Temnothorax longinoi

Nests and forages arboreally.

Identification
Prebus (2021) – A member of the salvini group of the Temnothorax salvini clade. Temnothorax longinoi can be separated from all other species in the salvini clade by the following character combination: dorsum of mesosoma flat; metanotal groove not impressed; propodeum not strongly depressed below the level of the promesonotum; propodeal spines straight and about as long as the propodeal declivity; subpetiolar tooth small long and acute: longer than the setae that arise from the peduncle directly above; petiolar node weakly squamiform: in dorsal view, petiolar node less than or equal to 1.6 times as broad as caudal cylinder; setae on head, mesosoma, legs, waist segments and gaster erect to suberect, long, abundant and tapering; integument uniformly dark brown to weakly bicolored; bicolored form with clypeus, mandibles, mesosoma, and waist segments testaceous brown.

Similar species: Fellow members of the salvini group. Temnothorax longinoi can be separated from other members of the salvini group by the weakly squamiform petiolar node (petiolar node more than or equal to 1.6 times as broad as the caudal cylinder in Temnothorax aztecus, Temnothorax aztecoides, Temnothorax longicaulis and Temnothorax paraztecus), relatively large subpetiolar tooth (shorter than the setae that arises from the dorsum of the petiolar peduncle directly above it in Temnothorax quetzal, Temnothorax fortispinosus, Temnothorax parvidentatus, and Temnothorax salvini), and short propodeal spines (as long as or longer than the propodeal declivity in Temnothorax quetzal, T. aztecoides, and T. aztecus).

This species is morphologically uniform across its range, but a weakly bicolored form is known from Honduras.

Distribution
Mid-to-high elevations, Guatemala to Nicaragua.

Distribution based on Regional Taxon Lists
Neotropical Region: Guatemala, Honduras, Nicaragua.

Biology
Prebus (2021) - Temnothorax longinoi is common in mid-to-high elevation cloud forests of Mesoamerica between the Isthmus of Tehuantepec and the Nicaraguan depression. Like many of its close relatives in the salvini species group, it nests in hollow stems and forages arboreally. Temnothorax longinoi is morphologically similar to Temnothorax longicaulis and Temnothorax salvini. Together, these species are the sister group to T. longinoi, having shared a common ancestor with it around 8 Ma before dispersing to the southern Central American cordilleras during the Miocene-Pliocene transition (Prebus, 2020).

Nomenclature

 * . Temnothorax longinoi Prebus, 2021: 387, figs. 153E, 158, 159 (w.aq.m.) NICARAGUA.

Worker
(n = 18): SL = 0.738-0.869 (0.814); FRS = 0.247-0.292 (0.270); CW = 0.795-0.933 (0.876); CWb = 0.703-0.834 (0.783); PoOC = 0.310-0.358 (0.333); CL = 0.782-0.927 (0.874); EL = 0.189-0.244 (0.228); EW = 0.142-0.169 (0.158); MD = 0.178-0.249 (0.204); WL = 1.012-1.281 (1.164); SPST = 0.267-0.355 (0.325); MPST = 0.293-0.359 (0.332); PEL = 0.359-0.477 (0.433); NOL = 0.217-0.291 (0.260); NOH = 0.118-0.188 (0.159); PEH = 0.230-0.309 (0.272); PPL = 0.185-0.252 (0.224); PPH = 0.223-0.307 (0.275); PW = 0.469-0.606 (0.549); SBPA = 0.180-0.264 (0.230); SPTI = 0.216-0.306 (0.268); PEW = 0.145-0.193 (0.177); PNW = 0.208-0.301 (0.262); PPW = 0.234-0.330 (0.288); HFL = 0.808-0.999 (0.930); HFWmax = 0.160-0.217 (0.185); HFWmin = 0.050-0.071 (0.063); CS = 1.103-1.298 (1.220); ES = 0.262-0.321 (0.307); SI = 99-109 (104); OI = 24-27 (25); CI = 84-94 (90); WLI = 142-157 (149); SBI = 25-33 (29); PSI = 26-31 (28); PWI = 152-176 (163); PLI = 166-216 (194); NI = 139-198 (165); PNWI = 141-161 (148); NLI = 53-64 (60); FI = 262-326 (294).

In full-face view, head subquadrate, longer than broad (CI 84-94). Antennal scapes very long: when fully retracted, surpassing the posterior margin of the head capsule by about three times the maximum width of the antennal scape (SI 99-109). Antennae 12-segmented; antennal club of composed of three segments, with the apical-most segment about as long as the preceding two in combination. Frontal carinae short: extending past the antennal toruli by about one and a half 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 mandibular insertions to the posterior margin of the head. Posterior head margin weakly concave medially but rounding evenly into the lateral margins.

