspaces between striae on head ventral surface distinguishable.

Mesosoma covered with regular and longitudinal striae, thicker than head striation, transverse on pronotum anterior region (DV), longitudinal in the other regions (DV); longitudinal striae on lateral of pronotum, mesepisternum and propodeum directed to propodeal spine. Promesonotal junction and metanotal groove indistinct. Transverse carina well-marked. Dorsal margin of mesosoma continuous, convex. Propodeal lobe bidentate, dorsal tooth longer and with rounded tip; ventral tooth shorter and blunt; dorsal tooth length similar to propodeal spine length. Propodeal spine short, straight (LV), divergent (DV), sculptured on base. Procoxa striae of uniform thickness; irregular and transverse striae on C2 and C3. Profemur and protibia mostly smooth, few striae on basal and apical regions.

Dorsal margin of petiole continuous, strongly convex; smooth spiniform projection on mesoventral surface; ventral surface smooth; first third of dorsal surface and parts of lateral surface smooth, other regions mostly striate, transverse and longitudinal striae. Longitudinal striae on postpetiole; subpostpetiolar process well-developed, subtriangular, smooth.

Tergum first gastral segment striation similar to that of postpetiole; striae short, restricted to base, length shorter than 1 / 4 of postpetiole length; sternum smooth.

QUEEN (n=2) ( Fig. 49A–C ): HL (0.82–0.90); HW (0.80–0.86); ML (0.52–0.58); SL (0.54–0.60); MOD (0.24– 0.26); PNW (0.65–0.70); WL (1.20–1.36); PSL (0.20–0.22); PL (0.58–0.63); PW (0.24–0.26); PPL (0.36–0.38); PPW (0.33–0.34); GL (1.04–1.16); TL (4.52–5.01); CI (95.55–97.56); SI (67.50–69.76); OI (30–30.23). Small to midsized. Color, pilosity, and some sculpture characters shared with conspecific workers, only slightly larger. Larger diameter of eye with 12 ommatidia. Anepisternum, katepisternum, axilla and scutellum with the same sculpture of scutum. Scutoscutellar sulcus inconspicuous. Transverse striae on propodeum (DV). Lateral of mesosoma with longitudinal and regular striae directed to propodeal spine, interspaces distinguishable. Wings unknown.

MALE Unknown.

Etymology. The epithet margaridae 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 Margarida Maria Alves (1933–1983), a Brazilian trade unionist and precursor in defending the rights of rural workers in Paraíba, northeast region of Brazil —“ Da luta eu não fujo. É melhor morrer na luta do que morrer de fome ”. Margarida was murdered for her activism on the 12 of August. Since the year 2000, thousands of women from all of the regions of the country gather every two years in a march for the equal rights for rural women that bears her name—“ Marcha das Margaridas ”.

Comments. This species can be misidentified mainly as H. peetersi and H. villemantae . The three species are allopatric; H. villemantae occurs in one locality in northeastern Brazil (BA) ( Fig. 86 ), H. margaridae occurs in Guyana and French Guiana ( Fig. 89 ), and H. peetersi in areas near the Guyana - Venezuela border ( Fig. 89 ).

Hylomyrma margaridae can be distinguished from H. peetersi (characteristic in parentheses) in the striae on the laterals of mesosoma that are directed transversely towards the propodeal spine (vs. directed to the propodeal dorsum), the mesoventral surface of petiole armed with a conspicuous spine (vs. a subtriangular projection), the petiolar dorsum covered with both transverse and logitudinal striae (vs. entirely covered with transverse striae), and the prominent subpostpetiolar process (vs. weak). Hylomyrma margaridae can be distinguished from H. villemantae in the striae on the head dorsum with punctuated crests (vs. with smooth crests), the mesosoma longitudinally striate (vs. with few elliptical and concentric striae), the shorter propodeal spine (vs. longer), the armed mesoventral surface of petiole (vs. unarmed), and the smooth dorsum of postpetiole and gaster (vs. striate).

Hylomyrma margaridae and H. lopesi have similar shape and sculpture of the mesosoma. Nevertheless, H. margaridae has a reniform eye (vs. oval eye of H. lopesi ), the striae on the head dorsum with punctuated crests (vs. with smooth crests), and the continuous dorsal margin of petiole (vs. discontinuous). The two species are allopatric ( Fig. 89 ); H. margaridae occurs in Guyana and French Guiana, and H. lopesi in Brazil.

Regarding morphological variation, the queen collected in French Guiana has the petiolar node covered with concentric striae that circumscribe its anterodorsal, lateral and posterior regions.

Distribution. This species is known from the southern part of the Upper Takutu-Upper Essequibo region in Guyana, and from the Réserve Naturelle Nationale des Nouragues, in the central region of French Guiana ( Fig. 89 ).

Natural history. This species has been recorded with winkler extractors in forested areas at high elevations ranging from 1038 to 1050 m in Guyana and at lower elevations in French Guiana (Nouragues Station is located at about 124 m and Mitaraka Mountain at 554 m).

Figures

FIGURE 48. Holotype worker of Hylomyrma margaridae (USNMENT00688842). A) frontal view; B) dorsal view; C) lateral view. Photos by Ricardo Kawada.

FIGURE 49. Paratype queen of Hylomyrma margaridae (USNMENT00688833). A) frontal view; B) dorsal view; C) lateral view. Photos by M.A. Ulysséa.

FIGURE 86. Distribution records of Hylomyrma dentiloba, H. macielae, H. reginae, H. villemantae, and H. wachiperi.

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