Temnothorax balaclava, Prebus, 2021

Prebus, Matthew M., 2021, Taxonomic revision of the Temnothorax salvini clade (Hymenoptera: Formicidae), with a key to the clades of New World Temnothorax, PeerJ (e 11514) 9, pp. 1-462 : 280-287

Temnothorax balaclava sp. nov.

Distribution: Fig. 133D ; worker & gyne: Fig. 138 .

Type material examined: Holotype worker: DOMINICAN REPUBLIC: Pedernales: Jaragua National Park , 18.02571 ° N 71.64732 ° W ± 5 m, 92 m, 1 April 2012, D. Lubertazzi #DL03474 , dry forest, downed wood ( CASENT0758262 ) [ MCZC].

Paratype workers & gyne: same data as holotype, 1 worker (CASENT0756153) [ UCDC] 2 workers (CASENT4010177) [ CASC] 2 workers (CASENT4010178) [ USNM] ; same data as previous, except: D. Lubertazzi #DL03476:001, dry forest, in soil under downed wood, 2 workers (CASENT4010179) [ LACM] ; same data as previous, except: D. Lubertazzi #DL03477:001, dry forest, under dead agave, 2 workers (CASENT4010180) [ MNHNSD] ; same data as previous, except: D. Lubertazzi #DL03477:002, dry forest, under dead agave, 2 workers (MCZENT00510544) [ MCZC] ; same data as previous, except: D. Lubertazzi #DL03477:003, dry forest, under dead agave, 2 workers (MCZENT00510545) [ MCZC] ; same data as previous, except: D. Lubertazzi #DL03477:004, dry forest, under dead agave, 1 dealate gyne (MCZENT00510546) [ MCZC] .

Non-type material examined: DOMINICAN REPUBLIC: Pedernales: Jaragua National Park , 17.792206 ° N 71.46109 ° W ± 5 m, 125 m, 26 March 2012, D. Lubertazzi #DL03383:003, xeric scrub on limestone, in soil and litter at base of tree, 1 worker (MCZENT00510535) [ MCZC] ; same data as previous, except: D. Lubertazzi #DL03388:001, xeric scrub on limestone, sifted soil and litter under half buried branch, 1 worker (MCZENT00510536) [ MCZC] ; same data as previous, except: 17.79249 ° N 71.46385 ° W ± 13 m, 126 m 30 March 2012, D. Lubertazzi #DL03411:001, dry forest, litter at base of large tree, 1 worker (MCZENT00510537) [ MCZC] ; same data as previous, except: Jaragua National Park access road, 17.78166 ° N 71.44007 ° W ± 8 m, 87 m 29 March 2012, D. Lubertazzi #DL03433:001, dry forest, under downed wood, 1 worker (MCZENT00510538) [ MCZC] ; same data as previous, except: Jaragua National Park , 18.02571 ° N 71.64732 ° W ± 9 m, 92 m 2 April 2012, D. Lubertazzi #DL03497:001, dry forest, downed wood, 2 workers (MCZENT00510548) [ MCZC] ; same data as previous, except: D. Lubertazzi #DL03497:002, dry forest, downed wood, 2 workers (MCZENT00510549) [ MCZC] ; same data as previous, except: 18.02571 ° N 71.64732 ° W ± 11 m, 92 m 31 March 2012, D. Lubertazzi #DL03501:001, dry forest, litter, 1 dealate gyne (MCZENT00510550) [ MCZC] 1 worker (MCZENT00510551) [ MCZC] ; same data as previous, except: #DL03501:003, dry forest, litter, 2 workers (MCZENT00510552) [ MCZC] .

Geographic range: Low elevations of Hispaniola ( Fig. 133D ).

