Pogogonomyrmex pencosensis Forel 1914 NEW STATUS
Pogonomyrmex cunicularius Mayr race pencosensis Forel, 1914: 265 (worker,
male). Syntypes examined: 24 workers, 1 ergatoid queen, 1 male [MHNG], 1 worker [MLPA], #1555,
Pogonomyrmex cunicularius pencosensis var. dubia Forel, 1914: 267 (worker). Syntypes
examined: 1 worker [MHNG], 1 worker [MLPA],
Worker
Diagnosis. Within the P. cunicularius-group, the combination of:
(1) in lateral view, apex of petiolar
node weakly rounded to angulate, (2) inferior propodeal spines acuminate, (3) superior propodeal spines long, length notably greater than distance
between bases, (4) first gastral tergum
moderately coriarious, dull to weakly shining, (5) sculpturing
on dorsum of mesosoma and posterior face of petiole
weak to moderately strong, rugae irregular to moderately
rugoreticulate, and (6) entire body concolorous tannish-red uniquely
characterize this species.
Measurements
- lectotype (n
= 12). HL 1.88 (1.79-2.27); HW 1.51 (1.57-1.95); MOD 0.30 (0.31-0.40);
OMD 0.41 (0.44-0.63); SL 1.43 (1.35-1.85); PNW 0.95 (1.10-1.31); HFL 2.30 (2.21-2.78);
ML 2.22 (2.30-2.82); PW 0.38 (0.39-0.47); PPW 0.54 (0.51-0.63). Indices:
SI 94.70 (79.26-98.92); CI 80.32 (81.53-88.27); OI 19.87 (17.84-22.70); HFI
152.32 (130.85-151.38).
Description. Head elongate (CI = 80.32-88.27), widest
immediately posterior to mandibles, narrowing posterior to eyes and forming a
broadly rounded vertex; posterior margin flat to weakly convex in full-face
view. Dorsum of head with weak to moderately
strong longitudinal, wavy to irregular rugae or
weakly rugoreticulate, often weaker to indistinct
near posterior margin; in full-face view median rugae
diverging only slightly towards posterior corners of head. Vertex weakly to moderately rugose, or granulate, dull to weakly shining. Cephalic interrugal
spaces weakly to strongly granulate, dull to sub-shining. Anterior margin of clypeus
flat; dorsal surface with more than several subparallel
longitudinal or oblique rugae. Mandibles with six teeth; mandibular
dorsum coarsely striated. Eyes small, MOD ranging from 0.15–0.19x HL. Eyes in profile, situated anterior to middle
of head, OMD = 1.19-1.80x MOD; in full-face view, eyes protruding beyond
lateral margins of head. Antennal scapes long (SI = 79.26-98.92), surpassing vertex by less
than length of first funicular segment; entire scape
with longitudinal striae. Basal flange of scape well-developed with carinate
margin. Psammophore
poorly developed, consisting of short to medium-length hairs scattered across ventral
surface of head.
Promesonotal profile weakly convex, propodeum flat; all
mesosomal surfaces with subparallel
irregular rugae to weakly rugoreticulate. In dorsal view, humeral portion of pronotum rounded. Dorsum of promesonotum with transverse or
oblique, irregular rugae to reticulate, weaker or
mostly absent and weakly to moderately granulate on pronotal
sides; mesopleura with irregular rugae
that angle posterodorsally. Propodeal spines
long, strongly tapered to an acute tip, notably longer than width between
bases; spines connected by well-defined keel; irregular transverse rugae on propodeal dorsum traverse
ventrally or anteroventrally on sides. Inferior propodeal spines well-developed, triangular, wider than
high, with an angulate to acute tip. Propodeal spiracles narrowly ovate.
Interrugal spaces on mesosoma
smooth to moderately granulate, weakly to strongly shining. Legs long (HFL = 2.21-2.78 mm), strongly coriarious to granulate, dull.
Petiolar peduncle about as long as petiole, anteroventral
margin with an acuminate spine.
In side view, petiolar node asymmetrical with
anterior surface notably shorter than posterior surface; apex of node weakly
rounded to angulate, usually weakly elevated above
the flattened posterior face of petiole.
In dorsal view, petiolar node about 1.5x longer than wide, widest near weakly to moderately
acute anterior margin. Sides and posterior face of petiole with irregular transverse rugae, rugoreticulate, or
granulate-punctate. Dorsum of postpetiole
convex in profile; in dorsal view, widest near posterior margin, narrowing to
anterior margin, slightly longer than wide, strongly granulate-punctate, dull to weakly shining. Dorsum of gaster
moderately to strongly coriarious, dull to weakly shining.
