Oxyopomyrmex krueperi

Salata and Borowiec (2015) - Forel (1911) and Menozzi (1936) reported finding nests in sandy soil at a barren hill near Thessaloniki and on a path to Pigadia beach at Karpathos. Specimens were also collected in an agricultural field in Iran (Ghahari et al. 2011). Authors found a nest under a stone on the western slope of Psiloritis on Crete, at elevation 578 m a.s.l (above Fourfouras village). The area there is overgrown by a typical Mediterranean shrubland and olive trees.

Identification
Salata and Borowiec (2015) - Worker. Oxyopomyrmex krueperi is clearly distinguished from all other species by a sharply curved border between dorsal and posterior surfaces of the promesonotum (in the profile view). There are only two species, in which the border between dorsal and posterior surfaces of the promesonotum can have such shape: O. emeryi and Oxyopomyrmex nitidior. Oxyopomyrmex krueperi can be easily distinguished from O. emeryi by the thin, longitudinal striae covering the entire frontal surface of its head, the rectangular shape of the head and lacking punctation on the dorsal surface of the pronotum. Oxyopomymex krueperi differs from O. nitidior in the lack of shiny surface on the center of the frons, the gentler and thinner striation on the dorsal and lateral surfaces of the promesonotum and in the black colouration of the body. Among studied material, two workers of O. krueperi had the border between dorsal and posterior surfaces of the promesonotum curved under less acute angle. At first glance, they resemble workers of Oxyopomyrmex laevibus, but O. krueperi differs by having the presence of longitudinal striae at the gena and posterior margin of the head and by having the rugosity covering dorsal surface of the pronotum. Oxyopomyrmex krueperi is distinguished from O. nitidior by lack of smooth and shiny sculpture at the center of the frons and the darker colouration; from Oxyopomyrmex pygmalioni and Oxyopomyrmex polybotesi is distinguished by lacking punctation at the centre of the pronotum and its gena are devoid rugosity; from O. magnus it differs in lacking rugosity at the gena and the SI<100; from O. saulcyi and O. nigripes is distinguished by the convex promesonotum, the weaker striation and rugosity covering the dorsal surface of its promesonotum, the darker colouration and its gena are more shining with weaker and sparser longitudinal striae, never rugulose.

Gyne. Oxyopomyrmex krueperi is distinguished from Oxyopomyrmex magnus by the HI < 100; from Oxyopomyrmex oculatus and Oxyopomyrmex nigripes it differs in lacking rugosity between striation at the gena. It is very hard to distinguish O. krueperi from Oxyopomyrmex saulcyi. Oxyopomyrmex krueperi has a triangular, broadly attached propodeal spines which rising obliquely upwards but the peaks of the spines are posteriorly oriented whereas most of the studied gyne of O. saulcyi has propodeal spines triangular, short, broadly attached, directed obliquely upwards with sharp or blunt peaks. Only one gyne of O. saulcyi had peaks of the propodeal spines directed slightly downward. In distinguishing these two species the differences in the colouration and the geographical separation can be also used (Oxyopomyrmex krueperi has body black with reddish fragments and it occurs in the Eastern part of the Mediterranean region whereas O. saulcyi has body brown to dark brown with paler fragments and inhabits the Western part of the Mediterranean region).

Male. Oxyopomyrmex krueperi is distinguished from O. oculatus by the occurrence of the longitudinal striae on dorsal surface of the scutum and lacking punctation on it; from Oxyopomyrmex insularis it differs in the occurrence of the longitudinal striae at its frons and by having the vertical striation on dorsal surface of the head; from O. nigripes and Oxyopomyrmex emeryi it differs in the occurrence of the rugosity between longitudinal striation at the scutellum; from O. magnus and O. emeryi it can be distinguished by the presence of the lobe-like propodeal spines and from O. saulcyi it differs in the occurrence of smooth, shiny and devoid of the longitudinal striae surface on the dorsal surface of the postpetiole and by the black colouration of the body.

Distribution
Bulgaria; Greece: Crete, Dodecanese, mainland; Iran: East Azerbaijan Province; Macedonia; Turkey.

Distribution based on Regional Taxon Lists
Palaearctic Region: Bulgaria, Greece, Iran, North Macedonia, Turkey.

