Hylomyrma montana Pierce, Branstetter & Longino, 2017

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 : 83-86

Hylomyrma montana Pierce, Branstetter & Longino, 2017

Figures 55 , 56 , 83 (map)

Hylomyrma montana Pierce, Branstetter & Longino, 2017: 138 (W). Holotype: COSTA RICA: Limón: Cerro Platano , 9.86732 –83.24131 ± 20 m, 1130 m [a.s.l.], 18 June 2015, [Project] ADMAC [collection code] #Wm-E-03-1-01, cloud forest, ex sifted leaf litter (1W) (CASENT0637306) [CASC] [examined by image]. Paratypes: same data as holotype (1W) (CASENT0638686) [MCZC] [not examined]; (1W) (CASENT0638689) [UCD] [not examined]; (1W) (CASENT0638690) [UCR] [not examined]; (1W) (CASENT0638691) [USNM] [not examined]; (7W) (CASENT0638721, CASENT0638702, CASENT0638694, CASENT0638692, CASENT0638699, CASENT0638696, CASENT0638695) [JTLC] [not examined]; (1W) (CASENT0638719 MZSP67405 ) [MZSP] [examined].

Worker ( Fig. 55A–C ) Diagnosis. Regular and longitudinal striae on head dorsum diverge towards posterior margin, interspaces between thicker striae filled with thinner striae; regular and irregular striae on mesosoma assuming multiple directions, interspaces smooth; dorsal tooth of propodeal lobe acute, ventral tooth blunt; dorsal margin of mesosoma slightly discontinuous, somewhat straight (mesosoma slightly flattened dorsally), promesonotal junction and metanotal groove discernible by a slight depression (LV) and altered sculpture (DV); propodeal spine long; dorsal margin of petiole continuous, convex; ventral surface with transverse striae from petiole spiracle to posterior end of petiole; irregular, longitudinal and anastomosed striae node dorsum; postpetiole smooth; subpostpetiolar process predominantly smooth, weak, convex; profemur posterior surface and protibia extensor surface smooth; striation on tergum of first gastral segment restricted to base, very short striae.

QUEEN (first description) (n=3) ( Fig. 56A–C ): HL (1–1.02); HW (0.96–0.97); ML (0.64–0.68); SL (0.72–0.74); MOD (0.24–0.26); PNW (0.78–0.80); WL (1.48–1.51); PSL (0.31–0.34); PL (0.71–0.74); PW (0.28–0.30); PPL (0.36–0.38); PPW (0.42); GL (1.30–1.36); TL (5.49–5.62); CI (95.10–97); SI (74.22–77.08); OI (24.74–26.80). Large-sized. Color, pilosity, and some sculpture characters shared with conspecific workers, only slightly larger. Larger diameter of eye with 12–13 ommatidia. Longitudinal, regular to irregular striae on scutum going from an anterior central point towards transcutal suture, interspaces distinguishable. Longitudinal and mostly irregular striae on anepisternum and katepisternum, interspaces distinguishable. Axilla and scutellum with same sculpture of scutum. Scutoscutellar sulcus inconspicuous. Transverse striae on propodeum (DV). Irregular striae on mesosoma lateral directed in part to propodeal dorsum and in part to propodeal spine, interspaces distinguishable. Wings unknown.

MALE Unknown.

Etymology. The specific epithet is in reference to the montane distribution of this species.

Comments. This species is easily distinguished from almost all of its congeners, but it is very similar to H. lispectorae regarding the shape of mesosoma, and the sculpture and shape of the procoxa, petiole, postpetiole, and gaster. The two species are sympatric, co-occuring in two Ecuadorian localities: Centro Científico Río Palenque, and 4 km E of Santo Domingo de los Colorados ( Figs. 83 , 84 ). Hylomyrma montana can be distinguished from H. lispectorae (characteristic in parentheses) by the dorsum of head and mesosoma with irregular striae of uniform thickness with interspaces distinguishable (vs. vermicular striae of variable thickness with interspaces indistinguishable), and the somewhat straight dorsal margin of mesosoma (vs. notably convex).

The morphological variation displayed by H. montana is associated with the presence of intercastes. Three specimens have an inconspicuous central ocellus, and a more pronounced depression on the metanotal groove. Two specimens (#17842, #17840) from Chiriqui-Bocas del Toro, Panama, have more queen-like traits, as larger bodies [HL (1); HW (0.94–0.98); ML (0.58–0.62); SL (0.68–0.70); MOD (0.22–0.23); PNW (0.25–0.26); WL (1.32–1.34); PSL (0.30–0.31); PL (0.64–0.65); PW (0.25–0.26); PPL (0.36); PPW (0.35–0.38); GL (1.18–1.30); TL (5.09–5.26)], the presence of three ocelli, the well-marked promesonotal suture, the differentiated mesonotum (scutum, transcutal suture, prescutellum, and scutellum) and metanotum.