In profile view, compound eyes ovular and moderately large (OI 24-27), with 14 ommatidia in longest row. Pronotal declivity indistinct, neck and anterior face of pronotum forming a ~110° angle. Mesosoma very weakly sinuate: promesonotum weakly convex from where it joins the pronotal neck to the weakly impressed mesometanotal sulcus; metanotum weakly convex; propodeum slightly depressed below the mesonotum, and flat to the base of the propodeal spines. Promesonotal suture extending from the posterior margin of the procoxal insertion to the mesothoracic spiracle, which is well developed, then continuing dorsally as a weak sulcus. Metanotal groove visible as a disruption of the sculpture laterally from where it arises between the mid- and hind coxae to the poorly developed metathoracic spiracle, which is nearly indistinguishable against the ground sculpture; continuing dorsally as a faint impression to the anterior margin of the metanotum. Propodeal spiracle well developed, directed posterolaterally, and separated from the propodeal declivity by about four spiracle diameters. Propodeal spines moderately well developed and moderately long (PSI 26-31), about as long as the propodeal declivity, flared at the base, straight, and acute. Propodeal declivity flat, forming a rounded ~120° angle with the base of the propodeal spines. Propodeal lobes rounded and weakly developed. Metapleural gland bulla moderately large, extending from the metacoxal insertion two thirds of the way to the propodeal spiracle. Petiole moderately long (PLI 166-216), without tubercles anterodorsally. Subpetiolar process in the form of a moderately long, anteriorly curved, acute spiniform tooth; ventral margin of petiole weakly bulging posterior to it. Petiolar peduncle moderately long: comprising about half of the total length of the petiole. Petiolar node erect and rounded dorsally: transition between peduncle and node marked by a rounded angle of ~140°, resulting in a weakly concave anterior node face; anterior face rounding evenly into the dorsal face, which is evenly convex; dorsal face rounding evenly into the posterior face, which forms a ~100° angle with the caudal cylinder. Postpetiole evenly rounded anterodorsally, bulging before flattening posterodorsally; concave ventrally.

In dorsal view, humeri developed and distinct: evenly rounded and 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. Promesonotal suture visible as a faint sulcus and disruption in the ground sculpture. Metanotum delineated anteriorly and posteriorly by weak sulci and disruption in the ground sculpture. Propodeal spines narrowly approximated basally and diverging apically, their apices separated from each other by about their length, the negative space between them "U" shaped. Petiolar peduncle with spiracles protruding past the lateral margins, but not noticeably constricted anterior to them. Petiolar node, when viewed posterodorsally, rounded-trapezoidal and weakly squamiform: about one and a half times as broad apically as the base; node broader than the peduncle and the caudal cylinder. Postpetiole narrow (PWI 152-176) and subquadrate. Anterior margin of the postpetiole flat but evenly rounding into the lateral margins; lateral margins parallel to each other; posterior corners angulate; posterior margin flat. Metafemur moderately to strongly incrassate (FI 262-326).

Sculpture: median clypeal carina present but indistinct, extending posteriorly nearly to the frontal triangle, and flanked on either side by three indistinct carinae. Lateral clypeal lobes with additional, weaker carinae; ground sculpture weakly areolate. Antennal scapes finely areolate. Cephalic dorsum finely areolate, with predominantly rugose-costate sculpture overlying the ground sculpture; concentric costulae surrounding the base of the antennal insertions. Lateral surfaces of head sculptured similarly to the dorsum. Ventral surface of head shining, with shallow areolae, and weak costulae. Pronotal neck areolate. Lateral face of pronotum weakly areolate, with coarse costae. Lateral face of pronotum, meso- and metapleuron coarsely rugose over areolate sculpture. Propodeal declivity weakly areolate, with strigulae. Dorsal surface of mesosoma weakly areolate, with costate sculpture overlying the ground sculpture, becoming rugose on the pronotum and propodeum. Femora shallowly areolate. Dorsum of the petiolar peduncle, anterior, dorsal and posterior faces of the petiolar node, and base of the lateral face of the node weakly areolate; otherwise shining. Postpetiole with lateral faces and posterodorsal quarter shallowly areolate; otherwise shining. First gastral tergite and sternite smooth and shining, with weak spectral iridescence.

