Pogonomyrmex mendozanus Cuezzo and Claver 2009
Pogonomyrmex mendozanus Cuezzo
and Claver, 2009: 101, figs. 1, 2, 5-11 (worker, queen, male). Holotype worker: not examined [IADIZA], ARGENTINA, Mendoza:
Departamento Santa Rosa, Ñancuñán
(S. Claver leg., 12 Feb. 1997).
Pogonomyrmex pronotalis: Claver & Fowler 1993: 191 (nec Santschi);
Pirk et al., 2004: 65 (nec Santschi);
Pirk & Lopez de Casenave
2006: 119 (nec
Santschi); Pirk, et al.,
2007: 1092 (nec
Santschi); Pol & Lopez
de Casenave 2004: 647 (nec Santschi);
Pol, et al., 2008: 92 (nec Santschi);
Pirk, et al., 2009: 908 (nec Santschi).
Worker
Diagnosis. Within the P. laticeps-group,
the combination of: (1) head and mesosoma black, gaster a dark ferruginous orange, and (2) head and mesosoma covered by
fine, regular rugae uniquely characterize this
species.
Measurements
- (n = 16). HL 1.65-2.04; HW 1.87-2.28;
MOD 0.37-0.49; OMD 0.47-0.67; SL 1.25-1.59;
Description. Head slightly to moderately wider than long (CI = 102.50-113.33), widest
just posterior to eyes; posterior margin flat to weakly concave in full-face
view. Dorsal surface
of head with fine, regular, longitudinal cephalic rugae,
in full-face view median rugae diverging weakly toward
posterior corners of head. In side view, rugae posterior to eyes
converging toward vertex; vertex rugose. Cephalic interrugal spaces appearing as furrows, weakly to
moderately coriarious, weakly shining. Anterior margin of clypeus weakly
to moderately concave; dorsal surface with numerous subparallel
longitudinal rugae. Mandible with six teeth; mandibular
dorsum coarsely striated. Numerous long,
curved, bristle-like, yellowish to brownish hairs project from anterior margin
of clypeus and basolateral margin of mandibles. MOD ranging from 0.20-0.25x
HL. Eyes in profile situated near
middle of head, OMD = 1.24–1.43x MOD.
Antennal scapes relatively long (SI = 65.45-75.66),
reaching vertex or failing to reach vertex by less than length of basal
funicular segment; often with moderately coarse longitudinal striae. Basal flange
of scape flattened with carinate
margin. Psammophore
well developed.
Promesonotal profile
flattened to weakly irregular, propodeum descending; all
mesosomal surfaces with prominent subparallel/parallel
sculpturing similar to that on dorsum of head.
In side and dorsal views, humeral shoulders angulate, distinctly elevated above medial portion of pronotum. Dorsum of promesonotum with longitudinal rugae that diverge anteriorly
toward humeral angles; anterior margin of pronotum with
transverse rugae that traverse posteroventrally
or obliquely on pronotal sides. Mesopleura with transverse rugae, those near dorsal
margin often traversing posterodorsally. Dorsum and sides of propodeum with transverse rugae. Superior spines on propodeum
long, acuminate; spines longer than width between bases. Inferior propodeal spines absent or reduced to indistinct broadly
rounded process. Propodeal
spiracles narrowly ovate. Interrugal spaces on mesosoma
weakly coriarious, weakly shining to shining. Legs moderately coriarious, weakly shining.
Petiolar peduncle slightly
shorter than petiole, anteroventral margin usually
smooth, lacking tooth or lobe.
In side view, petiolar node broadly but
asymmetrically rounded with anterior surface shorter than posterior surface. Apex of node weakly angulate to rounded.
In dorsal view, petiolar
node longer than wide, widest anteriorly with spatulate anterior margin; dorsum with numerous fine
transverse to arc-shaped wavy striae that curve posteroventrally on sides. Dorsum of postpetiole
convex in profile; in dorsal view, widest near posterior margin, narrowing to
anterior margin; maximal width about equal to length; dorsum and sides with
numerous transverse wavy striae that are weaker, more
closely spaced than on petiole. Interrugal
spaces on petiole and post-petiole weakly to moderately punctate
or coriarious, weakly shining to shining. Dorsum of gaster weakly to moderately coriarious,
weakly shining to shining.
Erect
white pilosity moderately abundant on head, variable
in length, longest hairs not exceeding MOD.
