Pogonomyrmex micans Forel 1914
Pogonomyrmex bruchi Forel r. micans Forel, 1914: 268 (worker,
male). Syntypes examined: 26 workers, 2 males [MHNG], 2 workers
[MLPA], #224, ARGENTINA, San Luis: Alto Pencoso near
La Plata (Bruch leg.). See also
Gallardo, 1932: 158, fig. 40 (MLPA worker here designated LECTOTYPE).
Pogonomyrmex micans Forel; Kusnezov,
1951: 254. Raised to species.
Worker
Diagnosis. Within the P. coarctatus-group, the combination of:
(1) entire head with very fine, dense longitudinal rugae,
weakly shining (2) coarse rugae on posterior surface
of petiole, rugae less coarse and more dense on
dorsum of postpetiole, (3) in side view, lateral lobe
of clypeus poorly developed with broad gap between clypeal lobe and frontal
carina (gap as wide to wider than antennal scape), and
(4) bicolored, head reddish-brown; mesosoma, petiole, postpetiole reddish-brown
to blackish-red; gaster reddish-brown to nearly black
uniquely characterize this species.
Measurements
- lectotype (n = 20). HL 2.09
(2.02–2.64); HW 2.25 (2.10–2.80); MOD 0.45 (0.42-0.56); OMD 0.41 (0.40–0.60);
SL 1.48 (1.23-1.73);
Description. Monomorphic, head
slightly wider to wider than long (CI = 102.65-112.44), widest just posterior
to eye; posterior margin flat to weakly concave in full-face view. Longitudinal rugae very fine and dense over entire head, width of rugae and interrugae similar; in
full-face view median rugae not diverging toward
posterior corners of head. Vertex
smooth and shining, or with very fine, dense rugae, interrugal spaces smooth, weakly shining to shining. Cephalic interrugal
spaces dull to weakly shining. In full-face view, head with silky appearance. Anterior margin of clypeus concave; dorsal
surface with numerous moderately coarse subparallel,
longitudinal to oblique rugae. Numerous long, curved, bristle-like,
yellowish macrochaetae project
from anterior margin of clypeus and ventral surface of mandibles. Mandible with six teeth, rarely with an
additional denticle between 4th and 5th
teeth; mandibular dorsum strongly striated. MOD ranging from 0.17–0.23x
HL. Eyes in profile situated
anterior to middle of head, OMD = 0.88–1.13x MOD. Antennal scapes
short (SI = 52.50–63.84), extending beyond posterior margin of eye by less than
length of first two funicular segments.
Base of antennal scapes smooth and shining, distal
portion weakly striated, weakly shining to strongly shining; basal flange well
developed with carinate margin. Psammophore
moderately well developed.
Mesosomal profile weakly
to moderately convex; all mesosomal surfaces with
prominent coarse, subparallel, slightly irregular,
widely spaced rugae.
In dorsal view, humeral portion of pronotum
rounded to knoblike. Dorsum
of promesonotum with longitudinal rugae
that diverge anteriorly toward humeral angles;
transverse rugae on anterior face of pronotum continue obliquely or longitudinally on pronotal sides; rugae on mesopleura angle posterodorsally. Superior propodeal
spines long, acuminate, connected by well-defined keel; spine length about
equal to width between bases; regular to slightly wavy transverse rugae on propodeal dorsum
traverse ventrally or anteroventrally on sides. Inferior propodeal
spines wider than long, apex rounded to angulate. Propodeal spiracles narrowly ovate.
Interrugal spaces on mesosoma
weakly to moderately granulate, weakly shining to shining. Legs weakly granulate, weakly shining.
Petiolar
peduncle about 0.8x as long as petiole, anteroventral margin with broadly rounded process. In side view, posterior surface of petiole weakly
convex; petiolar node asymmetrical with anterior surface
notably shorter than posterior surface, apex of node narrowly rounded to
ovate. In dorsal view,
petiole longer than wide, widest near middle, narrowing to spatulate
to weakly acute anterior margin.
Sides and posterior face of petiole with coarse, wavy to irregular
transverse rugae.