Biology
Forel (1911) and Menozzi (1936) reported finding nests in sandy soil at a barren hill near Thessaloniki and on a path to Pigadia beach at Karpathos. Specimens were also collected in an agricultural field in Iran (Ghahari et al. 2011). Authors found a nest under a stone on the western slope of Psiloritis on Crete, at elevation 578 m a.s.l (above Fourfouras village). The area there is overgrown by a typical Mediterranean shrubland and olive trees. Other ant species collected at the site were: Aphaenogaster simonellii Emery, A. subterraneoides Emery, Camponotus aethiops (Latreille,), C. jaliensis Dalla Torre, C. kiesenwetteri (Roger), Lepisiota nigra (Dalla Torre), Messor orientalis (Emery), Strongylognathus silvestrii Menozzi, Temnothorax specularis (Emery), and Tetramorium cf. lucidulum.

Nomenclature

 *  krueperi. Oxyopomyrmex krueperi Forel, 1911d: 344 (w.) GREECE. Borowiec & Salata, 2013: 359 (q.). Senior synonym of lagoi: Salata & Borowiec, 2015b: 15.
 * lagoi. Oxyopomyrmex lagoi Menozzi, 1936d: 278, fig. 7 (w.) GREECE. Junior synonym of krueperi: Salata & Borowiec, 2015b: 15.

Worker
Salata and Borowiec (2015) - (n=25): HL: 0.718 ± 0.014 (0.69-0.76); HW: 0.674 ± 0.017 (0.648-0.715); SL: 0.468 ± 0.015 (0.444-0.503); EL: 0.237 ± 0.013 (0.212-0.263); EW: 0.136 ± 0.009 (0.123-0.153); ML: 0.902 ± 0.036 (0.86-0.983); PSL: 0.17 ± 0.008 (0.156-0.184); SDL: 0.104 ± 0.01 (0.089-0.123); PL: 0.315 ± 0.02 (0.273-0.346); PPL: 0.2 ± 0.02 (0.168-0.223); PH: 0.225 ± 0.016 (0.19-0.273); PPH: 0.217 ± 0.008 (0.201-0.229); PNW: 0.451 ± 0.022 (0.413-0.482); TL: 0.486 ± 0.02 (0.46-0.536); TW: 0.108 ± 0.009 (0.097-0.131); PW: 0.177 ± 0.018 (0.156-0.245); PPW: 0.261 ± 0.024 (0.235-0.346); HI: 93.9 ± 1.49 (91.15-96.9); SI1: 65.2 ± 1.4 (61.8-68.1); EI: 57.7 ± 4.9 (52.3-68.4); SI2: 69.5 ± 1.5 (66.1-72.5); MI: 200.1 ± 8.4 (184.0-214.4); SPI: 163.9 ± 14.3 (140.7-194.4); PI1: 140.2 ± 9.3 (114.7-153.2); PI2: 38.5 ± 1.8 (34.4-41.9); PPI1: 92.4 ± 8.1 (73.3-102.4); PPI2: 57.0 ± 3.2 (49.8-62.9); HTI1: 74.0 ± 4.4 (67.7-82.7); HTI2: 22.3 ± 1.2 (20.2-24.9).

Head, thorax and abdomen black. Antennae black, apex of antennal scapes and first 7 segments of funiculus reddish brown, dorsal surface of promesonotum partly reddish brown. Mandibles black to reddish black. Legs black, apex of femora, tibiae and tarsi reddish brown.

Head rectangular, longer than wide, lateral surfaces below eyes straight, gently rounded on the posterior edges. Anterior margin of the clypeus smooth and slightly curved downward. Eyes longitudinal, strongly narrowing downward, reaching anteroventral margin of head, 0.3 times as long as length of the head. Antennae with 11 segments. Scape short, 0.7 times as long as width of the head, at base 0.8 times as wide as in the apex, gradually widened, slightly bent downward. Funiculus short, 1.5 times as long as scape, first segment elongate, triangular, 1.8 times as long as wide on the apex, 3.0 times as long as second segment, length ratio of segments 100:33:28:33:33:33:67:89:100:144, apical segments 2.0 times as wide as the basal segments. Surface of the scape with very fine microsculpture, shiny, covered with short, dense, appressed to semierect setae.