Setae: antennal scapes and funiculi with moderately long, subdecumbent pilosity. Dorsum of the head, pronotum, waist segments, and gaster with abundant, suberect, tapering, flexuous setae, the longest of which are slightly longer than the length of the compound eye and are directed toward the midline of the body. The head bears >80, mesosoma ~80, petiole 22, postpetiole ~30, and first gastral tergite >80 setae. Pubescence present over the entire body, which is nearly as long as the setae.

Color: head and mesosoma predominantly testaceous brown. Dorsum of head, postpetiole and first gastral sclerites dark brown. Mandibles, tarsi, basal two thirds of remaining gastral sclerites, and sting testaceous yellow.

Queen
(n = 2): SL = 0.770-0.819 (0.795); FRS = 0.291-0.298 (0.295); CW = 0.974-1.001 (0.988); CWb = 0.873-0.879 (0.876); PoOC = 0.326-0.348 (0.337); CL = 0.907-0.917 (0.912); EL = 0.271-0.281 (0.276); EW = 0.199-0.205 (0.202); MD = 0.210-0.212 (0.211); WL = 1.646-1.704 (1.675); SPST = 0.343-0.377 (0.360); MPST = 0.424-0.440 (0.432); PEL = 0.541-0.598 (0.570); NOL = 0.304-0.333 (0.319); NOH = 0.204-0.208 (0.206); PEH = 0.353-0.395 (0.374); PPL = 0.281-0.292 (0.287); PPH = 0.417-0.439 (0.428); PW = 0.922-1.006 (0.964); SBPA = 0.430-0.447 (0.439); SPTI = 0.401-0.429 (0.415); PEW = 0.238-0.240 (0.239); PNW = 0.345-0.394 (0.370); PPW = 0.412-0.515 (0.464); HFL = 1.033-1.043 (1.038); HFWmax = 0.181-0.187 (0.184); HFWmin = 0.063-0.077 (0.070); CS = 1.332-1.333 (1.332); ES = 0.371-0.384 (0.377); SI = 88-94 (91); OI = 28-29 (28); CI = 95-97 (96); WLI = 187-195 (191); SBI = 49-51 (50); PSI = 20-23 (22); PWI = 172-216 (194); PLI = 193-205 (199); NI = 149-160 (155); PNWI = 144-166 (155); NLI = 56-56 (56); FI = 243-287 (265).

In full-face view, head subquadrate, slightly longer than broad (CI 95-97). 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 flat medially. Antennal scapes very long: surpassing the posterior margin of the head capsule by about two times the maximum width of the antennal scape (SI 88-94). Antennae 12-segmented; antennal club composed of three segments, with the apical-most segment as long as 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 evenly convex, converging from below the compound eyes to the mandibular insertions. Posterior head margin weakly concave but rounding evenly into the lateral margins.

In profile view, compound eyes ovular and moderately large (OI 28-29), with 20 ommatidia in longest row. Mesoscutum rounded evenly anteriorly, not fully covering the dorsal surface of the pronotum, and flat dorsally. Mesoscutellum on the same plane as the mesoscutum, but rounded posteriorly. Posterior margin of metanotum extending slightly beyond the posterior margin of the mesoscutum. Propodeal spiracle well developed, directed posterolaterally, and separated from the propodeal declivity by about four spiracle diameters. Propodeal spines stout and well developed, but short (PSI 20-23), about as two thirds as long as the propodeal declivity, tapering evenly from the base, directed posteriorly, straight, and acute. Propodeal declivity weakly concave, forming a rounded ~110° angle with the base of the propodeal spines. Propodeal lobes rounded and weakly developed. Metapleural gland bulla moderately large, extending from the metacoxal insertion two thirds of the way to the propodeal spiracle. Petiole moderately long (PLI 193-205), without tubercles anterodorsally. Subpetiolar process in the form of a moderately long, anteriorly curved, acute spiniform tooth; ventral margin of petiole weakly bulging posterior to it. Petiolar peduncle moderately long: comprising about half of the total petiole length. Petiolar node erect and rounded dorsally: transition between peduncle and node marked by a rounded angle of ~140°, resulting in a weakly concave anterior node face; anterior face rounding evenly into the dorsal face, which is evenly convex; dorsal face rounding evenly into the posterior face, which forms a ~100° angle with the caudal cylinder. Postpetiole evenly rounded anterodorsally, bulging before flattening posterodorsally; concave ventrally.

