Temnothorax proteii

Workers of this species were found in material collected on an entomological umbrella. Habitats where it has been collected include blackberry bushes growing along roads, deciduous forests and macchia and bushes overgrowing banks of streams or rivers. Nests have never been found but are probably in dry branches or galls.

Identification
Salata et al. (2018) – One of a number of species characterized by a lack of metanotal groove, an uneven reddish brown to orange body colouration, the presence of propodeal spines, and longitudinal striation on the head. On Crete it can only be confused with Temnothorax crassistriatus, with  T. proteii differing in the presence of reticulation between striae on the head and mesosoma, a higher petiole node with a flat dorsal surface, and the absence of striae on the petiole and postpetiole. Beyond Crete T. proteii has characters similar to: Temnothorax affinis, but differs in the lack of longitudinal reticulation on the frons, its thicker body striation, and a lack of microstriation between rugosities; Temnothorax graecus, but differs in the flat dorsal surface of the propodeum and longer propodeal spines; Temnothorax clypeatus, but differs in lacking a medial notch on the anterior margin of the clypeus; Temnothorax corticalis, but differs by its well-developed petiole peduncle and the flat dorsal surface of the petiole.

Temnothorax proteii is the most morphologically differentiated Cretan Temnothorax. The species description, of the holotype, represents the most common morphology. Other specimens exhibit variation in the following characters:


 * Color: body colouration brighter, reaching up to bright orange or yellow; size and color of dark stain covering head, varying from brown and showing only on the posterior parts of the malar area and frons to black and covering the entire malar area, frons and vertex.
 * Frons sculpture: longitudinal striation can be sometimes interrupted, especially on the anterior part of frons. Rugosity, which covers the area between striation, can sometimes weaken or disappear on the whole frons centre.
 * Genae sculpture: longitudinal striation can be absent.
 * Mesosoma sculpture: its dorsal surface can sometimes be covered by thick, sparse to moderately dense longitudinal striae, which may be interrupted, and the area between striae is always rugulose. Longitudinal striation can co-occur or be replaced by longitudinal reticulation or irregular reticulation. Lateral surfaces can have longitudinal striation limited to the pronotum.
 * Petiole sculpture: some specimens have, except rugosity, few wrinkles on its surface. Propodeal spines: some specimens have propodeal spines short and triangular, in other the tips can be straight.

Workers are characterized by wide differentiation in body length, head and mesosoma sculpture, and the shape and length of propodeal spines. Small workers have denser, gentler body sculpture and shorter propodeal spines. This worker type is similar to species from the T. graecus group. Larger workers have sparse, thick body sculpture and well-developed propodeal spines, like species from the T. affinis group.

Ecological evidence suggests this is a single species, despite the morphological variation. Small and large workers were almost always collected from the same plant or bush, as were individuals with intermediate features. Other Greek Temnothorax species that establish nests inside stems of plants also exhibit wide morphological variation. Because we failed to collect the nest sample of such a common species, we suspect that T. proteii also has nests inside plant stems.

Distribution based on Regional Taxon Lists
Palaearctic Region: Greece.

Biology
This species is the most abundant Temnothorax species on Crete.

Nomenclature

 *  proteii. Temnothorax proteii Salata, Borowiec & Trichas, 2018: 788, figs. 56-60 (w.) GREECE (Crete).

Worker
(n=15): HL: 0.703 ± 0.02 (0.653-0.748); HW: 0.586 ± 0.02 (0.559-0.614); SL: 0.5 ± 0.02 (0.463-0.542); EL: 0.159 ± 0.006 (0.148-0.168); EW: 0.122 ± 0.006 (0.112-0.134); ML: 0.801 ± 0.03 (0.754- 0.872); PSL: 0.194 ± 0.01 (0.17-0.218); SDL: 0.13 ± 0.009 (0.114-0.145); PL: 0.325 ± 0.02 (0.296-0.363); PPL: 0.202 ± 0.01 (0.184-0.223); PH: 0.22 ± 0.009 (0.207- 0.24); PPH: 0.217 ± 0.01 (0.201-0.251); HTL: 0.479 ± 0.04 (0.38-0.525); PNW: 0.406 ± 0.02 (0.38-0.447); PW: 0.181 ± 0.01 (0.168-0.201); PPW: 0.239 ± 0.01 (0.218- 0.265); HI: 83.2 ± 1.9 (80.6-86.6); SI1: 71.2 ± 1.5 (68.0- 74.3); SI2: 85.7 ± 2.0 (81.8-90.0); MI: 59.7 ± 3.8 (47.9- 63.4); EI1: 76.5 ± 3.2 (71.4-81.1); EI2: 17.2 ± 1.1 (15.3- 18.9); TI: 122.7 ± 9.8 (116.3-151.5); PI: 147.8 ± 5.6 (138.5-159.5); PPI: 91.8 ± 4.8 (82.5-97.4).

