Tetheamyrma bidentata, Genera & Buenavente, 2018

Genera, David Emmanuel M. & Buenavente, Perry Archival C., 2018, Revision and redefinition of the crematogastrine ant genus Tetheamyrma BOLTON, 1991, with the description of a new species and the first description of the dealate queen (Hymenoptera: Formicidae), Myrmecological News 28, pp. 45-51 : 47-50

Tetheamyrma bidentata GENERAL & BUENAvENTE sp.n.

Figures 2a - c , 3a - c

Holotype worker measurements (mm): CI 10 0, EL 0.05, HL 0.41, HW 0.41, ML 0.45, PW 0.26, SI 5 8, SL 0.24.

Paratype worker measurements (n = 17, mm) [mean value and range]: CI 9 6 (8 7 - 111), EL 0.0 5 (0.0 5 - 0.0 6), HL 0.4 6 (0.41 - 0.5 0), HW 0.4 4 (0.4 0 - 0.5 0), ML 0.51 (0.45 - 0.58), PW 0.30 (0.26 - 0.34), SI 57 (50 - 66), SL 0.2 5 (0.21 - 0.29).

Worker: Monomorphic ants. Head densely rugo-reticulate dorsally, laterally, and ventrally, except for smooth genal bridge. Frontal lobes sculptured. Head pilosity composed of stiff decumbent hairs about as long as distance between them. In full-face view, head widest behind eyes, narrowing slightly anteriorly. Posterior margin of head shallowly emarginated. Antennae with 10 segments, with very large 2-segmented club. Antennal scape short, just reaching level of posterior margin of eye, smooth except for piligerous punctures, with short decumbent hairs. Antennomeres 3 to 8 much broader than long. Antennal scrobe absent. Compound eye small, composed of about eight ommatidia, located laterally, entirely forward of midlength of head. Frontal carina short, slightly beyond level of anterior margin of eye. Frontal lobes broad, completely concealing torulus, much wider than posterior clypeus inserted between them. Median clypeus narrowly bicarinate, with carinae starting at posterior clypeus and terminating at the apices of bidentate process. Anterior clypeal margin produced into median bidentate process. Mandible triangular, smooth. Mandibular dentition composed of apical and subapical teeth, a short diastema, third tooth (shorter than subapical tooth), and three to four denticles. Basal external margin of mandible smooth.

In lateral view, palp formula 2,2 (undissected). Occipital carina present. Mesosomal outline smoothly con- vex. Promesonotal suture absent. Metanotal groove very weakly impressed. Mesosoma densely rugo-reticulate dorsally and laterally. Metapleuron and propodeal declivity smooth. Mesosomal pilosity composed of short, erect hairs on dorsum, except for glabrous propodeal declivity. Propodeal declivity steeply sloped. Propodeum with short, acute, triangular spines. Infradental lamella between propodeal spine and metapleural lobe absent. Metapleural lobe low and rounded. Propodeal spiracle circular, somewhat posteriorly directed. Petiole rugo-reticulate dorsally and laterally. Petiole blocky with short peduncle and straight anterior face. Anterodorsal corners of petiole node produced into acute angles. Anteroventral subpetiolar process present. Anteroventral subpetiolar process finely reticulate. Anteroventral subpostpetiolar process present. Anterior face of postpetiole sharply differentiated from dorsal face. Spongiform tissue absent from petiole, postpetiole, and gaster. Spurs absent from mesotibia and metatibia. Sting simple and functional.

In dorsal view, mesosoma rugo-reticulate, widest at the pronotal humeri with lateral margins converging posteriad. Propodeal spines slightly divergent. Petiole node transverse, broader than long. Petiole and postpetiole rugo-reticulate. Dorsum of gaster smooth between piliferous scalloped foveae. Foveae diminishing in siZe posteriorly from anterior third of tergite. Gastral pilosity composed of erect fine hairs slightly longer than distance between them.

In ventral view, genal bridge bounded laterally by a longitudinal carina.

Sculpture: antennal scape smooth to weakly reticulate; head, mesosoma, petiole, and postpetiole dorsally and laterally reticulate, with smooth interstices; mandibles, metapleuron, propodeal declivity smooth; subpetiolar process finely reticulate; gaster smooth be- tween scalloped foveae that bear long, fine setae; foveae diminishing in siZe posteriorly from anterior third of tergite.

Pilosity: head with short, fine, decumbent, recurved setae arising from interstices of reticulate sculpture; a pair of setae straddle anterior median clypeus; a pair of longer setae extend laterally from lateral margin of head behind eyes; antennal scape with short decumbent hairs; a short, decumbent hair may arise from center of compound eye; 4 8 mesosoma, except propodeal declivity, with fine, short erect setae; petiole, postpetiole, and gaster with longer fine, erect setae.