Promesonotum 1.2 times as long as wide, convex in profile. Promesonotal suture distinct, the border between dorsal and posterior surfaces of the promesonotum sharply curved in profile view. Propodeum quadrate, 1.0 times as long as wide, propodeal spines massive, triangular, erect, only peaks of spines gently curved downward. Petiole rounded with short peduncle, its anterior face straight, node rounded on dorsal surface in profile, posterior face straight, ventral margin of the petiole straight. Postpetiole regularly rounded in profile. Postpetiole 0.9 times as long as wide in dorsal view, regularly widened from base to top, apical half with gently rounded sides.

Mandibles rounded, with outer and dorsal edges straight and smooth, inner margin with 7-8 teeth, the apical tooth long. Clypeus shiny with longitudinal striae on entire surface. Frontal carinae short, extending to 1/3 length of eye; antennal fossa deeply impressed, microreticulate, frontal lobes rugulose with thick longitudinal striae, but shiny between rugosities. Frons shiny, all surface with very thick longitudinal striae and rugulose. Area above eyes with thick longitudinal striae and rugulose, shiny. Ventral surface of the head with striation and rugulose. Sometimes striation very weak, gena shiny and shagreened or microrugulose sometimes with slight longitudinal striae. Entire head bearing setae, posterior margin with dense erect setae directed forward, lateral surfaces of the head with appressed setae directed toward anterior margin, frontal area with dense, appressed to semierect setae placed transversely, directed to the center of the head, ventral surface of the head with a prominent psammophore and appressed to erect long setae. Pronotum punctate to rugulose, shiny, lateral surfaces punctate to rugulose with fine longitudinal striae at the posterior edge. Dorsal suface of the pronotum rugulose to microrugulose, central part usually with weaker sculpture but never smooth, posterior edge sometimes with slightly transverse wrinkles curved at the outer surface. Mesonotum rugulose to punctate with fine longitudinal striae on dorsal surface, lateral surfaces punctate with longitudinal striae at the posterior edge, dorsal surface of propodeum punctate to smooth, shiny, below spiracles punctate with fine longitudinal striae. Dorsal suface of mesosoma with at least 7 long, erect setae on anterior half, mesonotum and anterior propodeum with a few long setae. Base of petiole and postpetiole on the entire surface punctate, node of the petiole punctate on the top and lateral surfaces, postpetiole node punctate, smooth with fine longitudinal striae on the top, covered with several setae. Gaster shiny and shagreened, bearing dense, erect setae.

Legs short, hind femora 0.7 times as long as mesosoma length, hind tibia 0.8 times as long as hind femora, hind tarsi 1.5 times as long as hind femora. Dorsal surface of femora with short, sparse, appressed setae, inner margin with a row of the sparse, long, semierect setae. Tibiae covered with long, appressed to semierect setae on the entire surface, inner margins with a row of appressed setae.

Queen
Salata and Borowiec (2015) - (n=1):HL:0.827; HW: 0.793; SL: 0.492; EL: 0.246; EW: 0.168; ML: 1.358; MH: 0.780; PSL: 0.215; SDL: 0.167; PL: 0.525; PPL: 368; PH: 324; PPH: 291; PNW: 0.682; TL: 0.581; TW: 0.145: PW: 0.235; PPW: 0.356; SI2: 62.0; HI: 95,9; SI1: 59.5; EI: 68.2; MI: 199.1; SPI: 128.7; PI1: 162.0; PI2: 34.5; PPI1: 126.5; PPI2: 52.2; HTI1: 73.2; HTI2: 25.0.

Whole body black, only mandibles partly reddish, antennal scapes reddish-brown with reddish base and apex, funiculus segment 1 reddish, infuscate basally, segments 2-6 reddish with infuscate apical margin, segments 7-10 reddish-brown, tarsi and knees reddish.

Head rectangular longer than wide, lateral surfaces below eyes straight, gently rounded on the posterior edges. Anterior margin of the clypeus softly convex. Eyes longitudinal, strongly narrowing downward, reaching anteroventral margin of head, 0.3 times as long as length of the head. Ocelli large. Scape short, 0.6 times as long as width of the head, at base 0.6 times as wide as in the apex then gradually widened without preapical constriction. Funiculus short, 1.6 times as long as scape, first segment elongate, triangular, 2.1 times as long as wide on the apex, 2.8 times as long as second segment, length ratio of the segments 100:35:35:35:39:52:61:87:78:156, the apical segments 2.1 times as wide as the basal segments. Surface of the scape with very fine microsculpture, shiny, covered with short, appressed to semierect setae.