Worker diagnosis: Temnothorax balaclava sp. nov. can be separated from all other species in the salvini clade by the following character combination: anterior clypeal margin evenly convex; in profile view, dorsum of mesosoma weakly convex; metanotal groove not impressed; propodeum not depressed below the level of the promesonotum; propodeum bearing standing setae dorsally; propodeal spines about as long as the propodeal declivity, and directed posterodorsally; in dorsal view, propodeal spines broadly approximated, the negative space between them “U” shaped; hind femora moderately incrassate; petiole 1.5 to 1.6 times the length of the postpetiole; in dorsal view, apex of petiolar node narrower to slightly broader than the caudal cylinder of the petiole; postpetiole very broad: greater than or equal to 2.4 times the width of the petiole; dorsum of head smooth and shining; petiolar node with four erect setae dorsally; setae on head, mesosoma, waist segments and gaster erect, moderately long, sparse and blunt (never long and tapering); integument bicolored: predominantly yellow, with the head capsule (excluding clypeus) and posterior third of the first gastral tergite dark brown.

Similar species: Temnothorax balaclava sp. nov., T. ciferrii , T. harlequina sp. nov., T. hippolytus sp. nov., T. magnabulla sp. nov., T. nigricans , T. pulchellus , T. schwarzi , T. terricola , and T. wilsoni sp. nov. The erect setae count of four on the dorsum of the petiolar node differentiates T. balaclava sp. nov. from T. terricola and T. hippolytus sp. nov., which have only two along the posterior margin. The presence of erect setae on the propodeum distinguishes T. balaclava sp. nov. from T. pulchellus . The relatively small metapleural gland bulla of T. balaclava sp. nov., which reaches halfway to from the metacoxal insertion to the propodeal spiracle, distinguishes it from T. magnabulla sp. nov., in which it extends three quarters of the way or more. Temnothorax balaclava sp. nov. and T. harlequina sp. nov. can be separated most easily by the color of the integument: T. harlequina sp. nov. has a light yellow gaster which strongly contrasts with the darker integument of the rest of the body, whereas the gaster, waist segments, and mesosoma and of T. balaclava sp. nov. is always light yellow, and the gaster bears a dark brown band across the posterior third of the gaster. The mesosoma is of T. balaclava sp. nov. is less arched and more densely sculptured in comparison to T. harlequina sp. nov. Temnothorax balaclava sp. nov. could also be confused with T. schwarzi due to the smooth and shining head capsule, but the relatively narrow apex of the petiolar node of T. balaclava sp. nov. will separate the two. Temnothorax nigricans is superficially similar due to the nearly identical integument coloring, but can be separated from T. balaclava sp. nov. by the areolate head sculpture and dorsally broader petiolar node. The medially rounded anterior clypeal margin of T. balaclava sp. nov. will differentiate it from T. wilsoni sp. nov. and T. bahoruco sp. nov., which have emarginate and flat anterior clypeal margins, respectively. Temnothorax balaclava sp. nov. can be further separated from T. bahoruco sp. nov. by the relatively longer petiole, which is 1.5 to 1.6 times the length of the postpetiole, versus 1.4 times in T. bahoruco sp. nov.

Worker measurements & indices (n = 7): SL = 0.407 –0.471 (0.434); FRS = 0.165 –0.212 (0.185); CW = 0.470 –0.559 (0.515); CWb = 0.425 –0.518 (0.473); PoOC = 0.201 –0.240 (0.220); CL = 0.511 –0.612 (0.559); EL = 0.121 –0.140 (0.130); EW = 0.093 –0.114 (0.105); MD = 0.114 –0.149 (0.130); WL = 0.561 –0.675 (0.614); SPST = 0.220 –0.247 (0.231); MPST = 0.194 –0.223 (0.207); PEL = 0.247 –0.299 (0.277); NOL = 0.131 –0.186 (0.161); NOH = 0.092 –0.116 (0.101); PEH = 0.161 –0.200 (0.178); PPL = 0.163 –0.202 (0.178); PPH = 0.190 –0.228 (0.207); PW = 0.315 –0.376 (0.342); SBPA = 0.130 –0.172 (0.150); SPTI = 0.135 –0.294 (0.216); PEW = 0.120 –0.155 (0.135); PNW = 0.118 –0.151 (0.135); PPW = 0.322 –0.375 (0.345); HFL = 0.399 –0.454 (0.430); HFWmax = 0.110 –0.127 (0.119); HFWmin = 0.042 –0.047 (0.045); CS = 0.681 –0.824 (0.752); ES = 0.171 –0.197 (0.182); SI = 86–96 (92); OI = 23–26 (24); CI = 83–87 (85); WLI = 126–133 (130); SBI = 29–34 (32); PSI = 35–39 (38); PWI = 242–268 (257); PLI = 148–166 (155); NI = 139–190 (160); PNWI = 94–109 (100); NLI = 52–63 (58); FI = 243–293 (268).