Dorsum of postpetiole convex
in profile; in dorsal view, widest near posterior margin, narrowing to anterior
margin, maximum width about equal to length. Regular to wavy, fine, dense transverse rugae on dorsum of postpetiole,
sometimes lacking on anterior margin; interrugal
spaces on petiole and postpetiole weakly to
moderately granulate, dull to weakly shining.
Dorsum of gaster moderately coriarious, weakly shining to smooth and shining.
Erect white to yellowish pilosity moderately abundant on head, variable in length
and arising from foveae; longest hairs not exceeding MOD, few exceeding 0.5x
MOD. Moderately
abundant suberect pilosity
on scape; abundant decumbent hairs on funicular
segments. Legs
with moderately abundant suberect to decumbent setae. Mesosoma, petiole, postpetiole, first gastral tergum with moderately dense erect setae that are similar
in length, longest hairs shorter than MOD; long hairs on margins of posterior gastral terga, occasionally
longer than MOD. Head
reddish-brown; mesosoma, petiole, postpetiole
reddish-brown to blackish-red; antennae, legs, gaster
reddish-brown to nearly black.
Queen
Diagnosis. As in
worker diagnosis, but with caste-specific morphology of the mesosoma
related to wing-bearing, presence of small ocelli on head,
and as illustrated in Figure x. This
caste is diagnosed by: (1) large size (HW = 2.94-3.09 mm), (2) fine rugae covering entire dorsum of head, and (3) in lateral
view, lateral lobe of clypeus not enlarged with broad gap (similar to the width
of antennal scape) between clypeal lobe and frontal
carina.
Measurements
- (n = 7). HL 2.50-2.84; HW
2.94-3.09; MOD 0.55-0.64; OMD 0.59-0.64; SL 1.52-1.68; PNW 2.01-2.23; HFL
2.20-2.47; ML 3.46-3.62; PW 0.77-0.91; PPW 1.04-1.19. Indices: SI 49.19-55.08; CI 108.10-122.13; OI
18.71-20.85; HFI 71.66-80.98.
Description. As in
worker diagnosis, but with caste-specific morphology of the mesosoma
related to wing-bearing, presence of small ocelli on
head, and as illustrated in Figure x.
Large species (HW = 3.94-3.09 mm); in full face view, head wider than
long (CI = 108.1–122.1), posterior margin weakly concave medially. Longitudinal rugae very fine and dense over entire head; striae on vertex often less abundant or absent. Interrugal spaces weakly shining to shining. Mandible with six teeth,
dorsal surface coarsely rugose. Psammophore
moderately well developed.
All mesosomal surfaces with subparallel,
weakly irregular rugae. Superior propodeal spines short. Petiolar peduncle slightly shorter than petiole, anteroventral
margin with blunt to angulate process. In side view, petiolar
node asymmetrical with anterior surface notably shorter than posterior surface,
apex of node rounded. Postpetiole
slightly wider than long. Posterior surface of petiole and dorsum of postpetiole
with wavy to irregular transverse rugae, rugae coarser on petiole than postpetiole;
interrugal spaces weakly punctate,
weakly shining. Gastral terga smooth, weakly shining
to shining. Most body surfaces with
moderately abundant suberect to erect, short white to
yellowish setae. Head
reddish-brown; mesosoma, petiole, postpetiole
reddish-brown to blackish-red; gaster reddish-brown
to nearly black.
Male
Diagnosis. This caste is diagnosed by: (1) hairs on head
(especially posterior to eyes) and dorsum of mesosoma
moderately long and flexuous, longest rarely exceeding 0.5-0.8x MOD, (2) rugae on head weak, usually irregular to rugoreticulate, interrugal spaces
dull, and (3) hairs white.
Measurements
- (n = 12). HL 1.67-1.95; HW
1.82-2.11; MOD 0.59-0.68; OMD 0.20-0.38; SL 0.44-0.56; PNW 1.64-1.99; HFL
1.81-2.20; ML 2.99-3.49; PW 0.68-0.83; PPW 0.82-1.02. Indices: SI 22.34-29.26; CI 100.00-126.35; OI
30.41-35.29; HFI 95.90-115.51.