Mesosoma 1.5 times as long as head, relatively high and robust, very feeble convex with rounded pronotal corners in profile. Scutum 1.3 times as wide as long, posterior margin regularly semicircular. Propodeum located considerably lower than mesosomal plate, propodeal spines triangular, short, broadly attached, rising obliquely upwards. Peaks of spines posteriorly oriented. The spines are linear and parallel-sided in dorsal view. Petiole rounded with long peduncle, its anterior face distinct concave, node globular and shallowly on dorsal surface in profile, posterior face concave. Ventral margin of petiole straight with distinct spine. Postpetiole regularly rounded in profile. Postpetiole 0.9 times as long as wide in the dorsal view, regularly widened from base to top, apical half with gently rounded sides.

Mandibles rounded with distinct longitudinally striation, shiny, inner margin with 7-8 teeth, the apical tooth long. Clypeus rugulose with longitudinal striae, shiny. Frontal carinae short, extending to 1/3 length of eye; antennal fossa deeply impressed, microreticulate, frontal lobes rugulose with thick longitudinal striae, shiny between rugosities. Frons dull, all surface with thick longitudinal striae and dense rugulose. Area between eyes shiny with thick longitudinal striae and dense rugulose. Ventral surface of the head with distinct striation and rugulose, gena shiny, with a fine striation and micropunctation. Entire head bearing setae, posterior margin with a sparse erect setae directed forward, lateral surfaces of the head with appressed to semierect setae directed toward anterior margin, frontal area with dense, appressed to semierect setae placed transversely, directed to the center of the head, ventral surface of the head with a prominent psammophore and appressed to erect long setae. Lateral surfaces of pronotum rugulose to punctate with distinct longitudinal striae, anepisternum rugulose with distinct longitudinal striae, katepisternum smooth and shiny at the centre, finely rugulose with longitudinal striae on the lateral and anterior edges, metanepisternum with distinct longitudinal striae, metakatepisternum rugulose with longitudinal striae. Scutum with longitudinal striae but partly diffused in anterior edge, scutellum smooth to microreticulate with sparse longitudinal striae. Propodeum with sharp longitudinal striae in anterior half of the lateral surfaces, with microreticulation, irregular granulation and few indistinct striae in posterior half, area between propodeal spines smooth and shiny. Dorsal suface of propodeum transversely and diffusely carinate, transversely reticulo-striate between and below the spines. Dorsal suface of mesosoma with dense, semierect and long setae on anterior half, propodeum with a few long setae anteriorly. Base of petiole and postpetiole on the entire surface punctate, nodes of the petiole punctate on the dorsal and lateral surfaces, postpetiole node punctate, sparse punctation and shiny on the top, covered with several setae. Gaster shiny with sparse micropunctation, bearing dense, long, erect to semierect setae.

Legs short, hind femora 0.6 times as long as mesosoma length, hind tibia 0.7 times as long as hind femora, hind tarsi 1.3 times as long as hind femora. Dorsal surface of femora with short, dense, semierect setae, inner margin with a row of the sparse, long, semierect setae, tibiae bearing long, appressed to semierect setae on the entire surface, inner margins with a row of semierect setae

Male
Salata and Borowiec (2015) - (n=1): HL: 0.648; HW: 0.564; SL: 0.419; EL: 0.257; EW: 0.201; ML: 1.626; PSL: 0.223; SDL: 0.167; PL: 0.48; PPL: 0.302; PH: 0.268; PPH: 0.313; PNW: 0.994; TL: 0.96; TW: 0.095; PW: 0.235; PPW: 0.313; HI: 87.0; SI1: 64.6; EI: 78.2; SI2: 74.3; MI: 163.6; SPI: 133.5; PI1: 179.1; PI2: 23.6; PPI1: 96.5; PPI2: 31.5; HTI1: 170.2; HTI2: 9.9.