Erect to semi-erect yellowish pilosity moderately abundant on head, variable in length,
longest hairs notably shorter than MOD. Moderately abundant suberect yellowish pilosity on scape; abundant
decumbent hairs on funicular segments.
Legs with moderately abundant subdecumbent
to decumbent white to yellowish setae.
Mesosoma, petiole, postpetiole, and dorsum of gaster with moderately dense erect setae, mostly similar in
length, longest hairs not exceeding MOD.
Entire body concolorous tannish-red, often with darker transverse bands on gastral terga.
Queen
Diagnosis. Ergatoid, with
small ocelli on head; otherwise as in worker
diagnosis, and as illustrated in Figure x.
This caste is diagnosed by: (1) anterior margin of clypeus flat to weakly
convex, apron lacking clypeal teeth, (2) in lateral view, node of petiole angulate, (3) inferior propodeal
spines about as wide as high with an acute tip, (4) first gastral
tergum moderately coriarious,
dull to weakly shining, and (5) sculpturing on dorsum of mesosoma
and posterior face of petiole weak to moderately strong, rugae
irregular to moderately rugoreticulate.
Measurements - (n = 12). HL 2.24-2.58; HW 1.99-2.26; MOD 0.38-0.43; OMD 0.51-0.65;
SL 1.70-1.91; PNW 1.27-1.50; HFL 2.45-2.86; ML 2.62-3.13; PW 0.45-0.57; PPW
0.68-0.82. Indices: SI 77.63-86.93; CI 85.78-92.41;
OI 16.81-21.61; HFI 108.41-143.72.
Description. Ergatoid; mesosomal segments fused, occasionally with weakly
impressed promesonotal and/or mesoepinotal
suture, lacking all morphological structures related to wings or for inserting wings.
All mesosomal
surfaces with subparallel, wavy to weakly irregular rugae. Propodeum with long superior spines; spines much longer
than width between bases; inferior propodeal spines
well-developed, triangular, wider than high, with an angulate
to acute tip. Petiolar peduncle about as long as
petiole, anteroventral margin with an acute
spine-like process. In side view,
petiolar node asymmetrical with
anterior surface notably shorter than posterior surface, apex of node angulate. Posterior face of petiole with wavy to moderately irregular
transverse rugae; interrugal
spaces weakly punctate, weakly shining. Postpetiole convex in profile; in dorsal view, maximum width about equal to
length; dorsum moderately to strongly granulate-punctate
or with weak irregular transverse to oblique rugae,
dull to weakly shining. Dorsum of
gaster moderately to strongly coriarious,
dull to weakly shining.
Most body surfaces with moderately
abundant suberect to erect, short white to yellowish
setae. Body concolorous tannish-red, gaster often slightly darker with one or more darker
transverse bands.
Male
Diagnosis. This caste is diagnosed by: (1) legs long,
HFI > 130.0, (2) hairs yellowish-brown to brownish, (3) superior propodeal spines well developed, and (4) in lateral view, petiolar node sharply angulate.
Measurements
- (n = 12). HL 1.36-1.66; HW
1.10-1.44; MOD 0.50-0.62; OMD 0.18-0.33; SL 0.34-0.53; HFL 1.97-2.64; PW
0.44-0.63; PPW 0.62-0.89. Indices: SI 29.50-41.09; CI 80.88-97.96; OI 38.85-45.74; HFI
136.81-195.56.
Additional material examined. ARGENTINA: Catamarca: Jct Rts 46 &
60, 2830’, Jan. 17, 2006 (RAJC); Joyango, Dec. 30, 1973 (LACM; USNM); Villa Vil, Feb. 11, 1974
(LACM); Andagalá, Feb. 10, 1945 (USNM); Chumbicha, no date (MACN). Córdoba: Nono,
2940’, Jan. 17. 2008 (RAJC); Rt 20 at 1.0 km N Nono,
2920’, Jan. 23, 2006 (RAJC); 5 mi N Deán Funes, Feb. 8, 1951 (CASC); 24 mi S El Recreo, Feb. 9, 1951
(CASC); Alta Gracia, Apr. 1930 (MACN); Alta Gracia La
Granja, Sierras de Córdoba, no date (USNM); no
loc., no loc. (LACM; MACN; MCZ; MLPA). La Rioja: 30.8 km E Jct Rts 5 & 38, 1160’, Jan.
