Protalaridris arhuaca

All specimens of P. arhuaca have been collected from sifted leaf-litter in premontane rain forest between 1180 and 1650 m on the northwestern slopes of the Sierra Nevada de Santa Marta. The holotype and specimen CASENT0644163 were found in the lower site, a dense forest with closed canopy and abundant leaf-litter. Specimens CASENT0644170 & CASENT0644171 were taken from secondary growth forest with an open canopy and some scattered large trees. The site is surrounded by pastures and crossed by trails. The litter in this site was taken from the base of the largest trees.

Identification
Lattke et al. (2018) - Cephalic vertex with median subquadrate elevation. Labrum wider than long, deeply cleft with 8 large anterolateral hairs and no hairs in labral cleft. Overlapping preapical mandibular teeth between midlength of mandible and base of apical tooth belong to dorsal row. Frontovertexal ridge with abundant small protuberances. Dorsum of head, most of mesosoma, petiolarnode, and postpetiole torose-rugulose.

Protalaridris arhuaca is similar to Protalaridris loxanensis, also having a large apical tooth that overlaps its counterpart on the opposing mandible. In Protalaridris arhuaca this tooth is part of the dorsal row of dentition, in contrast with Protalaridris loxanensis where the tooth is part of the ventral row of preapical mandibular dentition. Their respective head lengths and labral configuration also permit separation. The head length of Protalaridris arhuaca is the longest in Protalaridris, including Protalaridris loxanensis (HL > 0.80 mm vs. 0.76–0.78 mm, respectively). Protalaridris arhuaca has a subquadrate head compared with the subrectangular shape in Protalaridris loxanensis (CI ≤ 1.07 vs. ≥ 1.10). Although other Protalaridris may have quadrate to subquadrate heads, their respective widths and lengths are less than in Protalaridris arhuaca In a dorsal cephalic view the mandibles, when closed, cover the lateral margins of the labrum in Protalaridris arhuaca, but in Protalaridris loxanensis these margins are visible despite full mandibular closure. The labrum in Protalaridris loxanensis has a weak anterior concavity but in Protalaridris arhuaca the labrum is deeply cleft. Protalaridris punctata also has a relatively wide labrum with a deep emargination, as in Protalaridris arhuaca, but this cleft forms an acute angle in Protalaridris punctata and in Protalaridris arhuaca it forms an obtuse angle.

Distribution
Only known from the Sierra Nevada of Santa Marta, Magdalena, Colombia.

Distribution based on Regional Taxon Lists
Neotropical Region: Colombia.

Nomenclature

 *  arhuaca. Protalaridris arhuaca Guerrero, Lattke & Alpert, in Lattke et al., 2018: 274, figs. 3a-d (w.) COLOMBIA.

Worker
Holotype (paratypes, n = 3): HL 0.84 (0.82–0.87); HW 0.87 (0.86–0.90); ML 0.53 (0.53–0.57); EL 0.04 (0.05–0.06); SL 0.49 (0.47–0.51); PW 0.49 (0.48–0.52); WL 0.72 (0.73–0.79); PH 0.20 (0.20–0.22); PL 0.37 (0.36–0.43); PPL 0.20 (0.19–0.24); PPW 0.38 (0.34–0.39); DPW 0.26 (0.25–0.27) mm. CI 1.04 (1.05–1.07); MI 0.61 (0.60–0.63); OI 0.04 (0.06–0.07); SI 0.56 (0.54–0.56); LPI 0.54 (0.51–0.58); DPI 70 (63–72).

