Hypoponera eduardi

A circum-Mediterranean species known from other regions too, including the Macaronesian and Indian Ocean islands, South Africa, New Zealand, Chile, etc. (Bolton & Fisher 2011; Rigato & Toni, 2011). This species has been found in a wide range of habitats and situations, including under rocks and other objects on the ground, in leaf litter and in rotten wood.

Identification
A member of the punctatissima group. See the nomenclature section below for additional identification details.

Distribution
Bolton and Fisher (2011) - The most broadly recognised continuous distribution of this species in the Palaearctic is circum-Mediterranean, then eastwards through Turkey at least to Turkmenistan and adjacent countries and south to Saudi Arabia (Agosti & Collingwood (1987a), Arakelian (1994), Baroni Urbani (1971), Cagniant & Espadaler (1993), Collingwood (1969), Collingwood & Agosti (1996), Dlussky, et al. (1990), Kugler (1988)). Apart from this eduardi is also well established on the Macaronesian Atlantic islands of the Azores, Madeira, Canary Is and Cape Verde Is (Hohmann, et al. (1993), Collingwood & van Harten (1993), Espadaler (2007), Wetterer, et al. (2004), Wetterer, et al. (2007)). Its presence in New Zealand has been known for more than a hundred years (Brown (1958), Don (2007)) and it is now also known to occur on the Indian Ocean islands of the Comoros, Mauritius, Réunion and the Seychelles, but in the Afrotropical region it has only been recorded from South Africa.

Distribution based on Regional Taxon Lists
Afrotropical Region: Cape Verde, Comoros, Saudi Arabia, South Africa, United Arab Emirates. Australasian Region: New Zealand. Malagasy Region: Mauritius, Réunion, Seychelles. Neotropical Region: Chile. Palaearctic Region: Algeria, Balearic Islands, Canary Islands, Croatia, France, Georgia, Gibraltar, Greece, Hungary, Iberian Peninsula, Iran, Israel, Italy, Malta, Montenegro, Morocco, Portugal, Republic of Macedonia, Russian Federation, Spain, Switzerland, Turkey.

Biology
Based on its distribution in the Afrotropical region, it would appear to be unable to compete with native species in more typically African forest or savannah habitats.

Regional Information
Espadaler (2007) - Canary Islands: A few workers of this widespread Mediterranean species were collected under a stone on a slope of volcanic charcoal (“picón”).

Castes
Worker-queen intercastes (ergatoids), alate queens, and alate and ergatoid males are known to be produced.

Nomenclature

 *  eduardi. Ponera eduardi Forel, 1894d: 15 (w., ergatoid q.) ALGERIA. Emery, 1895b: 61 (q.m.); Forel, 1904f: 421 (ergatoid m.); Emery, 1909: 373 (q.m.); Wheeler, G.C. & Wheeler, J. 1990a: 458 (l.). Combination in Hypoponera: Taylor, 1967a: 12. Subspecies of confinis: Emery, 1895b: 64. Revived status as species: Forel, 1904f: 421. Senior synonym of antipodum: Brown, 1958h: 23; of chilensis, dideroti: Bolton & Fisher, 2011: 47. See also: Emery, 1916b: 109; Wheeler, W.M. 1937c: 59; Brown, 1958h: 24; Baroni Urbani, 1971c: 15; Kutter, 1977c: 27; Atanassov & Dlussky, 1992: 70.
 * antipodum. Ponera antipodum Forel, 1895a: 43 (q., not w.; see Brown, 1958h: 23) NEW ZEALAND. Junior synonym of eduardi: Brown, 1958h: 23.
 * dideroti. Ponera dideroti Forel, 1913j: 203 (w.q.m.) SOUTH AFRICA. Combination in Hypoponera: Bolton, 1995b: 214. Junior synonym of eduardi: Bolton & Fisher, 2011: 47. See also: Arnold, 1915: 78.
 * chilensis. Ponera opaciceps r. chilensis Forel, 1914d: 264 (w.) CHILE. Combination in Hypoponera: Kempf, 1972a: 123. Junior synonym of opacior: Snelling & Hunt, 1976: 66; of eduardi: Bolton & Fisher, 2011: 47.