21, 2006 (RAJC); 36.3 km E Jct Rts
5 & 60, 1080’, Jan. 21, 2006 (RAJC); 4.2 km S Jct
Rts 79 & 73, 1620’, Jan. 22, 2006 (RAJC); 4.3 km SE Jct Rts 5 & 60, 960’, Jan. 21, 2006 (RAJC); 47.0 km SE Jct Rts 5 & 60, 850’, Jan. 21, 2006 (RAJC); 96.8 km N Jct Rts 9 & 38, 1750’, Jan. 7, 2006 (RAJC); Rt 38 at 24.7 km N La Rioja, 1400’, Jan. 7, 2006 (RAJC); Rt 38 at 15.8 km N Patquía, 1580’,
Jan. 20, 2006 (RAJC); 7.4 km N Jct Rts 38 & 74, 1490’, Jan. 15, 2010 (RAJC); Rt 38 at 8.1 km W of Córdoba-La Rioja border,
710’, Jan. 14, 2010 (RAJC); Rt 40 at 1.3 km W Los
Tambillos, 5240’, Jan. 3, 2006 (RAJC); Rt 40 at 6.0
km N Chilecito, 3200’, Jan. 3, 2006 (RAJC); Rt 40 at
11.3 km N Chilecito, 3230’, Feb. 6, 2010 (RAJC); Rt
40 at 14.0 km N Chilecito, 3410’, Feb. 4, 2010 (RAJC); Rt
40 at 49.1 km S Pituil, 4270’, Jan. 20, 2006 (RAJC); Rt 40 at 5.7 km SW Nonogasta,
3690’, Jan. 3, 2006 (RAJC); Rt 73 at 83.8 km NE Chamical, 1110’, Jan. 21, 2006 (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); Rt 40 at 30.0 km E Villa Unión, 4560’, Jan. 3, 2006 (CASC; RAJC);
no loc., no date (MACN). Mendoza: Rt
7 at 19.8 km E La Paz, 1520’, Jan. 23, 2008 (RAJC); Rt
7 at 5.8 km W Desaguadero, 1530’, Dec. 28, 2005
(RAJC). Salta: 50 km NE Joaquin
V. Gonzales, Mar. 4, 1992 (LACM). San
Luis: 3.7 km SE Jct Rts
20 & 147, 2380’, Dec. 27, 2005 (RAJC); La Punta,
2790’, Dec. 27, 2005 (RAJC); Parque Nacional Sierra
las Quijadas, 2610’ & 2720’, Mar. 6, 2005 (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 (RAJC); Rt 7 at
Alto Pencoso, 2330’, Dec.
27, 2005 (MACN; RAJC); no loc., no date (MLPA). Santiago
del Estero: Pampa de los Guanacos, 142m, Apr.
2009 (RAJC); Lago Muyo, Apr. 1957 (LACM). Tucumán:
9 km SSE Las Cejas, 330m, Feb. 4, 1995 (MCZ); Ticucho,
Dpto. Trancas, Dec. 1, 1965 (MZUSP); Saladillo, no
date (USNM); no loc., no date (USNM). Questionable
locales. Catamarca:
Agudos, Feb. 4, 1967 (MCZ).
Etymology.
The specific epithet, pencosensis (Latinization of Pencoso, and –ensis = adjectival suffix for belonging to), refers to the syntype series being collected at Alto Pencoso,
San Luis Province, Argentina.
Discussion. Pogonomyrmex pencosenis is not
known to co-occur with any other P. cunicularius-group species. However, additional collections may show that
it co-occurs with P. cunicularius and P. serpens (see distribution maps). Pogonomyrmex pencosensis can be distinguished from P. cunicularius
based on the following characters: (1) petiolar node
is angulate in profile, (2) superior propodeal spines longer than distance between bases, (3)
inferior propodeal spines about as wide as high with
an acute tip, and (4) first gastral tergum coriarious, dull to weakly
shining. In P. cunicularius, the petiolar
node is rounded in profile, superior propodeal spines
are shorter than the distance between bases, inferior propodeal
spines are wider than high, broadly rounded, and first gastral
tergum is smooth and polished, strongly shining. Pogonomyrmex pencosensis is distinguished from P. serpens based on the following
characters: (1) sculpturing on dorsum of the mesosoma
and posterior face of petiole weak, rugae irregular
to moderately rugoreticulate, and (2) body concolorous tannish-red. In P. serpens, the sculpturing on dorsum
of the mesosoma and posterior face of petiole is
coarse, rugoreticulate to vermiculate, and the body
is bicolored with mesosoma
and petiole orangish-brown to reddish-brown, the rest
slightly lighter.
In describing P. cunicularius race pencosensis, Forel indicated it to
be smaller and more slender, the sculpturing more dense, the head more dull, and
the inferior propodeal spines longer and more acute than
in P. cunicularius. Indeed, workers and ergatoid
queens of P. pencosensis are morphologically distinct
and easily distinguished from P. cunicularius and P.
serpens. Thus, I raise P. pencosensis from synonomy
to rank as a valid species.
REFERENCES