Head slightly wider than long in full-face view; posterior margin broadly concave to straight with small median emargination; lateral cephalic margin posterior to antennal fossa forming blunt obtuse angle with straight to weakly convex sides, widest at frontovertexal ridge, lateral margin forms discrete angle with posterior margin of antennal fossa; lateral cephalic margin briefly concave along posterior half of antennal fossa, then gradually curves convex towards clypeus. Anterior clypeal margin medially concave with lateral convex lobe next to basal mandibular flange. Cephalic lateral margin bordered by raised, blunt carina that curves medially to form strongly raised frontovertexal ridge shaped as broad, anteriorly facing concavity, continuously arching except for brief median concavity that forms anterior margin of median vertexal protuberance. Antennal fossa conspicuous, as long as wide, reaching barely half the length of the head, anterior margin straight, internal margin sinuous; anterior margin of fossa brief and transverse, frontal carina with anterior half convex and posterior half shaped as subquadrate to convex emargination. Internal surface of the fossa densely foveolate, without pilosity. Cephalic dorsal surface irregularly rugulose from frontovertexal ridge to anterior clypeal margin; head posterad of ridge with abundant rounded, protuberances connected by short and thick sharply-crested rugulae, sculpture more accentuated posterolaterally; bunched series of longitudinal rugulae extend posteriorly from frontal carina forming low, broad crest that almost touches frontovertexal ridge. Ill-defined longitudinal median ridge present, extending posterad from posterior clypeal margin. Area between longitudinal and lateral carinae strongly concave, area posterad to frontovertexal ridge with median, subquadrate-shaped raised area (best seen in dorsal view of the posterior cephalic margin) laterally bound by ovoid depression. Cephalic dorsum with short and apically acute, appressed hairs, each hair separated by distance equal to or greater than its length. Mandible elongate, external and internal margins in full-length view mostly parallel, cross-section at one-third anterior-length is convex externally and straight (vertical) internally; mandible tapers to medially directed, acutely pointed apical tooth, as long as 1/3 mandibular length.

Mandibular internal margin with longitudinal dorsal row of 4 teeth and 3–4 denticles: teeth situated apicad of massive ventral tooth, from the base apicad, teeth 1–3 relatively small and non-overlapping; tooth 4 large, approximately twice as long and as wide at base than preceding teeth. Tooth 4 situated anterad of mandibular mid-length and overlapping with large tooth of other mandible, 2–3 denticles situated apicad of tooth, 1 or two denticles situated basad of tooth 1; mandibular internal margin with ventral row of 5–6 denticles best seen ventrally, posteriormost denticle largest in size and situated on base of large ventral tooth. Ventral tooth placed closer to mandibular base than to mid-length, crossing opposing tooth from other mandible, internal ridge with low triangular flange. Mandibular dorsum mostly rugulose-torulose, ventrally mostly smooth and shining, including ventral tooth and apical tooth; mandibular basal flange finely areolate. Mandible with sparse curved decumbent hairs along lateral margin, apex of each hair contacting mandibular surface; ventral mandibular surface with 2 rows of very short erect hairs between base of ventral tooth and base of apical tooth; 6–8 obliquely positioned, long hairs present from mandibular base to basal half of ventral tooth.

Labrum wider than long, anterolaterally bluntly angular and lateral margin convex, anteromedially with narrow V-shaped incision as long or longer than labral mid-length; dorsal surface shining and rugulose with fine punctae; labrum anterolaterally with 4 thick, cylindrical hairs, 2 hairs on anterior margin and 2 hairs on anterolateral margin, lateralmost hair the shortest, no hairs in median emargination, apex of some hairs flattened; ventral surface of labrum with erect pubescence and subspatulate hairs, some apically cleft.

Scape barely reaches frontovertexal ridge; in dorsal view with two oblique surfaces separated by longitudinal carina, internal surface with bead-like projections arranged in rows and low carinae, external surface with two longitudinal concavities separated by median lamella; external margin with 2 rows of hairs, dorsal row with 6 lamellate thick hairs, ventral row of 9–10 cylindrical thick hairs, narrower than dorsal hairs. Scape opaque, funiculus shining. Antenna with pedicel as wide as long, campaniform; segment 3 trapezoid, slightly wider than long, segments 4–8 trapezoid, serially increasing in length, 2–8 punctulate, apical segment smooth; scape apex with semierect hairs, following segments with abundant decumbent to subdecumbent hairs as long as pedicel. Eye reduced to single ommatidium, separated from dorsal cephalic surface by distance equal to less than one diameter.