Whole body uniformly black. Funiculus black, segments 8-12 black to yellowish brown. Tibiae and tarsi black to yellowish brown.

Head oval, longer than wide, below eyes and on the posterior edges rounded. Anterior margin of the clypeus straight. Eyes oval, 0.4 times as long as length of the head. Ocelli large. Scape short, 0.7 times as long as width of the head, at the base 0.6 times as wide as in the apex, straight. Funiculus short, 2.9 times as long as scape, the first segment elongate, triangular, 0.5 times as long as wide on the apex, 1.7 times as long as second segment, length ratio of segments 100:58:42:50:58:75:75:92:92:92:167, apical segments 1.3 times as wide as the basal segments (Figs. 14, 15). Surface of the scape with very fine microsculpture, shiny, covered with short, dense, semierect to erect setae.

Mesosoma 2.5 times as long as head, relatively high and robust, very feeble convex in profile with rounded pronotal corners. Scutum 1.0 times as wide as long, posterior margin regularly semicircular. Propodeum located considerably lower than mesosomal plate, propodeal spines lobe-like, short. Petiole rounded with long peduncle, its anterior face straight, node sharply rounded on dorsal surface, posterior face sharply bent. Ventral margin of the petiole straight, without lobe. In dorsal view, petiole almost parallel sided before petiolar node, then gently widened. Postpetiole 0.7 times as long as wide in dorsal view, regularly widened from base to top, apical half with gently rounded sides.

Mandibles rounded with distinct longitudinally striation, shiny, inner margin with 4-5 teeth, the apical tooth massive and long. Clypeus with longitudinal striae, shiny. Frontal carinae curved outward to merge with the rugae that surround antennal sockets; antennal fossa impressed, shiny with striation, frontal lobes rugulose with longitudinal striae, shiny between rugosities. Frons rugulose with longitudinal striae, area above eyes and ventral surface of the head rugose with vertical striation. Gena shiny with a fine striation. Entire head bearingsetae, posterior margin with dense, very long, semierect to erect setae directed forward, lateral surfaces of the head with dense, long, semierect setae directed toward anterior margin, frontal area with dense, semierect to erect, long setae placed transversely, directed toward center of the head, ventral surface of the head with a prominent psammophore and appressed to erect long setae. Sides of the pronotum rugulose with longitudinal striae, anepisternum smooth and shiny, only anterior edge with fine longitudinal striae, katepisternum smooth and shiny at the central part, rugulose and oblique striation directed toward anterior margin on the side and the posterior edges, metanepisternum rugulose with longitudinal striae, metakatepisternum distinct rugulose with longitudinal striae. Scutum rugulose with longitudinal striae except three longitudinal stripes located at the centre and outer edges of the scutum which are smooth and shiny with several longitudinal striae. Central stripe thin, reach only half of the length of the scutum. Scutellum dull, rugose with longitudinal striae. Metanotum punctate to rugose, shiny. Propodeum on lateral surfaces distinct rugulose with longitudinal striae, area between propodeal spines shiny and smooth. Dorsal suface of the propodeum punctate to rugulose, between and below the spines smooth and shiny. Dorsal suface of the mesosoma with dense, long, erect setae on anterior half, anterior propodeum without setae. Base of petiole and postpetiole punctate on the entire surface, nodes of the petiole punctate on lateral surfaces, dorsal surface of the petiole node punctate with a few longitudinal striae, postpetiole node rugulose to punctate, smooth on the top, micropunctae at the edges, shiny. Gaster shiny with microreticulation, bearing sparse, long, semierect to erect setae.

Legs short, hind femora 0.6 times as long as mesosoma length, hind tibia 0.9 times as long as hind femora, hind tarsi 1.7 times as long as hind femora. Dorsal surface of femora with several, short, semierect setae. Inner margin with a row of the sparse, long, semierect setae. Tibiae bearing long, semierect setae on the entire surface, inner margins with a row of semierect setae

Type Material
Salata and Borowiec (2015) - Lectotype worker (top on the pin) (present designation): O. Krüeperi Forel Salonique coll. aride Sp. O. Krüperi Forel TYPUS Coll. Forel. ANTWEB CASENT 0907759; 2 paralectotype workers: the same data as lectotype (MHNG).

References based on Global Ant Biodiversity Informatics

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