Bolton and Fisher (2011) - Like other species in the punctatissima group, eduardi produces worker-queen intercastes (ergatoids) as well as alate queens and its dimorphic males consist of an alate and an ergatoid form, although the last has not yet been recorded from New Zealand (Don (2007). The worker-queen intercastes have distinctly larger eyes than the workers (ca 20–30 ommatidia) and the ergatoid males have small eyes (7–8 ommatidia), reduced mandibles and 13-segmented antennae. The polymorphism of both the female and male sexes, and the reproductive biology of eduardi, have been documented by Le Masne (1956). He referred to worker-queen intercastes as major workers, following Forel (1894), and also noted the presence of a less numerous caste intermediate between workers and intercastes that he termed media workers. The relationship of eduardi with the Japanese Hypoponera nubatama Terayama & Hashimoto (1996) should be investigated as the description and figures of the latter, and the forms of its various castes, are very reminiscent of eduardi. Mating behaviour in nubatama has been discussed by Yamauchi, et al. (2001).

H. eduardi is related to Hypoponera punctatissima but the workers and intercastes are immediately separated by their mesopleural sculpture, separate ranges of SI and DPeI, and the presence of an elongate, longitudinal, slightly impressed mid-dorsal line on the head of punctatissima. The mesopleuron is completely covered with fine sculpture in eduardi but is smooth in punctatissima. Also, the punctate sculpture of the propodeal dorsum in eduardi workers is generally somewhat coarser and more dense than that on the pronotal dorsum, whereas in punctatissima the punctures of the propodeal dorsum are almost effaced. In addition to sculpture and cephalic groove, eduardi workers have longer scapes and the petiole node in dorsal view is broader. Compare the indices above with punctatissima SI 75–84, SL/HL 0.62–0.70, DPeI 140–165. For comments on other related species within the group see under Hypoponera nivariana, punctatissima and Hypoponera ragusai.

The ergatoid males of punctatissima and eduardi are very easily distinguished as in punctatissima the head and mandibles are worker-like in shape and the antennae are 12-segmented, with the scape relatively short compared to the worker (SI ca 60–72) but relatively very long for a ponerine male. Ergatoid males of eduardi, on the other hand, have a head that is not worker-like, reduced mandibles and 13-segmented antennae, with the scape extremely short, SI ca 25–30.

Finally, while discussing the New Zealand fauna, Brown (1958), commented that Hypoponera opacior (Forel, 1893) was, “difficult if not impossible to separate from eduardi in the worker and female castes,” and went on to speculate about the synonymy of the two names. Syntypes of opacior (in MHNG) were examined in the course of this study and directly compared to those of eduardi. It was concluded that, though related, eduardi and opacior represent quite different species. In particular, the syntype workers of opacior differ from eduardi as follows.

1 In opacior the mesopleuron is much less densely sculptured, with weak punctulae that are densest on the uppermost and lowermost parts of the sclerite, but almost effaced medially except along the posterior margin; in eduardi sculpture of the mesopleuron is universal and there are no unsculptured areas.

2 In opacior the propodeal dorsum is more or less smooth, with almost effaced vestiges of sculpture only; in eduardi the propodeal dorsum is minutely reticulate-punctate.

3 In opacior the metanotal groove is represented only by a faint vestige across the dorsal mesosoma; in eduardi it is conspicuous and much more strongly developed.

4 In opacior the mesonotal-mesopleural suture is distinct; in eduardi it is only very weakly present at best, and often is absent.