Dorsal margin of mesosoma in lateral view mostly convex, dorsal propodeal margin concave to apex of tooth; pronotal collar opaque and finely punctate; propleuron finely areolate. Mesometapleuron briefly cleft along ventral margin, mesopleuron mostly flat, rugulose ventrally; metapleuron mostly flat except for anterodorsal depression next to propodeum, depression and propodeum joined by carina; mesopleuron posteroventrally convex. Spiracle rounded, posteriorly facing; dorsal propodeal face separated from declivity by transverse carina. Mesosoma trapezoid in dorsal view, widest anterad, most of mesosomal dorsum and lateral surfaces of pronotum and mesonotum torose-rugulose. Propodeal declivity finely areolate; narrow posteroventral strip of pronotum, mesometapleuron, and lateral propodeal face pruinose with shallow foveolae. Anteroventral margin of pronotum with shallow, roughly scrobiculate sulcus. Mesosomal dorsum lacking standing hairs. Petiole as long as propodeal declivity in lateral view, dorsal margin straight, ventral margin slightly sinuous; node discrete, rectangular in dorsal view, wider than long; postpetiole twice as wide as long, anterior margin strongly concave, posterior margin very convex, lateral margins posteriorly diverging. Most of petiole densely foveolate, dorsum of petiolar node and postpetiole torose-rugulose. Fourth abdominal tergite anteriorly concave in dorsal view, complementing posterior convex margin of postpetiolar tergite; fourth abdominal segment makes up 3/4 of gaster, dorsum of tergite foveolate-rugose; sides of fourth abdominal tergite, all gastral sterna, and rest of tergites densely foveolate; gastral dorsum with more than 10 erect, subspatulate hairs; sparse pubescence also present; sternites with sparse erect hairs.

Coxae finely areolate. Femora with anterior, posterior, and ventral surfaces relatively flat, dorsally convex; erect and semierect hairs present on both internal and external femoral surfaces; tibiae laterally compressed, dorsal margin in lateral view straight and ventral margin convex; mesoand metatibia longer than protibia. First tarsomere of each leg half as long as respective tibia, tarsomeres 2–4 each slightly longer than wide. Coxae and lateral tibial surfaces densely foveolate; dorsum and apical-lateral surface of profemur mostly torulose-rugulose, meso- and metafemora apically torulose-rugulose, basally foveolate. Tibiae with thick flattened hairs on ventral surface, hairs as long as half tibial width. Lateral apex of tibiae each with flattened spatulate hair, mesotibial apex with small flattened hairs on posterior side. Head, scape, mandible, promesonotum and most of dorsal propodeal face and rest of abdomen brown; funiculus, mesometapleuron, lateral and declivitous propodeal faces, and most of legs yellowish-brown; mandibular apical tooth reddish-brown.

Type Material
Holotype worker (point-mounted; ICN): COLOMBIA. Magdalena: 9 km SE Minca, 11.08972° –74.06021° ±100 m, 1650 m, 28 May 2017, R. Guerrero, J. Longino#9848- s. Taken in secondary growth montane wet forest from sifted leaf litter. Holotype bears red label with unique specimen identifier ‘ICN 093589’. Paratypes: Three point-mounted workers with same data as holotype: One with unique specimen identifier CASENT0644163 and a Q code, deposited in. One with unique specimen identifier CASENT0644170 and a Q code, deposited in. One with unique specimen identifier CASENT0644171 and a Q code, deposited in JTLC.

Etymology
The species epithet is in recognition of the Arhuaco people, an indigenous group with ancestral lands close to the type locality of the species.