Pseudomyrmex fasciatus, Ward & Branstetter, 2022

Ward, Philip S. & Branstetter, Michael G., 2022, Species Paraphyly and Social Parasitism: Phylogenomics, Morphology, and Geography Clarify the Evolution of the Pseudomyrmex elongatulus Group (Hymenoptera:, Insect Systematics and Diversity (AIFB) 6 (1), pp. 1-31 : 24-25

Pseudomyrmex fasciatus sp. nov.

Figs. 15 and 20

Zoobank LSID: urn:lsid:zoobank.org:act:52CB59B3-D99C-4E09-8A83-522B3E21714F

Holotype Worker. COSTA RICA Puntarenas: 2 km SSE Monteverde , 1,230 m, 10.289 06 −84.80304 ± 3 m, 5 Jan 2018, ex dead twig of vine, montane rainforest edge, P. S. Ward PSW18011 ( MUCR) ( CASENT0863540 ) . Paratypes: series of workers, 1 dealate queen, same data as holotype (CASC, JTLC, LACM, MCZC, PSWC, UCDC, UNAM, USNM).

Other material examined (AMNH, INBC, JTLC, LACM, MCZC, MIZA, MUCR, PSWC, SMPC, UCDC, USNM).

Costa Rica: Alajuela: Rio Peñas Blancas, 950 m (Longino, J.); Zarcero, 1,600 m (Solis, A.); Cartago: Agua Caliente, nr. Cartago (Wheeler, W. M.); Nombre Dulce, vivero Linda Vista, 1,300 m (Hanson, P.); Heredia: Monte Allegro, Sto. Domingo de Heredia (Perfecto, I.); Puntarenas: 2 km SSE Monteverde, 1,230 m (Ward, P. S.); 2 km SSW Monteverde, 1,245 m (Ward, P. S.); 3 km SE Monteverde, 1,200 m (Longino, J.); 3 km SSE Monteverde, 1,100 m (Longino, J.); Monteverde, 1,100 m (Ward, P. S.); Monteverde, 1,200 m (Cover, S.); Monteverde, 1,200 m (Ward, P. S.); Monteverde, 1,400 m (Longino, J.); Monteverde (Daly, H.); San Luis de Monteverde, 1,100 m (LaPierre, L.); San Luis Valley, 1,090 m (Sumnicht, T. P.; Longino, J. T.); Sta. Elena, 1,300 m (Longino, J.); vic. Alto San Luis, 1,100 m (Hovore, F. T.); San José: San Pedro de Montes de Oca (Ballou, C. H.); El Salvador: La Libertad: Ecoparque El Espino (Mendoza, E.); Guatemala: Chimaltenango: El Amparo (c.u.);

Escuintla: 6.6 mi NE Escuintla (Janzen, D. H.) ; Guatemala: ex Guatemala City (in quarantine San Francisco, USA) (c.u.) ; Santa Rosa : El Piño (Sivinski, J.) ; unknown: ex ‘ Guatemala’ (intercepted at Hoboken , NJ, USA) (c.u.) ; Honduras: Atlántida: 9 km S Yaruca , 950 m (Ward, P. S.) ; Cortés: Lago Yojoa, N end (Brown, W. L.) ; PN Cusuco , 1,210 m ( LLAMA) ; PN Cusuco , 1,330 m ( LLAMA) ; Mexico: Chiapas: 15 mi NW Ocozocoautla , 790 m (Newton, A.) ; Finca Hamburgo, Río Tepuzapa , 1,030 m (Andresen, D.) ; Finca Irlanda , 975 m (Philpott, S. M.) ; Nahá , 860 m ( LLAMA) ; Nahá , 950 m ( LLAMA) ; Sierra Morena , 1,380 m ( LLAMA) ; Nicaragua: Matagalpa: RN Cerro Musún, 1,090 m ( LLAMA) ; RN Cerro Musún , 750 m ( LLAMA) ; RN Cerro Musún , 880 m ( LLAMA) ; RN Cerro Musún , 900 m ( LLAMA) .