Head and mesosoma rusty brown. Vertex centre, posterior parts of frons and malar area brown to black. Flagellum, legs and base of the first tergite of gaster brown to bright brown. Tibiae with darker central part.

Head oval, 1.2 times as long as wide, lateral surfaces below and above eyes slightly convex, posterior edges convex, occipital margin of head straight. Anterior margin of the clypeus slightly convex, without median notch. Eyes small, oval, 1.3 times as long as wide. Antennal scape short, in lateral view slightly curved, 0.7 times as long as length of the head, in apex gradually widened, its base with small, triangular tooth, funiculus long, club 3 segmented. Surface of scape with very fine microreticulation, shiny, covered with thin, dense, adpressed to subdecumbent setae. Mandibles rounded with thick sparse, longitudinal striae, shiny. Clypeus shiny, with a few, thick, longitudinal striae, area between striae smooth and shiny. Frontal carinae short, not extending beyond frontal lobes. Antennal fossa deep, with a few roundly curved striae, area between striae shiny, with sparse and slight reticulation. Frontal lobes narrow, smooth and shiny. Frons shiny, with thick, dense longitudinal striation, area between striae, on center and anterior part, with rugosity, posterior part with smooth area. Gena, area between eyes and frontal carina and occipital part of head shiny, with thick reticulation and a few longitudinal, thin striae, area between sculpture microreticulate. Whole head surface bearing suberect to erect, pale, short and thick setae.

Mesosoma elongate, 2.0 times as long as wide, slightly arched in profile. Pronotum rounded on sides. Propodeal spines medium length, narrow, with wide base, posterior part directed upward, tips slightly curved downward, sharp. Dorsal surface of mesosoma shiny, with dense, thick, longitudinal reticulation, area between sculpture with sparse microreticulation. Lateral surfaces of mesosoma with thick, sparse longitudinal striation, area between striae with dense reticulation. Entire mesosoma bearing suberect to erect, pale, short and thick setae.

Petiole, in lateral view, with medium-length peduncle, node high, with anterior face straight, posterior face convex, its dorsal surface flat, inclined posteroventral. Postpetiole, in lateral view, regularly convex, apical half with gently convex sides. Peduncle, petiolar node and postpetiole dorsum shiny, with thick, dense reticulation, area between rugae smooth.

Gaster smooth and shiny, bearing erect, thin, pale setae. Legs short, shiny, with fine micro - reticulation. Tibiae 0.7 times as long as head length, bearing adpressed to documbent setae on the whole surface. Inner margins of tibia without a row of erect setae.

Type Material
Holotype (w.) (CASENT0845924): Collection L. Borowiec, Formicidae, DBET-GR00565 ; GREECE W Crete 10-15 m, Kato Daratso n. Chania, 35°30 ’N/23°59’E litoral, 6 V 2011. L. Borowiec ; Paratypes (11w.) (CASENT 0845925-CASENT0845935): the same data as holotype, and.

Etymology
Named after Greek sea-god Proteus /Πρωτεύς/ who was known for his ability to change his shape. Specimens of Temnothorax proteii vary in head sculpture and propodeal spines length and shape what makes it the most morphologically differentiated species known from Crete.

References based on Global Ant Biodiversity Informatics

 * Salata S., L. Borowiec, and A.Trichas. 2018. Taxonomic Revision of the Cretan Fauna of the Genus Temnothorax Mayr, 1861 (Hymenoptera: Formicidae), with Notes on the Endemism of Ant Fauna of Crete. Annales Zoologici (Warsaw) 68(4): 769-808.
 * Salata S., and L. Borowiec. 2018. Taxonomic and faunistic notes on Greek ants (Hymenoptera: Formicidae). Annals of the Upper Silesian Museum in Bytom Entomology 27: 1-51.