Aphaenogaster fiorii

Monogynous. In captive colonies, sexuals began to leave the nest from the second week of July to the first week of August, but no attempt to form an actual nuptial flight was detected (Alicata 1999, Alicata and Schifani 2019)

Identification
Salata and Borowiec (2018) - A member of the Aphaenogaster subterranea group.

Alicata and Schifani (2019) - Morphological evidence suggests that A. fiorii, A. trinacriae and A. siculasicula (= subterraneosplendida) are a poor fit for any of the existing Aphaenogaster species groups in the region where they occur. They are more similar to congeners from the Maghreb region, i.e., northwestern Africa, than European Aphaenogaster species.

Worker Yellow color of the body and appendages and the darker first gastral tergite are distinctive and different from most sympatric Aphaenogaster species. The one exception, Aphaenogaster splendida, can appear similarly colored at first sight but has a mesosoma that is much more elongated. Lightly colored young workers of other species or specimens with poorly preserved color can all be excluded by examining the mesosoma in lateral view: A. fiorii lacks the marked metanotal groove in Aphaenogaster subterranea, the distinctive promesonotal suture of Aphaenogaster trinacriae, and the mesonotum less rounded and less convex than in A. sicula (= Aphaenogaster subterraneosplendida) or Aphaenogaster trinacriae.

Among North African species, none shares the unique mesonotal shape or color pattern of A. fiorii. In addition, Aphaenogaster crocea, two of its subspecies (A. crocea croceoides and A. crocea splendidoides), and Aphaenogaster strioloides are considerably more sculptured.

Queen As with the other castes, the color pattern of the yellowish queen of A. fiorii is unique among sympatric Aphaenogaster (even A. splendida is more reddish and also bears a well-defined transverse black stripe on the gaster). The mesosoma shape differs from co-occurring species and only shares a significant similarity to A. trinacriae, A. sicula (= subterraneosplendida) and A. subterranea. All of these differ in their color as well as the shape and length of their spines: in A. fiorii the spines are both long and thick.

Male The male of A. fiorii has a yellowish-brown color (except the head) not to be confused with any other sympatric species if color is well preserved. In addition, only some Aphaenogaster males present a mesosoma with an anterior gibbous part and a comparatively flat posterior part like A. fiorii Among the sympatric species that do so, A. splendida can be easily distinguished at the very first sight by different shape of the metathorax, forming a decisively slenderer area before the propodeum in lateral view. The male of Aphaenogaster sardoa is larger, darker, with a visibly less gibbous anterior part and much more abundant erect setae on the body. Aphaenogaster trinacriae and A. sicula (= subterraneosplendida) present the most similar males, but besides being darker, they do not possess the two tubercles on the propodeum as pronounced and with the same shape. In the case of A. siculasicula (= subterraneosplendida) the metathorax also forms a slenderer area before the propodeum, and A. trinacriae is distinguished by the well-developed enlarged flat areas on the sides of the propodeum (better observed in dorsal view). The shape of the mesosoma also distinctively separates A. fiorii from the somewhat similar Maghrebian species: A. crocea, Aphaenogaster faureli, Aphaenogaster mauritanica, Aphaenogaster nadigi, A. strioloides, and Aphaenogaster theryi.

Distribution
Aphaenogaster fiorii is present in Sicily, where it is relatively rare, and the islands of Malta and Gozo (Maltese Islands), where it seems more common. The elevation of the occurrence records range from 5 m to 1,000 m. (Alicata and Schifani 2019)

Distribution based on Regional Taxon Lists
Palaearctic Region: Italy.

Habitat
Alicata and Schifani (2019) - In Malta the species has been frequently collected in thermophilous oak forest and open areas such as a meadow on a clay soil, a very small coastal area with Limonium melitense surrounded by a road and a touristic facility, and within an area with synanthropic vegetation near crops. Moreover, it was also collected in a Mediterranean maquis. Baroni Urbani A. fiorii collected in areas with a relatively large percentage of organic matter, such as anthropogenic areas characterized by trees, shrubs or herbaceous cover. In Sicily, it was found in oak forests and even indoors in a country house, always at higher altitudes than in the Maltese islands.

Nomenclature

 * . Aphaenogaster gibbosa subsp. fiorii Emery, 1915a: 258 (w.) ITALY (Sicily).
 * Alicata & Schifani, 2019: 3 (q.m.).
 * Combination in Aphaenogaster (Attomyrma): Emery, 1921f: 58.
 * Subspecies of gibbosa: Emery, 1916b: 130; Emery, 1921f: 58; Kutter, 1927: 98; Santschi, 1932d: 344; Baroni Urbani, 1971c: 49; Bolton, 1995b: 69; Poldi, et al. 1995: 3.
 * Status as species: Alicata & Schifani, 2019: 3 (redescription).

Description
The following information for the three castes is based on a redescription by Alicata and Schifani (2019).

Worker
(42 individuals, 8 localities): HL: 1.14 ± 0.06 (1.05–1.27); HW: 0.97 ± 0.07 (0.82–1.15); CI: 85.28 ± 2.66 (78.57–93.75); FW: 0.85 ± 0.06 (0.75–1.00); SL: 1.23 ± 0.6 (1.12–1.37); SI: 126.48 ± 4.93 (117.77–139.39); MW: 0.61 ± 0.04 (0.52–0.75); ML: 1.53 ± 0.08 (1.37–1.75).

