The species of Trichophthalma ( Diptera : Nemestrinidae ) of Argentina

The genus Trichophthalma (Diptera: Nemestrinidae) was last revised for Argentina in 1939. Since then several species were newly cited or described for this country but no comprehensive treatment of the genus was published. The analysis of our own extensive collections and of the holdings of Trichophthalma at three major entomological collections in Argentina showed that eleven different species of Trichophthalma exist in this country, and that three of these have an unexpectedly ample distribution, including areas unconnected to the southern temperate forests of Patagonia, where all previous records were concentrated. A key for all Argentinean species is provided.

Nemestrinidae are widespread throughout the globe, but they show a higher concentration in some areas: from the Mediterranean to Turkistan, eastern Australia, southern Africa, Chile and Argentina (Bernardi, 1973). Two extant subfamilies, the Nemestrininae and the Hirmoneurinae, are the most widely distributed. Nemestrininae genera are geographically segregated in South America and Australia (genus Trichophthalma), southern Africa (Prosoeca and Stenobasipteron) and the Palearctic region (Nemestrinus and Stenopteromyia, with a branch that, later, reached Africa, giving rise to Moegistorhynchus) (Bernardi, 1973).
Trichophthalma is the only genus of Nemestrinidae that occurs both in Australia (45 species) and South America (21 species) (Bernardi, 1973;1975). This disjunct distribution resembles that of many other taxa with an ancient Gondwanian origin (Raven & Axelrod, 1974;1975 and references therein). In spite of its primitiveness, Trichoph-thalma shows a rather specialized character (shared by all Nemestrininae): the proboscis is always well developed, thus enabling these flies to reach nectar hidden in deep flower tubes. This has lead to reports of flower visitation by tanglewing flies in South America (Edwards, 1930; and South Africa (Marloth, 1908;Goldblatt & Manning, 2000), some of which are remarkable examples of specialized pollination mutualisms (e.g. Manning & Goldblatt, 1995). However, whereas southern African species have received much attention (Johnson & Steiner, 2000;Goldblatt & Manning, 2000 and references therein), the ecology and actual distribution of most southern South American species remain widely unknown (Peña, 1996; but see . The number of Trichophthalma species known for Argentina increased steadily during the past century. On the basis of material collected in the province of Chubut, Lichtwardt (1910) described two species (originally placed in the genus Eurygastromyia), T. murina (Lichtwardt) and a second one that resulted a junior synonym of T. amoena Bigot (nomenclature follows Bernardi, 1973). Edwards (1930) recorded in the province of Río Negro two taxa previously described for Chile, T. philippii Rondani and T. niveibarbis (Bigot) (sub T. glauciventris Edwards), and added a Río Negro record for T. amoena. Stuardo Ortiz (1939) recorded another Chilean species, T. jaffueli Stuardo Ortiz for Santa Cruz, and reported a possible new taxon (Trichophthalma sp., i.e., a formal epithet was not provided) on the basis of three females, one labelled Santa Cruz, Patagonia (nr. 7411) apparently collected by C. Ameghino, another labelled San Jorge, Patagonia (nr. 39371) (unknown collector), and a third labelled Trichophthalma Morenii n. sp. without collector nor locality, but which Stuardo Ortiz (1939) assumed to have been collected by the naturalist Francisco P. Moreno somewhere in the Argentinean Patagonia. In his revision of the Chilean Nemestrinidae Angulo (1971) provided a record for Chubut of his newly described T. tigrina Angulo. In his synopsis of Nemestrinidae Bernardi (1973) recorded for Argentina two other Chilean taxa, T. nubipennis Rondani for the Neuquén province and T. sexmaculata Edwards for Río Negro. He also applied the name T. morenii Stuardo Ortiz to the unnamed species of Stuardo Ortiz (1939), which resulted in a nomen nudum. Later Bernardi (1975) described a new species, T. anguloi Bernardi, on the basis of a male specimen from Argentina (collector and specific locality unknown).
In recent years, studies on the pollination ecology of the Nothofagus southern temperate forests of Argentina led to two further Chilean species being recorded in Neuquén, T. andina (Philippi) and T. porteri Stuardo Ortiz , and to the extension of the known distributions of several other taxa: T. amoena in Neuquén, T. jaffueli in Río Negro and Neuquén (Vázquez, 2002) and T. philippii and T. niveibarbis in Neuquén .  also reported two Trichophthalma morphospecies from Neuquén that could not be unequivocally assigned to any of the known species of the genus. These taxa were provisionally referred to as T. sp. 1 and T. sp. 2 by these authors.
Thus, by 2006 fourteen Trichophthalma nominal species and morphospecies had been recorded for Argentina, of which T. morenii, T. anguloi, T. sp. 1 and T. sp. 2 were apparently exclusive of this country, while the other ten species were also known for Chile. In an attempt to clarify this panorama, we contrasted the published specific descriptions of Trichophthalma with our own collections from Patagonia and with the holdings of this genus kept at three major entomological collections of Argentina.

