Adelomyrmex marginodus Longino

Longino, John T., 2012, A review of the ant genus Adelomyrmex Emery 1897 (Hymenoptera, Formicidae) in Central America, Zootaxa 3456, pp. 1-35 : 20-22

Adelomyrmex marginodus Longino , sp. nov.

( Figs 3 , 16 , 21 )

Type material. Holotype worker Honduras, Atlántida: 7 km SSW Tela, 15.72337 −87.45177 ± 20 m, 190 m, 15 Jun 2010 ( LLAMA Wa-C- 08-2-43) [ CAS, unique specimen identifier CASENT 0627826]. Paratypes (workers): Honduras, Atlántida: 7 km SSW Tela, 15.72453 −87.45192 ± 20 m, 190 m, 15 Jun 2010 ( LLAMA Wa-C- 08-2-17) [ MCZC, CASENT 0618409]; Honduras, Atlántida: 12km SW La Ceiba, 15.69130 −86.86076 ± 20 m, 280 m, 19 Jun 2010 ( LLAMA Wa-C- 09-2-17) [ BMNH, CASENT 0627830], [ EAPZ, CASENT 0627831], [ECOSCE, CASENT 0627832], [ MZSP, CASENT 0627828], [ UCD, CASENT 0627833], [ USNM, CASENT 0627829]; same data but 15.69116 −86.86075 ± 20 m ( LLAMA Wa-C- 09-2-20) [ ICN, CASENT 0627834].

Geographic range. southern Mexico, Guatemala, Honduras, Nicaragua.

Diagnosis. Differing from the similar A. longinoi in (1) more sharply differentiated anterior and dorsal face of pronotum in profile; and (2) posterior margin of postpetiole with sharp projecting transverse rim.

Description. Worker. HW 0.44–0.50 (n=5); mandible with differentiated masticatory and basal margins; masticatory margin with 5 teeth; basal margin sinuous with a distinct basal tooth and notch between tooth and condyle; dorsal surface of mandible with several coarse longitudinal striae and several large piligerous puncta; in full face view, lateral clypeal teeth small but still projecting from beneath clypeal shelf; lateral clypeal teeth located on anterior (ventral) margin of clypeus and separate from transverse carina that forms clypeal shelf; hypostomal tooth a minute triangular denticle; compound eye composed of 1–4 ommatidia; face coarsely reticulate rugose, with weak longitudinal orientation.

Short anterior face of pronotum meeting dorsal face at nearly right angle, separated by a low, simple transverse ruga; promesonotum evenly and very shallowly convex; metanotal groove weakly impressed; propodeal spines pronounced, triangular, acute at tip; space between propodeal spines a broad concavity without distinct dorsal and posterior faces, smooth and shiny with a moderately strong transverse ruga between propodeal spines, a few weaker rugulae above it; sculpture of dorsal promesonotum and side of mesosoma reticulate rugose like face; petiolar node relatively tall with differentiated anterior, dorsal, and posterior faces, rugose; postpetiolar node low and rounded, rugose laterally, smooth and shiny dorsally; in profile, postpetiolar node with a pronounced posteroventral rim; postpetiole in dorsal view about as long as wide, evenly rounded posteriorly; gastral dorsum smooth and shining.

Scape with abundant subdecumbent pubescence, and with two long suberect setae that are differentiated from the pubescence and project above it; clypeus and frontal carinae with long erect setae; posterior and posterolateral margins of head with long erect setae; mid and hind tibia with abundant long subdecumbent setae and 2–3 differentiated erect setae that are longer than width of tibia; in profile, dorsal surfaces of head, mesosoma, and gaster with relatively short, dense subdecumbent setae; FSH about 0.03, FSI 0.06.

Head and mesosoma red, gaster lighter yellow red.

Queen. Similar to worker except for queen-specific characters of large compound eyes, ocelli, and enlarged mesosoma with queen-typical sclerites; pronotum weakly reticulate rugose medially, coarsely reticulate rugose laterally; dorsal mesonotum smooth and shiny medially, grading into concentric rugulae peripherally; scutellum more coarsely reticulate rugose; katepisternum, anepisternum, and side of propodeum rugose, rugae somewhat more longitudinally oriented than on lateral pronotum.

Biology. This species is known from lowland rainforest sites, from sea level to 400 m elevation. All records are from Winkler samples of sifted litter. It is typically rare, but at one Honduran site it occurred in 17% of miniWinkler samples.

Comments. This species is very similar to A. longinoi . Character differences are subtle yet consistent across a broad zone of sympatry in Guatemala, Honduras, and Nicaragua. See further discussion under A. longinoi .

Etymology. Referring to the posterior rim of the postpetiole.

Figures

FIGURE 3. Profile of (A) Adelomyrmex longinoi and (B) A. marginodus.

FIGURE 16. Adelomyrmex marginodus sp. nov., holotype (Honduras, CASENT 0627826). Scale bars are 0.5 mm for face and dorsal views, 1.0 mm for lateral view.

FIGURE 21. Distribution of material examined in this study: Adelomyrmex anxiocalor sp. nov., A. betoi, A. bispeculum sp. nov., A. brenesi, A. laevigatus, A. mackayi, A. marginodus sp. nov., A. metzabok sp. nov., A. micans, A. microps, A. minimus, A. paratristani sp. nov., A. quetzal sp. nov., A. tristani.