Worker description: In full-face view, head subquadrate, longer than broad (CI 83–87). Mandibles weakly striate, shining, and armed with five teeth: the apical-most well developed, followed by a less developed preapical tooth and three equally-developed smaller teeth. Anterior clypeal margin evenly convex. Antennal scapes moderately long: when fully retracted, just barely surpassing the posterior margin of the head capsule (SI 86–96). Antennae 12-segmented; antennal club of three segments, with the apical-most segment slightly longer than the preceding two in combination. Frontal carinae moderately long, extending past the antennal toruli by about two times the maximum width of the antennal scape. Compound eyes moderately protruding past the lateral margins of the head capsule. Lateral margin of head weakly convex, forming a continuous arc from the posterior of the head, converging below the compound eye to the mandibular insertions. Posterior head margin weakly concave to flat, rounding evenly into the lateral margins.

In profile view, compound eyes ovular and moderately large (OI 23–26), with 9 ommatidia in longest row. Pronotal declivity indistinct, neck and anterior face of pronotum forming a rounded ~120 ° angle. Mesosoma evenly convex dorsally from where it joins the pronotal neck to the propodeal spines. Promesonotal suture extending from the posterior margin of the procoxal insertion only to the mesothoracic spiracle, which is well developed. Metanotal groove visible as a disruption of the sculpture laterally from where it arises between the mid- and hind coxae to where it ends in the poorly developed metathoracic spiracle, which is nearly indistinguishable against the ground sculpture. Propodeal spiracle well developed, directed posterolaterally, and separated from the propodeal declivity by about two and a half spiracle diameters. Propodeal spines well developed and moderately long (PSI 35–39), about as long as the propodeal declivity, tapering evenly from the base, straight, and acute. Propodeal declivity straight and flat, forming a rounded ~90 ° angle with the base of the propodeal spines. Propodeal lobes rounded and weakly developed. Metapleural gland bulla small, extending from the metacoxal insertion halfway to the propodeal spiracle. Petiole moderately long (PLI 148–166), without tubercles anterodorsally. Subpetiolar process in the form of a weakly developed, acute tooth; ventral margin of petiole weakly concave posterior to it. Petiolar peduncle short: petiolar node covering most of the petiolar dorsum. Petiolar node robust: grading evenly into the petiolar peduncle anteriorly, anterior face weakly concave; anterior face forming a rounded, ~110 ° angle with the dorsal surface, which is weakly convex and nearly flat; dorsal surface rounding evenly into the short posterior declivity, which forms a ~100 ° angle with the caudal cylinder. Postpetiole evenly rounded dorsally, and weakly lobed ventrally.