MATERIAL AND METHODS
Published descriptions (Stuardo Ortiz, 1939;Angulo, 1971;Bernardi, 1975) were compared with the material of Trichophthalma deposited in our own collection at the Facultad de Agronomía, Universidad de Buenos Aires (hereafter: FAUBA) (>50 specimens), and in the entomological collections of the Museo de La Plata (La Plata), the Instituto Miguel Lillo (Tucumán) (hereafter: LILLO), and the Museo Argentino de Ciencias Naturales Bernardino Rivadavia (Buenos Aires) (together, ca. 110 specimens). Additionally we examined photographs of the holotype and the allotype of T. tigrina, deposited in the entomological collection of the Universidad de Concepción, Chile. The metasomal terga (T) are identified with Arabic numerals.

The distribution of Trichophthalma in Argentina
Nine of the species of Trichophthalma previously recorded for Argentina were found among the examined material (Table 1, Figs. 1-9). No material was seen of the enigmatic T. anguloi (which is still known from the type specimen only) and of T. sexmaculata. Except for T. porteri, found only in Neuquén, all other species were recorded for two or more provinces, with a maximum of five provinces in the case of T. jaffueli. The newly reported records extend the area of five of the species: T. andina, T. jaffueli, T. murina, T. nubipennis and T. tigrina.
An unexpected result was the finding of Trichophthalma in areas of Argentina biogeographically unrelated to the southern temperate forests dominated by the Southern Beeches (Nothofagus spp.), the region in which all previous records of Trichophthalma were concentrated. Although the analysis of the zoogeographical implications of this extended distribution of Trichophthalma is out of the scope of this paper, the presence of three Trichophthalma species (T. jaffueli, T. murina and T. nubipennis) in one or two of the provinces Catamarca, Córdoba, Misiones, and Santiago del Estero (Table 1) cates that this genus is by no means restricted to the Nothofagus forests adjacent to Chile, as previously thought. Perhaps it is no coincidence that the species with the widest distribution (T. jaffueli) showed also the highest ecological amplitude among its congenerics in north-western Patagonia .

Trichophthalma tigrina Angulo
When examining the material of Trichophthalma deposited in the Museo Argentino de Ciencias Naturales Bernardino Rivadavia we found the three females used by Stuardo Ortiz (1939) to describe the species that he recognized as new, but he left unnamed (see Introduction), i.e., the one which later Bernardi (1973) referred to as T. morenii. The labels accompanying these specimens exactly correspond to Stuardo Ortiz (1939) specifications, except that the specimen labeled Trichophthalma Morenii n. sp. carries also a label with the number 39373. Interestingly, these specimens exactly matched the Neuquén female specimen we had called Trichophthalma sp. 1 . Moreover, all this material seemed to correspond with the description of T. tigrina (Angulo, 1971), a view which was confirmed by the identification of photographs of our Neuquén material as T. tigrina by Andrés Angulo (pers. comm. 2006). Also, the photographs of the typical material of T. tigrina provided to us by Dr. Angulo leave no doubt about the coincidence of T. morenii, our morphospecies T. sp. 1 and T. tigrina. Perhaps all this would have been detected earlier had Angulo (1971) examined more material of Trichophthalma from Argentina when he revised the genus for Chile, or had Bernardi (1973) examined material of T. morenii and T. tigrina when he revised the world genera of Nemestrinidae. Because Bernardis (1973) main objective was to better define taxa at the generic level, he studied material from many, but not all species recognized in his paper: he studied no material of T. tigrina or T. Morenii. The name T. morenii was arbitrarily attributed to Stuardo Ortiz by Bernardi (1973), and was never made available, so it should be considered a nomen nudum.

Trichophthalma amoena Bigot
The examination of additional specimens of T. amoena Bigot suggested us that the specimen we called T. sp. 2 in a previous study  fell within the phenotypical range of that species. This view was confirmed by the identification of photographs of our Neuquén material as T. amoena by Andrés Angulo (pers. comm. 2006).

New records of Trichophthalma for Argentina
Trichophthalma andina (Philippi x (x) porteri x species Provinces