Moderately abundant suberect to semidecument pilosity on scape, abundant decumbent hairs on funicular segments. Legs with moderately
abundant suberect white setae. Mesosoma, petiole, postpetiole with moderately
dense erect white setae, often similar in length, longest on pronotum, none exceeding MOD; gastral
terga with moderately dense pilosity,
only those on posterior gastral terga
approaching MOD. Head, mesosoma black; petiole dark orangish-brown to orangish-black;
postpetiole, gaster lighter
orangish-brown; mandibles, circumference of eyes, tarsi
often dark reddish-brown.
Brachyterous Queen
Diagnosis. This caste is diagnosed by: (1) brachypterous, (2) in dorsal view, mesoscutum
poorly developed, anterior margin barely surpassing humeral shoulders, (3) in
lateral view, pronotum meeting mesoscutum
at a shallow angle (approximately 45o), and (4) fine, regular,
longitudinal rugae on head, mesoscutum,
mesoscutellum, transverse rugae
on pronotum.
Measurements
- (n = 1). HL 2.53; HW 2.81; MOD 0.53;
OMD 0.81; SL 1.74; PNW 1.68; HFL 2.48; ML 2.76; PW 0.77; PPW 1.05. Indices: SI 61.92;
CI 111.07; OI 18.86; HFI 88.26. See also Cuezzo
& Claver (2009).
Ergatoid Queen
Diagnosis.
Measurements
–
Description.
Male
Diagnosis. This caste
is diagnosed by: (1) first gastral tergum lacking striae, (2) subparallel rugae prominent on
head and mesosoma, and (3) rugae
forming circumocular whorls posterior to eyes.
Measurements - (n = 12). HL 1.27-1.67; HW 1.44-1.68; MOD
0.46-0.56; OMD 0.23-0.40; SL 0.37-0.56; HFL 1.53-2.19; ML 2.47-2.91; PW
0.50-0.60; PPW 0.70-0.79. Indices: SI
23.42-34.15; CI 98.16-113.39; OI 29.34-33.94; HFI 106.25-133.54.
Additional material examined. ARGENTINA: Mendoza: Reserva Nancuñan, 1800’, Dec. 12,
2003 (RAJC; CASC); 115.0 km S Jct Rts
7 & 153, 1730’, Jan. 23, 2008 (RAJC); 138.1
km S Jct Rts 7 & 153,
1690’, Jan. 23, 2008 (RAJC); 22.1 km S Jct Rts 7 & 153, 1900’, Jan.
23, 2008 (RAJC); 38.4 km S Jct
Rts 7 & 153, 1870’, Jan. 23, 2008 (RAJC); Rt 171 at 15.0 km SE Monte Coman,
1700’, Jan. 27, 2008 (RAJC); Rt 7 at 10.3 km E La
Paz, 1540’, Jan. 23, 3008 (RAJC); Rt 7 at 9.8 km E La
Dormida, 1720’, Jan. 23, 2008 (RAJC); Rt 7 at 29.8 km E La Dormida,
1610’, Jan. 23, 2008 (RAJC); Rt
7 at 5.8 km W Desaguadero, 1530’, Dec. 28, 2005 (RAJC);
20 mi SE Mendoza, Dec. 26, 2006 (CSC); 8.5 km NW Real de Padre, Nov. 22, 2005
(CSC). San Juan: Nueva Castilla, Dec. 1964 (MZUSP); Pie de Palo,
Mar. 11, 1920 (LACM).
Etymology. The
specific epithet, mendozanus
(Latinization of Mendoza), is derived from the type
locality occurring in
Discussion. Pogonomyrmex mendozanus was misidentified
as P. pronotalis
in a list of ant species in Ñancuñan Biosphere
Reserve (Claver &
Fowler, 1993), and in subsequent
publications (see above) until it was described by Cuezzo
& Claver (2009). However, these two species are easily separated
with coloration one of few characters shared by both species. In describing P. mendozanus, Cuezzo
& Claver (2009) listed several characters to distinguish it from P. pronotalis. Sculpturing on the head and mesosoma is the best character: sculpturing on P. mendozanus
is relatively fine and very regular, whereas it is irregular on P. pronotalis.
The fine,
very regular sculpturing on the head and mesosoma of P. mendozanus is
also unique among all other congeners in Argentina, such that it is difficult
to misidentify P. mendozanus. Pogonomyrmex granulatus and P.
catanlilensis
are the only congeners that might be confused with P. mendozanus because of their similar
coloration. Both species are diagnosed by:
(1) irregular sculpturing on head and mesosoma, and (2)
very fine striae on first gastral
tergum. In P. mendozanus,
sculpturing on the head and mesosoma is very fine and
regular, and the first gastral tergum
lacks striae.
REFERENCES