In dorsal view, humeri weakly developed: evenly rounded and slightly wider than the rest of the mesosoma; mesothoracic spiracles weakly protruding past the lateral margins of the mesosoma, visible as slight angles where the pronotum meets the mesonotum. Metanotal groove absent: mesonotum and propodeum completely fused and converging evenly to the bases of the propodeal spines. Propodeal spines broadly approximated basally and diverging apically, their apices separated from each other by about their length; negative space between them “U” shaped. Petiolar peduncle with spiracles protruding past the lateral margins, peduncle slightly narrowed anterior to them. Petiolar node evenly ovular, but slightly flatted posteriorly; node slightly wider than the peduncle, and evenly grading into the caudal cylinder, which is the same width as the node. Postpetiole very broad (PWI 242–268) and campaniform, articulating with the nearly the entire anterior margin of the gaster. Anterior margin of the postpetiole weakly concave, evenly rounding into the lateral margins, which diverge to the angulate posterior corners; posterior margin broadly concave. Metafemur weakly to moderately incrassate (FI 243–293).

Sculpture: median clypeal carina present, extending posteriorly nearly to the frontal triangle, and flanked on either side by two equally strong carinae. Lateral clypeal lobes with additional, weaker carinae; ground sculpture smooth and shining. Antennal scapes shining through weak areolate ground sculpture. Cephalic dorsum smooth and shining, but with coarse piligerous punctures; costulae flanking the frontal carinae. Lateral surfaces of head with weak areolate sculpture posterior to the compound eye, dense rugose sculpture surrounding the compound eye, and weak rugae between the compound eye and the mandibular insertion. Ventral surface of head smooth and shining. Pronotal neck areolate. Lateral surface of the pronotum shining through weak costulae. Mesopleurae and anterior half of the lateral face of the propodeum areolate, but propodeum smooth and shining between the propodeal spiracle and the propodeal spines. Dorsal surface of mesosoma with weak costulae on the pronotum and lateral margins over areolate ground sculpture. Femora shining, with weak areolate sculpture on the distal quarter. Petiole smooth and shining ventrally, with areolate sculpture on all other surfaces. Dorsal and lateral surfaces of petiolar node shining through very weak sculpture. A very weak carina present on the petiolar node laterally, extending from the petiolar spiracle to the caudal cylinder. Postpetiole smooth and shining, with weak areolate sculpture on the posterior quarter. Gaster smooth and shining, without spectral iridescence.

Setae: antennal scapes and funiculi with short, adpressed pilosity. Dorsum of head, pronotum, waist segments, and gaster with moderately abundant, erect, blunt-tipped setae, the longest of which are about the width of the compound eye. The head bears ~30, mesosoma ~20, petiole 4, postpetiole ~12, and first gastral tergite ~32 setae. Short, sparse pubescence present over the entire body, but difficult to detect against the lightly colored integument.

Color: predominantly yellow, with the head capsule (excluding clypeus) and posterior third of the first gastral tergite dark brown.

Gyne measurements & indices (n = 2): SL = 0.491 –0.498 (0.495); FRS = 0.244 –0.253 (0.249); CW = 0.681 –0.691 (0.686); CWb = 0.639 –0.649 (0.644); PoOC = 0.259 –0.268 (0.264); CL = 0.661 –0.692 (0.677); EL = 0.184 –0.191 (0.188); EW = 0.153 –0.162 (0.158); MD = 0.137 –0.139 (0.138); WL = 1.066 –1.080 (1.073); SPST = 0.253 –0.278 (0.266); MPST = 0.270 –0.290 (0.280); PEL = 0.365 –0.380 (0.373); NOL = 0.18; NOH = 0.135 –0.144 (0.140); PEH = 0.262 –0.263 (0.263); PPL = 0.187 –0.199 (0.193); PPH = 0.282 –0.302 (0.292); PW = 0.646 –0.653 (0.650); SBPA = 0.311 –0.314 (0.313); SPTI = 0.295 –0.303 (0.299); PEW = 0.176 –0.184 (0.180); PNW = 0.201 –0.204 (0.203); PPW = 0.470 –0.477 (0.474); HFL = 0.566 –0.589 (0.578); HFWmax = 0.124 –0.135 (0.130); HFWmin = 0.051 –0.054 (0.053); CS = 0.980 –0.985 (0.982); ES = 0.261 –0.272 (0.266); SI = 77; OI = 27–28 (27); CI = 92–98 (95); WLI = 166–167 (167); SBI = 48–49 (49); PSI = 24–26 (25); PWI = 259–267 (263); PLI = 191–195 (193); NI = 125–133 (129); PNWI = 109–116 (113); NLI = 47–49 (48); FI = 243–250 (247).