In dorsal view, mesoscutum not fully covering pronotum anteriorly; humeri visible laterally as rounded sclerites. Propodeal spines weakly diverging apically, their apices separated from each other by about twice their length. Petiolar peduncle with spiracles protruding past the lateral margins, but not noticeably constricted anterior to them. Petiolar node, when viewed posterodorsally, rounded-trapezoidal and weakly squamiform: about one and a half times as broad apically as the base; node broader than the peduncle and the caudal cylinder. Postpetiole narrow (PWI 172-216) and subquadrate. Anterior margin of postpetiole nearly flat, with corners evenly rounding into the lateral margins; lateral margins parallel to each other; posterior corners angulate; posterior margin flat. Metafemur weakly to moderately incrassate (FI 243-287).

Sculpture: median clypeal carina present, extending from the anterior margin nearly to frontal triangle, and flanked on either side by three equally strong carinae. Lateral clypeal lobes with additional weaker carinae; ground sculpture weakly areolate. Antennal scapes finely areolate. Cephalic dorsum finely areolate, with rugose-costate sculpture overlying the ground sculpture; antennal insertions surrounded by concentric costulae. Lateral surfaces of head sculptured similarly to the dorsum; rugae becoming stronger between the compound eye and mandibular insertion. Ventral surface of head with weak areolae and weak costulae. Pronotal neck areolate-strigulate. Pronotum weakly areolate anteriorly and costate laterally. Anterior half of anepisternum weakly areolate, with fine costulae on the posterior half. Katepisternum coarsely rugose. Metapleuron and lateral face of propodeum with coarse costae. Propodeal declivity weakly areolate, with fine costulae. Mesoscutum with costae over areolate ground sculpture; a small patch of finely areolate sculpture anteromedially. Mesoscutellum costulate. Metanotum finely areolate. Dorsal face of propodeum coarsely rugose. Femora shallowly areolate. Dorsum of the petiolar peduncle, anterior, dorsal and posterior faces of the petiolar node, and base of the lateral face of the node shallowly areolate; otherwise shining. Postpetiole with lateral faces and posterodorsal quarter shallowly areolate; otherwise shining. First gastral tergite and sternite smooth and shining, with weak spectral iridescence.

Setae: antennal scapes and funiculi with moderately long, subdecumbent pilosity. Dorsum of the head, pronotum, waist segments, and gaster with abundant, suberect, tapering, flexuous setae, the longest of which are slightly longer than the width of the compound eye. Pubescence present over the entire body, which is nearly as long as the setae.

Color: head and mesosoma predominantly testaceous brown. Dorsum of head, postpetiole and first gastral sclerites dark brown. Mandibles, wing bases, and tarsi testaceous yellow.

Male
(n = 2): SL = 0.241-0.248 (0.245); FRS = 0.116-0.143 (0.130); CW = 0.699-0.753 (0.726); CWb = 0.567-0.609 (0.588); PoOC = 0.244-0.255 (0.250); CL = 0.581-0.617 (0.599); EL = 0.267-0.303 (0.285); EW = 0.201-0.218 (0.210); MD = 0.053-0.056 (0.055); WL = 1.156-1.268 (1.212); SPST = n/a; MPST = 0.287-0.318 (0.303); PEL = 0.405-0.428 (0.417); NOL = 0.214-0.249 (0.232); NOH = 0.078-0.103 (0.091); PEH = 0.192-0.222 (0.207); PPL = 0.210-0.226 (0.218); PPH = 0.231-0.240 (0.236); PW = 0.774-0.786 (0.780); SBPA = n/a; SPTI = n/a; PEW = 0.166-0.172 (0.169); PNW = 0.215-0.232 (0.224); PPW = 0.263-0.268 (0.266); HFL = 0.961-1.032 (0.997); HFWmax = 0.109-0.112 (0.111); HFWmin = 0.060-0.066 (0.063); CS = 0.858-0.918 (0.888); ES = 0.368-0.412 (0.390); SI = 41-43 (42); OI = 43-45 (44); CI = 98-99 (98); WLI = 204-208 (206); SBI = n/a; PSI = n/a; PWI = 156-158 (157); PLI = 179-204 (192); NI = 208-319 (263); PNWI = 125-140 (132); NLI = 53-58 (56); FI = 170-182 (176).

In full-face view, head subovate, about as long as broad (CI 98-99). Mandibles shining through very weak striae and armed with five teeth: the apical-most well developed, followed by a smaller preapical tooth and three roughly equally developed smaller teeth. Anterior clypeal margin entire and flat. Antennal scapes short: when fully retracted, failing to reach the posterior margin of the head capsule by about the length of the scape (SI 41-43). Antennae 13-segmented; antennal club composed of four segments, with the apical-most segment slightly shorter than the preceding two in combination. Frontal carinae short, extending past the antennal toruli by about the maximum width of the antennal scape, but continuing on to the median ocellus as weak carinae. Compound eyes strongly protruding past the lateral margins of head capsule. Lateral margin of head convex, margin between the anterior margin of the compound eye and the mandibular insertions converging. Posterior head margin evenly convex, rounding evenly into the lateral margins.

