Adelomyrmex metzabok Longino

Longino, John T., 2012, A review of the ant genus Adelomyrmex Emery 1897 (Hymenoptera, Formicidae) in Central America, Zootaxa 3456, pp. 1-35 : 22-23

Adelomyrmex metzabok Longino , sp. nov.

( Figs 7 , 17 , 21 )

Type material. Holotype worker. Mexico, Chiapas: Lago Metzabok , 17.12614 −91.63061 ± 50 m, 570 m, 5 Jun 2008 ( LLAMA Wa-A- 06-1-14) [ CAS, unique specimen identifier CASENT 0627820]. Paratypes: Mexico, Chiapas: Laguna Metzabok , 17.12550 −91.63082 ± 50 m, 600 m, 14 Jul 2007 (J. Luna-Cozar) [ UCD, JTLC 000010100]; 13.7km NW Metzabok , 17.19052 −91.73748 ± 50 m, 540 m, 14 Jun 2007 (R. S. Anderson 2007- 012) [ECOSCE, CASENT 0601933]; Lago Metzabok , 17.12562 −91.63090 ± 50, 570 m, 5 Jun 2008 ( LLAMA Wa- A- 06-1-01) [ MCZC, JTLC 000014343]; Lago Metzabok , 17.12566 −91.63088 ± 50 m, 570 m, 5 Jun 2008 ( LLAMA Wa-A- 06-1-02) [ MZSP, JTLC 000014346]; Lago Metzabok , 17.12602 −91.63068 ± 50 m, 570 m, 5 Jun 2008 ( LLAMA Wa-A- 06-1-11) [ USNM, JTLC 000014355]; same data as holotype [ BMNH, CASENT 0627822], [ EAPZ, CASENT 0627821].

Geographic range. Southern Mexico, Guatemala.

Diagnosis. Differing from A. myops in (1) promesonotum strongly produced, higher at mesonotum than pronotum, steeply dropping to dorsal face of propodeum (lower and more evenly and shallowly convex in A. myops ); and (2) posterior faces of petiole and postpetiole each with dorsal transverse ruga, such that in profile nodes appear somewhat flat-topped and with posterior tooth (petiolar and postpetiolar nodes more rounded in A. myops ).

Description. Worker. HW 0.58–0.63 (n=6); mandible with differentiated masticatory and basal margins; masticatory margin with five or six teeth, apical three always large and distinct, decreasing in size, remaining two or three highly variable in degree of development; 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; lateral clypeal teeth large, in full face view 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 denticle; compound eye composed of 6–9 ommatidia; face fully sculptured with reticulate rugae, with weak longitudinal orientation medially.

Short anterior face of pronotum meeting dorsal face at obtuse angle, separated by a low, sometimes crenulated ruga; promesonotum robust, strongly produced, sloping up posteriorly, dropping abruptly to metanotal groove; propodeal spines triangular, acute; space between propodeal spines a broad concavity without distinct dorsal and posterior faces, smooth and shiny with a few transverse rugae; rest of mesosoma strongly reticulate rugose, rugae of dorsal promesonotum strongly wavy reticulate, with little longitudinal orientation; posterior faces of petiole and postpetiole each with dorsal transverse ruga, such that in profile nodes appear somewhat flat-topped and with posterior tooth; petiole and postpetiole coarsely irregularly rugose, postpetiole with smooth dorsum; postpetiole in dorsal view about as long as wide, triangular, with blunt posterior projection; gastral dorsum smooth and shining.

Scape with abundant long subdecumbent pubescence; 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 3–4 differentiated erect setae that are longer than width of tibia; in profile, dorsal surfaces of head, mesosoma, and gaster with relatively short, dense suberect setae; FSH about 0.08, FSI 0.13.

Color dark brown to black.

Queen. Similar to worker except for queen-specific characters of large compound eyes, ocelli, and enlarged mesosoma with queen-typical sclerites; pronotum smooth medially, reticulate rugose laterally; dorsal mesonotum with widely-spaced longitudinal rugae evenly covering surface with exception of small anteromedian smooth area; scutellum more coarsely reticulate rugose; katepisternum smooth and shining; anepisternum smooth ventrally, rugose dorsally; side of propodeum rugose.

Biology. Adelomyrmex metzabok occurs in mature and second growth wet forest habitats in the eastern lowlands of Chiapas and the eastern Petén region of Guatemala. Records are from sea level to just below 1000 m elevation. All records are from Winkler or Berlese extractions from sifted litter, with the exception of one occurrence at a bait. It can be locally abundant, occurring in up to 26% of miniWinkler samples. Queens occasionally occur together with workers in Winkler samples.

Etymology. Referring to the type locality.

Figures

FIGURE 7. Profile of (A) Adelomyrmex metzabok and (B) A. myops.

FIGURE 17. Adelomyrmex metzabok sp. nov., holotype (Mexico, CASENT 0627820). 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.