Worker measurements (n = 12). HW 0.84–0.94, HL 1.05–1.15, MFC 0.019 –0.042, LHT 0.74–0.83, CI 0.79–0.86, FCI 0.023 –0.045, REL 0.45–0.48, REL2 0.54–0.59, FI 0.41–0.47, PLI 0.46–0.58, PWI 0.42–0.50, MSC 2–5.

Worker Diagnosis. Small to medium-sized species ( HW 0.84– 0.94) with moderately elongate head ( CI 0.79–0.86) ( Fig. 15 ) and relatively large eyes ( REL 0.45–0.48); frontal carinae separated by less than basal scape width; metanotal groove weakly impressed, in profile barely discernable; dorsal face of propodeum flat, rounding into declivitous face, and the two subequal in length; petiole relatively slender ( PLI 0.46–0.58, PL/HL 0.54–0.60); in profile, anterodorsal face of petiole flat to convex, ascending gradually to summit in posterior half of node, then rounding into more steeply descending posterior face; profemur generally slender ( FI 0.41–0.47); hind leg relatively short ( LHT /HL 0.67- 0.76). Head subopaque to sublucid, densely punctulate-coriarious, the punctulae on vertex separated by less than their diameters. Standing pilosity sparse, absent from propodeum and mesonotum ( MSC 2–5). Light yellow- to orange-brown, with dark brown anterolateral patches on abdominal tergite 4 (first gastric tergite), sometimes joined medially, and conspicuous transverse bands on abdominal tergites 5 and 6 (gastric tergites 2 and 3); distal half of metafemur weakly (and variably) infuscated.

Comments. Among species in the P. elongatulus group that are predominantly yellow-orange to light orange-brown in color, this species can be recognized by the combination of relatively large eyes (worker REL 0.45–0.48, queen REL 0.45–0.46), moderately elongate head (worker CI 0.79–0.86, queen CI 0.72–0.76), weakly developed metanotal groove in the worker, and conspicuous transverse maculation on abdominal tergites 4–6 (gastric tergites 1–3). Our phylogenomic data reveal that P. fasciatus is sister to P. cognatus (including its phylogenetically embedded inquiline, P. comitator ) (Fig. 1). Pseudomyrmex fasciatus and P. cognatus are broadly sympatric and quite different in appearance, with workers and queens of P. cognatus being brown to brownish-black in color.

Distribution and Biology. Pseudomyrmex fasciatus occurs from Chiapas, Mexico to Costa Rica. Recorded habitats include montane rainforest edge, montane wet forest, montane moist forest, and second-growth forest edge, at elevations ranging from 750 m to 1,600 m (mean 1,115 m; n = 28). Nests have been collected in dead twigs of various woody plants, including vines and orchids. Two series of specimens intercepted in quarantine at San Francisco, from Guatemala, are labeled ‘ex Oncidium wentworthianum ’ and ‘ex Epidendrum atropurpurium ’, respectively. A third interception, at Hoboken, New Jersey was from an Oncidium stem.

Figures

Fig. 13–15. Pseudomyrmex elongatulus group, workers, full-face dorsal view of head (a), and lateral profile of body (b). 13, P. capillatus, holotype, Mexico (CASENT0863535); 14, P. exoratus, holotype worker, Mexico (CASENT0863539); 15, P. fasciatus, holotype, Costa Rica (CASENT0863540). Images from AntWeb (www.antweb.org); photographer PhilWard.

Fig. 19–26. Pseudomyrmex elongatulus group: distribution maps. 19, P. apache; 20, P. arcanus (circles), P. fasciatus (triangles); 21, P. championi; 22, P. capillatus (triangles), P. cognatus (circles); 23, P. elongatulus (circles), probable introduced populations (stars); 24, P. comitator (square), P. ereptor (triangle), P. exoratus (circles); 25, P.salvini; 26, P. nimbus (circles), P. veracruzensis (triangle).