In profile view, compound eyes ovular and large (OI 43-45), with 24 ommatidia in the longest row. Mesoscutum bulging anteriorly, fully covering the dorsal surface of the pronotum, convex dorsally. Mesoscutellum depressed slightly below the level of the mesoscutum, convex dorsally. Posterior margin of mesoscutellum extending beyond the posterior margin of the metanotum. Propodeum strongly depressed, with a declivitous face anteriorly and flat posteriorly; transitioning into the propodeal declivity through a broadly rounded ~95° angle. Propodeal spiracle moderately well developed, directed posterolaterally, and separated from the propodeal declivity by about five spiracle diameters. Propodeal spines absent. Propodeal lobes rounded and weakly developed. Metapleural gland bulla moderately large, extending two thirds of the way between metacoxal insertion and propodeal spiracle. Petiole moderately long (PLI 179-204), without tubercles anterodorsally. Subpetiolar process a minute, acute, triangular tooth; ventral margin of petiole bulging slightly posterior to it. Petiolar peduncle moderately long: comprising about half of the total petiole length. Petiolar node low and rounded dorsally. Postpetiole evenly rounded anterodorsally, bulging slightly before flattening dorsally; concave ventrally.

In dorsal view, mesoscutum fully covering pronotum anteriorly; humeri not visible laterally. Petiolar peduncle with spiracles strongly protruding past the lateral margins. Petiolar node narrower than the peduncle where the spiracles arise, but slightly broader than the caudal cylinder; rounded-trapezoidal when view at a posterodorsal aspect, the apex broader than the base. Postpetiole narrow (PWI 156-158) and campaniform. Anterior margin of postpetiole weakly convex, with the anterior corners evenly rounding into the lateral margins; lateral margins parallel to each other; posterior corners angulate; posterior margin of postpetiole flat. Metafemur not incrassate (FI 170-182).

Sculpture: median clypeal lobe with fine, concentric costulae. Antennal scapes shining through weak areolae. Dorsum of head areolate, with very fine costulae overlying the ground sculpture. Lateral surface of head areolate, with rugulae forming whorls around compound eye. Ventral surface of head shining, with weak areolae and rugulae. Pronotal neck weakly areolate. Anterior face of pronotum shining through weak areolate sculpture. Lateral surface of pronotum predominantly weakly areolate, with weak costulae overlying the ground sculpture. Katepisternum smooth and shining medially, with weak areolate sculpture on the anterior and posterior margins. Anepisternum smooth and shining on the anterior half, posterior half weakly areolate. Metapleuron and lateral face of propodeum densely areolate-rugulose. Propodeal declivity areolate. Dorsally, mesoscutum predominantly shining through weak, indistinct sculpture; Mayrian furrows surrounded by dense, irregular areolate sculpture. Mesoscutellum irregularly areolate costulate. Femora smooth and shining. Petiole predominantly weakly areolate, but dorsum of node shining and indistinctly sculptured. Dorsal surface of postpetiole shining medially, otherwise weakly areolate. First gastral tergite and sternite smooth and shining, without spectral iridescence.

Setae: antennal scapes and funiculi with moderately long, subdecumbent pilosity. Dorsum of the head, pronotum, waist segments, and gaster with abundant, suberect, tapering, flexuous setae, the longest of which are about as long as the width of the compound eye. Pubescence present over the entire body, which is nearly as long as the setae.

Color: head and mesosoma predominantly testaceous brown. Dorsum of head, postpetiole and first gastral sclerites dark brown. Mandibles, antennae, legs, and genitalia testaceous yellow.

Type Material
Holotype worker: NICARAGUA: Nueva Segovia: 14 km NNE Ocotal, ± 20 m, 1,860 m, 24 April 2011, J. Longino #JTL7413, low 2nd growth vegetation, nest in dead stem (CASENT0758892).

Paratype workers, male, and gyne: same data as holotype, 1 worker (CASENT0758893) [CASC] 1 worker (CASENT0619621) 1 male (CASENT0758894) [CASC] 1 male (CASENT0619355)  1 alate gyne (CASENT0619354) [CASC].

Etymology
Patronym, in honor of Jack Longino, who collected the type specimens and whose initiatives were responsible for much of the material used in this study.