Gyne description: In full-face view, head subquadrate, about as long as broad (CI 92–98). Mandibles weakly striate, shining, and armed with five teeth: the apical-most well developed, followed by a less developed preapical tooth and three equally-developed smaller teeth. Anterior clypeal margin weakly convex medially. Antennal scapes moderately long: when fully retracted, just reaching the posterior margin of the head capsule (SI 77). Antennae 12-segmented; antennal club of three segments, with the apical-most segment as slightly longer than the preceding two in combination. Frontal carinae moderately long, extending past the antennal toruli by about four times the maximum width of the antennal scape. Compound eyes protruding past the lateral margins of the head capsule. Lateral margin of head evenly convex, converging from below the compound eyes to the mandibular insertions. Posterior head margin weakly convex, rounding evenly into the lateral margins.

In profile view, compound eyes ovular and large (OI 27–28), with 16 ommatidia in longest row. Mesoscutum rounded evenly anteriorly, covering the dorsal surface of the pronotum, and flat dorsally; mesoscutellum on the same level as the mesoscutum, not overhanging the metanotum. Propodeal spiracle well developed, directed posterolaterally, and separated from the propodeal declivity by about spiracle diameters. Propodeal spines stout and well developed, but short (PSI 24–26), about two thirds as long as the propodeal declivity, tapering evenly from the base, straight, and directed posteriorly. Propodeal declivity weakly concave, forming a rounded ~90 ° angle with the base of the propodeal spines. Propodeal lobes rounded and weakly developed. Metapleural gland bulla small, extending from the metacoxal insertion halfway to the propodeal spiracle. Petiole long (PLI 191–195), without tubercles anterodorsally where it articulates with the mesosoma; subpetiolar process in the form of a moderately well developed, acute, triangular tooth, which grades evenly into the ventral margin of the petiole posteriorly. Petiolar peduncle short: comprising about one third of the total length of the petiole. Petiolar node erect: transition between peduncle and node evenly rounded, resulting in a very slightly concave anterior node face; anterior face forming a sharp ~90 ° angle with the dorsal face, which is short and evenly rounds into the posterior face, which forms a ~110 ° angle with the caudal cylinder. Postpetiole evenly rounded anterodorsally, bulging slightly before it transitions into the flattened dorsal face; ventral surface weakly lobed.

In dorsal view, mesoscutum covering pronotum anteriorly, but humeri visible laterally as rounded sclerites. Propodeal spines weakly diverging apically, their apices separated from each other by about one and a half times their length. Petiolar peduncle with spiracles not protruding past the lateral margins. Petiolar node widest anteriorly, and emarginated anterodorsally; lateral faces converge to the indistinct posterior face. Petiolar node slightly broader than the peduncle, and evenly grading into the caudal cylinder, which slightly narrower than the node. Postpetiole very broad (PWI 259–267), anteroposteriorly compressed, and campaniform, articulating with most of the anterior margin of the gaster, leaving small, angulate margins on each side exposed. Anterior margin of the postpetiole weakly concave, evenly rounded as it transitions to the lateral margins, which evenly diverge to the angulate posterior corners; posterior margin broadly concave. Metafemur weakly incrassate (FI 243–250).