Distribution. Costa Rica, Ecuador, and Panama ( Fig. 83 ).

Natural history. This species inhabits wet forest sites at elevations between 29 and 1800 m. Specimens are frequently found in leaf-litter samples, which suggests that nests are located in leaf-litter, fallen logs, rotten wood, or inside natural cavities of the superficial soil layers. Except for the presence of intercastes, there is no further information available regarding the biology of H. montana .

Additional material examined (40 workers, 15 queens, 5 intercastes): COSTA RICA: Heredia: 16km SSE La Virgem , 10.26877 -84.08531 + 200m, 1110m, 1.iv.2001, ALAS #11/WF/01/all montane wet forest, ex sifted leaf litter (2I) [ MZSP]. ECUADOR: Cotopaxi: Otonga , 00°25′S, 79°00′W, 2AUG1977, L. Tapia & P. Ponce, ex monte, B5, QCAZ I 26128 (1Q) [ UTLP] ; same except MN008I, LL4-P2WI (1Q) [ UTLP] ; [Los Rios]: Rio Palenque, Univ. Miami Res. Sta. , 29July.1978, G.J. Umphrey (1W) (MCZENT00525538) [ MCZC] ; Agosto/Septiembre, 1977, 55235, Bosque primario, cuad.cerr, QCAZ I 114015 (1Q) [ UTLP] ; Pichincha: Centr. Cient. R. Palenque , 4.i.1981, Sonia Sandoval col., Bosque primario cerrado, 196 (1Q) [ IHVL] ; same except 28.ii.1981, 279 (1Q) [ IHVL] ; 4km E Santo Domingo de los Colorados , 8.vii.1976, S. & J. Peck (2Q) (MCZENT00524645, MCZENT00524644) [ MCZC] ; 4km E Santo Domingo de los Colorados , 520m, 22 June 1975, rainfor., B-304, S. & J. Peck (2W) (MCZENT00524657, MCZENT00524665) [ MCZC] ; same data (1W) (MZCENT00524664) [ MZSP] ; 20-30km ENE Alluriquin on Chiriboga Rd., 1400-1800m, moss for., B301, 1975, S. & J. Peck (1W 1Q) (MCZENT00524672, MCZENT00524671) [ MCZC] ; Otongachi , 850m, 0°18′49″S, 78°57′15″W, 04SEP2009, G. Ramón, KT-601, LL8W14 (2W) [ UTLP] ; same except KT-1668, LL8W7 (2W) [ UTLP] ; KT-691, LL8W1 (1W) (MZHY213) [ MZSP] ; KT-691, LL8W1 (1W) [ IHVL] ; 04-AUG-2008, D. Donoso, KT-1270, LL6-W2 (2W 1Q) [ MZSP] ; 03AUG2011, G. Ramón, VD-604, LL12-PF18 (1Q) [ MZSP] ; 06AUG2009, G. Ramón, KT-1055, GR-018 (1Q) [ UTLP] ; Tinalandia, 16km SE S. Domingo de los Colorados, 5.vi.1976, S. & J. Peck (5W) (MCZENT00524687, MZCENT00525525, MZCENT00524685, MZCENT00525526, MZCENT00524686) [ MCZC] ; same data (1W) (MZCENT00525527) [ MZSP] ; same except 4.vi.1976 (1W) (MCZENT00525483) [ MCZC] ; 680m, B-300, (1W 1Q) ( MIZA0021697 , MIZA0021698 ) [ MIZA] ; 680m (1Q) ( MIZA0021700 ) [ MIZA] ; Río Toachi , 900m, 0.3304033°S, 78.9413833W, 05.Sep.2003, D. Donoso, KT-786, N.O W LL-1, 19/26 (2W, one covered with gold) ( MZSP67433 ) [ MZSP] ; same except LL1P11W48h, xc275, QCAZ I 59348 (1W 1Q) [ MZSP]. PANAMA: Chiriqui-Bocas del Toro : Cont. Div., 9.vi.95, R. Anderson, #17845 (2W) MZSP] ; same data (1W) [ UTEP] ; (2W) [ DZUP] ; same except #17842 (8W 1I) [ MZSP] ; #17840 (2I) [ MZSP] ; La Fortuna area, 9.v.95, R. Anderson, #17846 (1W 1Q) ( MZSP67406 ) [ MZSP] ; Veraguas: 6.1k N Santa Fe, Cerro Tute , 1220m, 13.vi.1996, litter extr., wet cloud for., R. Anderson, #17893 (1W) [ MZSP] ; same except #17891 (1W) [ UTEP] .

Figures

FIGURE 55. Holotype worker of Hylomyrma montana (CASENT0637306). A) frontal view; B) dorsal view; C) lateral view. Photos by Michele Esposito, available from www.antweb.org.

FIGURE 56. Queen of Hylomyrma montana (MZSP67406). 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 84. Distribution records of Hylomyrma balzani, H. blandiens, H. jeronimae, and H. lispectorae.