Whole body yellow except for first gastral segment which is darker. Head subrectangular, lateral margins under eyes slightly rounded, posterior margin of head straight. Anterior margin of clypeus gradually convex, mandibles rounded. Antennae with twelve segments, antennal club with four segments. Promesonotal suture only slightly marked, the two forming almost continuous dorsal profile in lateral view. In lateral view dorsal profile of metanotum presents slight depression or it is straight. Dorsal profile of propodeum mostly straight, spines variable in size but always well-defined, often oriented upwards. Sculpture relatively weak and shiny in general. Head finely reticulated with longitudinal striae mostly limited to lateral areas under eyes, sparsely present above eyes and variably on mandibles. Mesepisternum and propodeum reticulated with fine longitudinal striae, pronotum finely imbricate, gaster smooth, petiole and postpetiole finely imbricate to reticulate. Suberect and erect setae sparse all over head, decumbent setae on mandibles, adpressed setae on scapes and adpressed to subdecumbent setae on flagellomeres. Long setae extending down from clypeus. Erect setae over dorsal surface of mesosoma, petiole and postpetiole, and all over gaster. Mostly adpressed, partly suberect setae on legs, with sparse erect setae on coxae and femora.

Queen
(4 individuals, 2 localities): HL: 1.48 ± 0.04; HW:1.46 ± 0.03; CI: 98.75 ± 0.01; FW: 1.25 ± 0.04; SL: 1.42 ± 0.04; SI: 97.42 ± 1.01; MW: 1.35 ± 0.03; ML: 2.53 ± 0.04.

Whole body yellowish, with darker areas on gaster. Head subrectangular, lateral surface below eyes slightly rounded, posterior margin of head straight. Anterior margin of clypeus slightly convex, mandibles rounded. Antennae with twelve segments, antennal club with four segments. Pronotum rounded in dorsal view, propodeal spines relatively long, horizontal and with wide base. Petiole with long peduncle and node convex on both sides, postpetiole with anterior concave side and posterior slightly convex side. Entire head, except clypeus and occipital margin, densely covered with longitudinal striae. Long and more marked striae are subparallel to each other. Between them, less marked striae can be found often crossing each other. Mesosoma mostly shiny, with horizontal striae appearing in proximity of sutures, across propodeum and posterior faces of petiole and postpetiole. Adpressed to decumbent setae on antennae, suberect to mostly erect setae on head, dorsal part of mesosoma, of petiole and postpetiole and all over gaster. Long setae extending down from clypeus. Adpressed to decumbent setae on legs.

Male
(3 individuals, 1 locality): HL: 0.68 ± 0.01; HW: 0.72 ± 0.02; CI: 106.12 ± 4.31; FW: 0.46 ± 0.01; SL: 0.20 ± 0.00; SI: 27.60 ± 0.95; MW: 0.82 ± 0.02; ML: 1.67 ± 0.04.

Whole body yellowish except for head which is dark brown. All appendages paler than rest of body. Head subtrapezoidal, occipital margin rounded, anterior margin of clypeus convex, eyes large and oval. Antennae with thirteen segments, antennal club with five segments. Mesosoma elongated, with anterior gibbous part formed by prothorax, mesothorax and part of metathorax, and posterior part comparatively flat formed by part of metathorax and propodeum. Promesonotal suture well marked, pronotum and mesonotum convex in lateral view, rounded on side. Metathorax arched, consisting of subvertical and subhorizontal part. Subhorizontal part, in dorsal view, becomes very narrow in proximity of subvertical part. Propodeum not much thicker than horizontal part of metathorax in lateral view. Propodeal spines are absent and only represented by two tubercles. Petiole elongated, petiolar node and postpetiolar node rounded, both dorsally presenting shallow longitudinal suture in center. Scape very short, covered by rare decumbent setae, decumbent to subdecumbent setae also present on head, mesosoma and legs, a few erect setae on mesosoma, coxae, petiole and postpetiole and suberect to erect setae on gaster. Head finely reticulated, rest of body smooth and shiny.

References based on Global Ant Biodiversity Informatics

 * Alicata A., and E. Schifani. 2019. Three endemic Aphaenogaster from the Siculo-Maltese archipelago and the Italian Peninsula: part of a hitherto unrecognized species group from the Maghreb? (Hymenoptera: Formicidae: Myrmicinae). Acta Entomologica Musei Nationalis Pragae 59: 1-16.
 * Baroni Urbani C. 1968. Studi sulla mirmecofauna d'Italia. IV. La fauna mirmecologica delle isole Maltesi ed il suo significato ecologico e biogeografico. Ann. Mus. Civ. Stor. Nat. Giacomo Doria 77: 408-559.
 * Emery C. 1916. Fauna entomologica italiana. I. Hymenoptera.-Formicidae. Bullettino della Società Entomologica Italiana 47: 79-275.
 * Grandi G. 1935. Contributi alla conoscenza degli Imenotteri Aculeati. XV. Boll. R. Ist. Entomol. Univ. Studi Bologna 8: 27-121.
 * Poldi B., M. Mei, and F. Rigato. 1995. Hymenoptera, Formicidae. Vol 102. Checklist delle specie della fauna Italiana: 1-10.
 * Schembri, Stephen P. and Cedric A. Collingwood. A Revision of the Myrmecofauna of the Maltese Islands. 417-442.