5 In opacior the maximum width of the first gastral tergite in dorsal view is equal to or slightly greater than the width of the second tergite at its midlength; in eduardi the maximum width of the first gastral tergite in dorsal view is less than the width of the second tergite at its midlength.

6 In opacior the petiole has LPeI 34–37, DPeI 188–213; in eduardi LPeI 39–47, DPeI 167–188.

H. opacior is apparently widely distributed in the New World (e.g. Kempf, 1972; Smith, D.R., 1979). No specimens attributable to opacior have been seen in this study from the Afrotropical or West Palaearctic regions. However, an examination of the syntypes of opaciceps chilensis (MHNG) revealed that they were indistinguishable from the syntypes of eduardi in any way, and therefore the name chilensis has been transferred from the synonymy of opaciceps to the synonymy of eduardi. The establishment of this identity indicates that the tramping ability of eduardi extends to the New World.

Worker
Bolton and Fisher (2011) - Measurements: HL 0.63–0.70, HW 0.54–0.59, HS 0.615–0.640, SL 0.47–0.54, PrW 0.39–0.46, WL 0.86–0.91, HFL 0.50–0.54, PeNL 0.16–0.18, PeH 0.35–0.44, PeNW 0.28–0.32, PeS 0.277–0.310 (30 measured). Indices: CI 82–86, SI 86–93, PeNI 67–75, LPeI 39–47, DPeI 167–188.

Eyes small but conspicuous, of 1–7 ommatidia that are irregular in size and may be partially fused, located far forward on the side of the head. Median portion of anterior clypeal margin shallowly convex, not indented. Dorsum of head with a short median impression that terminates just behind the frontal lobes; without a fine impressed line that extends well beyond the midlength of the vertex. Apex of scape, when laid straight back from its insertion in full-face view, touches or slightly exceeds the midpoint of the posterior margin; SL/HL 0.72–0.78. Reticulate-punctulate sculpture of cephalic dorsum fine and dense. Mesonotal-mesopleural suture sometimes absent but often with a vestige present. Mesopleuron sculptured, densely punctulate-shagreenate to extremely finely striolate everywhere; entirely lacking smooth, unsculptured areas. Metanotal groove conspicuous on dorsum of mesosoma; mesonotum with a well-defined posterior margin. Propodeum bluntly marginate between declivity and sides. Propodeal dorsum minutely reticulate-punctate, usually stronger towards the sides than medially. Side of propodeum, above the spiracle, finely reticulate-punctate. In profile the anterior margination of the mesopleuron angulate behind base of anterior coxa. Petiole in profile with the anterior and posterior faces of the node more or less parallel, at most very weakly convergent close to the dorsal surface. Subpetiolar process in profile without sharp angles anteriorly or posteriorly. In dorsal view the petiole node distinctly broader than long. Maximum width of first gastral tergite in dorsal view less than the width of the second tergite at its midlength. Base of cinctus of second gastral tergite smooth in dorsal view, without cross-ribs dorsally though one or two may occur laterally; descending surface of posttergite that forms the posterior surface of the cinctus sometimes weakly sculptured. Posttergite of second gastral segment, from posterior margin of cinctus to apex, much broader than long. Disc of second gastral tergite finely and densely superficially reticulate-punctulate, appearing microreticulate. Full adult colour dark brown to almost black.

Type Material
Bolton and Fisher (2011):

Syntype workers and worker-queen intercastes (ergatoids), ALGERIA: Oran, Forêt de Msila, 1893 (A. Forel) [examined].

Ponera antipodum Holotype queen (not worker, see Brown, 1958: 23), NEW ZEALAND: Rotorua (Brauns) (MHNG) [not seen].

Ponera dideroti Syntype worker, queen and male, SOUTH AFRICA: Cape Prov., Knysna (as Nynsna in description), no. 159 (H. Brauns) (MHNG) [examined].

Ponera opaciceps r. chilensis Syntype workers, CHILE: Valparaiso (H.-G. Brameld) (MHNG) [examined].