Additional material examined. ARGENTINA: Córdoba: Rt 34 at Minas Clavero,
3005’, Dec. 18, 2006 (RAJC); 2.6 km N Nono, Dec. 19,
2006 (CSC); 5 mi N Deán Funes,
Feb. 8, 1951 (CASC). La Rioja: 4.2 km S Jct Rts 79 & 73, 1620’, Jan.
22, 2006 (RAJC); Rt 38 at 8.1 km W of Córdoba-La
Rioja border, 710’, Jan. 14, 2010 (RAJC); Rt 38 at
9.2 km E Chamical, 1500’, Jan. 14, 2010 (RAJC); Rt 79 at 1.5 km S Catuna, 1610’,
Jan. 22, 2010 (RAJC); Rt 79 at 34.6 km S Catuna, 2050’, Jan. 22, 2006 (RAJC); Rt 79 at 6.9 km SE Ulapes,
1250’, Jan. 22, 2006 (RAJC). Mendoza: Rt 7 at 5.8 km W Desaguadero, 1530’, Dec.
28, 2005 (RAJC); no loc., no date (MACN). Salta:
Lumbreras, no date (LACM); Piedras, no date (USNM). San Luis: La Punta, 2790’, Mar. 6, 2005; Dec. 27, 200 (RAJC); Rt 20 at 1
km NE Luján, 1940’, Dec. 26, 2005 (CASC; RAJC); Rt 20 at 38.8 km W Luján, 2030’, Dec.
27, 2005 (RAJC); Rt 20 at 75.6 km W Luján, 1570’, Dec. 27, 2005 (CASC; RAJC); Rt 20
at 1 km SW Quines, 1670’, Dec.
26, 2005 (RAJC); 3.7 km SE Jct Rts
20 & 147, 2380’, Dec. 27, 2005 (RAJC); Rt 7 at Alto Pencoso, 2330’, Dec. 27, 2005; Dec. 20, 2006
(RAJC); Rt 7 at 3.5 km W Alto Pencoso,
Dec. 19, 2006 (CSC); 38.8 km N Jct
Rts 20 & 79, 1240’, Jan. 22, 2006 (RAJC); no loc.,
no date (MACN; MLPA; USNM). Santa Fe: Ruta 34 at 3 km W Santa
Ana, 145m, Dec. 20, 2004 (RAJC). Tucumán: Ticucho, Dpto Trancas, Nov. 6,
1965 (MZUSP). PARAGUAY: Boquerón:
Ruta Trans-Chaco, 180m, Dec.
4, 2002 (ALWC).
Etymology. The specific epithet, micans (from Latin,
micans =
shining, gleaming, or sparkling), apparently refers to the head, which Forel
described as subopaque with a silky aspect.
Discussion. Pogonomyrmex micans co-occurs
with P. coarctatus,
and it is likely to co-occur with P. lobatus. Pogonomyrmex micans is
distinguished from P. coarctatus
using the following characters: (1) P. micans has very fine, dense longitudinal rugae over entire head, (2) dorsum of postpetiole
has prominent moderately coarse rugae, and (3)
workers are bicolored (dark red and blackish). In P. coarctatus, the very fine, dense longitudinal rugae are often indistinct and only cover part to most of head,
and (2) dorsum of postpetiole is weakly to moderately
granulate-punctate, occasionally with weak rugae near posterior margin, and (3) the entire body is
mostly concolorous reddish-orange to
reddish-brown. In P. lobatus: (1) the lateral lobe of clypeus
is massively enlarged, nearly contacting frontal carina, (2) dorsum of postpetiole weakly to moderately granulate, rarely with
weak transverse rugae posteriorly,
and (3) workers are concolorous reddish-orange to
reddish-brown. In P. micans: (1) the lateral lobe of clypeus
not enlarged, (2) the dorsum of postpetiole has
prominent moderately coarse rugae, and (3) workers
are bicolored (dark red and blackish). Pogonomyrmex marcusi is only known from mid- to higher elevation
areas of central Bolivia and thus is geographically isolated from P. micans; these two species can be
separated using characters in the key.
REFERENCES