Pogonomyrmex sylvestris Lattke 1991
Pogonomyrmex sylvestris Lattke, 1991: 305, figs. 1,
2 (worker). Types examined: none examined,
Worker
Diagnosis. Within the
P. sylvestris-group, the combination of: (1) six mandibular teeth, (2) eyes with hairs between ommatidia, (3) in lateral view, anterior margin of postpetiole not meeting helcium
at smooth continuous angle, (4) procoxa finely
imbricate in lateral view, and (5) femur and tibiae very strongly coriarious, dull, uniquely characterize this species.
Measurements
– (n = 4). HL 1.24-1.32; HW
1.16-1.20; MOD 0.20-0.21; OMD 0.30-0.32; SL 0.88-1.03; PNW 0.81-0.84; HFL
1.13-1.34; ML 1.51-1.61; PW 0.21-0.21; PPW 0.42-0.46. Indices: SI 73.95-86.44; CI 90.91-94.40; OI 16.67-17.80;
HFI 94.17-113.56. See also Lattke (1991).
Description. Head slightly elongate (CI = 90.91-93.55),
widest just posterior to eye; posterior margin weakly concave. Cephalic dorsum rugoreticulate except for several medial, irregular,
longitudinal rugae that become rugoreticulate
near posterior margin; vertex rugoreticulate. Cephalic interrugal
spaces smooth, shining. Anterior margin of clypeus weakly convex with small medial tooth,
dorsal surface with several subparallel longitudinal rugae. Mandible with six teeth; mandibular dorsum coarsely striated. Up to several moderately
long, curved, bristle-like, yellowish hairs project from anterior margin of
clypeus. Eyes small, MOD = 0.15-0.16x HL.
Eyes in profile situated anterior to middle of head, OMD = 1.50-1.55x
MOD; several short, delicate hairs project from between ommatidia. Antennal scapes
moderately long (SI = 82.76-83.74), failing to reach vertex by less than length
of basal funicular segment; entire scape with scattered
weak, longitudinal striae, strongly granulate-punctate, dull. Basal
flange of scape well developed with carinate margin. Psammophore
poorly developed, consisting of numerous short hairs (length similar to those on
cephalic dorsum) scattered across ventral side of head.
Mesosomal profile
strongly convex; all mesosomal surfaces rugoreticulate to vermiculate. Propodeum with long acuminate superior propodeal
spines, bases not connected by well defined keel, spines slightly shorter than
distance between bases. Inferior propodeal spines well-developed
with an acute tip, length similar to that of superior spines but with wider
base. Interrugal
spaces on mesosoma moderately granulate, sub-shining
to smooth, shining. Propodeal spiracles prominent,
circular. In
lateral view, procoxa finely imbricate, dull. Legs strongly granulate-punctate, dull.
Petiolar peduncle
about 0.6x as long as petiole, medioventral
margin with long acuminate spine. In
side view, petiolar node asymmetrical with anterior
surface about 0.5x as long as posterior surface, apex of node forming a crest
or tooth that is elevated above posterior surface; posterior surface flattened
to weakly convex; anterior and lateral surfaces mostly smooth and shining;
lateral surface nearly vertical, meeting posterior surface at near a right
angle. In dorsal view, petiolar node elongate (length > 2.3x width), margins
darkened, sides subparallel, weakly constricted near
posterior margin, anterior one-third narrowing to a subangulate
tip; dorsum coarsely rugoreticulate, interrugal spaces smooth and shining. Dorsum of postpetiole
convex in profile, anterior margin with subangulate
tip that overhangs connection to helcium; robust in
dorsal view, nearly triangular, widest near posterior margin, narrowing to
bluntly rounded anterior margin; lateral margins wider ventrally; dorsum
moderately to strongly coriarious to moderately
granulate, weakly shining, with several weak longitudinal rugae
near anterior margin. First
gastral tergum weakly coriarious, weakly shining to smooth and shining.
Short to
long, erect, yellowish to golden hairs abundant on head; medium to long hairs abundant
on mesosoma, petiole, postpetiole,
dorsum of gaster; longest hairs on head and mesosoma > MOD. Scape with
abundant moderately long suberect hairs; abundant
decumbent hairs on funicular segments.
Legs with moderately abundant, long, suberect setae.
Head and mesosoma dark brown;
petiole, postpetiole, gaster,
legs slightly lighter brown to tan.
Queen.
Unknown.
Male.
Unknown.
Additional material examined.
Etymology. The specific epithet, sylvestris (sylva - Latin for forest), was
derived from the type series being collected in cloud forest (premontane rain) habitats in
Discussion. Pogonomyrmex sylvestris might co-occur with P. striatinodis
and P. naegelii. Both of the former species occur in mesic forest habitats, while P. naegelii occurs in open, drier
habitats. Pogonomyrmex sylvestris is distinguished from P. striatinodis
by: (1) several hairs between ommatidia, (2) the
clypeus lacks a medial carina, and (3) in lateral view, the anterior margin of postpetiole does not meet the helcium
at a smooth continuous angle; P. striatinodis lacks hairs between ommatidia,
the clypeus has a prominent medial carina, and in lateral view, the anterior
margin of postpetiole meets the helcium
at a smooth continuous angle.
Pogonomyrmex sylvestris is
distinguished from P. naegelii by: (1)
hairs between ommatidia, (2) an elongate, triangular postpetiole, and (3) in lateral view, the petiole is flattened to slightly convex with a crest on anterior
margin that is elevated above the posterior face. Pogonomyrmex naegelii lacks hairs between ommatidia,
the postpetiole is nearly globular with width and
length similar, and in lateral view, the petiole is
convex and lacks a crest on anterior margin.
BIOLOGY
See
discussion under P. stefani.
REFERENCES