Sculpture: median clypeal carina present, extending from the anterior margin nearly to frontal triangle, and flanked by weaker, indistinct carinae; lateral margins of median clypeal lobe with two carinae that are as strong as the medial carina. Lateral clypeal lobes with additional weaker carinae; ground sculpture smooth and shining. Antennal scapes shining through weak areolate sculpture. Cephalic dorsum with costulae, which become weaker posteriorly; a strip of smooth sculpture present medially, surrounding a central carina, which extends from the frontal triangle nearly to the median ocellus; weak concentric costulae surrounding the antennal insertions. Lateral surfaces of head with weak areolate sculpture posterior to the compound eye, dense rugose sculpture surrounding the compound eye, with costulae superimposed over this sculpture. Ventral surface of head shining, with weak rugae. Pronotal neck areolate. Pronotum with weak areolate ground sculpture arranged into longitudinal rows and separated by superficial costulae. Anepisternum and katepisternum shining on their anterior halves, transitioning into weak costulae posteriorly. Propodeum with stronger costulae laterally; propodeal declivity weakly areolate. Mesoscutum with costulae over weak areolate ground sculpture surrounding a smooth and shining central strip which extends over half of the sclerite from the anterior margin; mesoscutum also with smooth and shining patches laterally. Mesoscutellum smooth and shining medially, surrounded by weak costulae and areolae. Femora smooth and shining, with traces of weak areolate sculpture distally. Petiole with weak areolate sculpture laterally, and on the dorsoposterior surface of the node; dorsal surface of the peduncle and the anterior face of the node shining through weak sculpture. Postpetiole smooth and shining anteriorly, areolate laterally and on the posterior half. Gaster smooth and shining, without spectral iridescence. Surface of the first gastral sternite smooth and shining.

Setae: antennal scapes and funiculi with short, adpressed pilosity. Dorsum of head, pronotum, waist segments, and gaster with moderately abundant, erect, blunt-tipped setae, the longest of which are about a third of the width of the compound eye. Short, sparse pubescence present over the entire body, but difficult to detect against the lightly colored integument.

Color: predominantly yellow, with the head capsule (excluding clypeus), anepisternum, median of the mesoscutellum, and posterior halves of the gastral tergite dark brown.

Male: Unknown.

Etymology: From the headgear used by British troops during the Battle of Balaclava during the Crimean war, in reference to the distinctive coloration of the cephalic integument.

Comments: Temnothorax balaclava sp. nov. is known only from low elevation xerophytic forest in Jaragua National Park in southwestern Dominican Republic, where partial nests were collected from partially buried wood, leaf litter, and soil. Other details of the biology of this species are unknown but are probably similar to other members of the terricolous pan-Caribbean pulchellus group. This taxon is part of a species complex with T. bahoruco sp. nov., T. ciferrii , and T. wilsoni sp. nov., all of which have only been collected from allopatric populations in mountains and low-lying dry forest from the southern parts of Hispaniola. The worker is morphologically quite similar to T. bahoruco sp. nov. and T. wilsoni sp. nov., differing primarily in the conformation of the clypeus, coloration, and sculptural details.

Figures

Figure 133 Geographical and elevational distribution of the pulchellus group. (A) Temnothorax agavicola sp. nov. (B) T. albispinus. (C) T. bahoruco sp. nov. (D) T. balaclava sp. nov. (E) T. ciferrii (F) T. flavidulus (G) T. harlequina sp. nov. (H) T. hippolytus sp. nov. (I) T. laticrus sp. nov. (J) T. magnabulla sp. nov. (K) T. pulchellus (L) T. terricola (M) T. torrei (N) T. wettereri sp. nov. (O) T. wilsoni sp. nov. Colored scale to the left of each map represents elevation in meters. Points in black represent the species named in each subfigure, while points in red represent other members of the species group. Type localities are represented by triangles; if present, types of synonyms are named; non-type localities are represented by circles. Bounding box in inset map shows location of main map. Full-size DOI: 10.7717/peerj.11514/fig-133

Figure 138 Temnothorax balaclava sp. nov. (A–C) Holotype worker (CASENT0758262). (A) Full-face view. (B) Profile view. (C) Dorsal view. (D–F) Paratype gyne (MCZENT00510550). Scale bars 0.2 mm. Full-size DOI: 10.7717/peerj.11514/fig-138