Color: dark reddish brown with brown appendages.

Queen: Measurements (mm): CI 103, EL 0.11, HL 0.50, HW 0.51, ML 0.66, PpH 0.18, PpL 0.13, PpW 0.18, PSL 0.10, PtH 0.18, PtL 0.21, PtW 0.19, PW 0.4 3, SI 5 4, SL 0.2 8.

Larger than worker in all dimensions. In full-face view, head similar to worker except for the presence of ocelli and larger compound eyes. Compound eye with about 50 ommatidia. In lateral view, anterior outline of pronotum precipitous. Dorsal margin of mesosoma moderately flat. Wing scars present. Epimeral sclerite absent. Deep, sinuous suture between posterior margin of pronotum and anterior margin of mesopleuron. Mesopleuron divided by broad, transversely carinate, sulcus. Metanotum dorsally flat, triangular. Propodeal declivity very steep. Propodeal spines triangular. Propodeal spiracle below midlength on sclerite. In dorsal view, mesosoma areolate. Promesonotal suture and metanotal groove impressed. Sculpture, pilosity and color as in worker.

Material examined: HOLOTYPE: worker, PHILIPPI- NES: Samar Island, Western Samar, Municipality of Paranas , Barangay San Isidro , Mukalog Creek , N1 1° 5 2' 0 1.4", E 1 2 5° 1 2' 4 7.2", 174 meters above sea level (m a.s.l.), 12. - 15.III.2016, leg. P.A.C. Buenavente, (collection code PACB128 ), PNM136 37 . PARATYPES: 1 worker, same data as holotype, (collection code PACB15 7), PNM 13 6 2 7; 4 workers, same data as holotype, (collection code PACB131 ), PNM 13628 through PNM 13631; 6 workers, same data as holotype, (collection code PACB152 ), PNM 13632 through 13 6 3 6, and PNM 13 6 3 8; LuZon Island , 1 dealate queen, Bataan , Municipality of Samal , Barangay Palili, Sitio Bakyas, site “B”, N 1 4 ° 4 3' 0 8.3", E 1 2 0 ° 2 3' 4 6.4", 8 3 6 m a.s.l., 02.II.2015, leg. P.A.C. Buenavente and J. Baroga, (collection code PACB19 ), PNM 10769; 1 worker, Laguna , Mt. Banahaw , Municipality of Majayjay , Barangay Bukal, Sitio Pitonggabi, N 1 4 ° 0 5' 5 7.3", E 1 21 ° 2 8' 5 0.2", 7 9 3 m a.s.l., 24.III.2015, leg. P.A.C. Buenavente, (collection code PACB102 ), CASENT0633220, ADMAC DNA voucher, PNM 136 4 3; Mindanao Island , 1 worker, Davao Oriental , Municipality of San Isidro , Mt. Hamiguitan , Barangay La Union, Sitio Tumaguite, N 0 6 ° 4 3' 3 6.6", E 1 26 ° 1 0' 5 8.8", 13 0 0 m a.s.l., 0 4. - 0 6.VII.2016, (D.E.M. General, P.A.C. Buenavente) (collection code PACB16 5), PNM 1 3 6 4 2; 1 worker and 1 dealate queen, Davao Oriental , Municipality of San Isidro , Mt. Hamiguitan , Barangay La Union, Sitio Tumaguite, N 0 6 ° 4 3' 5 9.4", E 1 26 ° 0 9' 5 8.1", 9 8 9 m a.s.l., 0 4. - 0 6.V II. 2 0 16, leg. D.E.M. General and P. A.C. Buenavente, (collection code PACB169 ), PNM 13 6 41 and (collection code PACB170 ), PNM 136 4 4; 2 workers, Davao Oriental , Municipality of San Isidro , Mt. Hamiguitan , Barangay La Union, Sitio Tumaguite, N 0 6 ° 4 4' 0 5.1", E 1 26 °0 8' 3 4.1", 39 6 m a.s.l., 16. - 17.VII.2016, leg. P.A.C. Buenavente, (collection code PACB182 ), PNM 13639 and PNM 136 4 0. All specimens are deposited in NMNH, with accession numbers that start with “ PNM ”.

Bionomics: This species was collected in elevations ranging from about 170 to 1300 m a.s.l. It was collected from leaf litter in good secondary and primary forest.

Etymology: The specific epithet refers to the bidentate anterior clypeal margin of this species.

Figures

Fig.2: Tetheamyrma bidentata sp.n. Paratype worker. (a) Full-face view; (b) lateral view; (c) dorsal view; (d) labels. Images courtesy of M. Pierce and J.T. Longino.

Fig.3: Tetheamyrma bidentata sp.n. Paratype dealate queen. (a) Full-face view; (b) lateral view; (c) dorsal view; (d) labels. Images courtesy of M. Pierce and J.T. Longino.