BIOTAXONOMY OF TEPHRITOIDEA Isr. J. Entomol. Vol. 35-36, 2005/6, pp. 367-422 A Revision of the Gymnosagena group of genera (Diptera: Tephritidae: Tephritinae) Amnon Freidberg1 and Bernhard Merz2 ABSTRACT The three Afrotropical genera of Tephritidae comprising the Gymnosagena group are revised: Elgonina Munro (including E. fuscana Munro, E. refulgens Munro, and seven new species: E. dimorphica, E. flavicornis, E. inexpectata, E. infusctata, E. pollinosa, E. splendida and E. yaromi); Gymnosagena Munro (including G. unicornuta Munro and four new species: G. campiglossina, G. kakamega, G. longicauda and G. nyikaensis), and Marriottella Munro (including M. exquisita Munro and M. sepsoides n. sp.). A lectotype is designated for Gymnosagena unicornuta. A cladistic analysis of the group supports the current classification. 1Department of Zoology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv 69978, Israel. E-mail: [email protected]; 2Departement d’Entomologie, Museum d’Histoire Naturelle, C.P. 6434, 1211 Geneve, Switzerland. E-mail: [email protected] BIOTAXONOMY OF TEPHRITOIDEA INTRODUCTION The three small, Asteraceae-feeding, Afrotropical genera of Tephritini, Gymnosagena, Marriottella and Elgonina, revised here, were all originally described by Munro (in 1935, 1939 and 1957, respectively) and later included in the Spathulina genus group of Tephritini (Tephritinae) (Norrbom et al., 1999). To date Gymnosagena includes one species, Marriottella – one species, and Elgonina – two species, and nothing on the taxonomy of these genera has been published subsequent to their original description. All three genera are characterized by a shiny black abdomen, a character shared with only a few other genera of Tephritini (see key below). Outside Tephritini, a shiny black abdomen is known in most Tephrellini (Tephritinae)(including the Platensinini sensu Norrbom et al. (1999)), a non-Asteraceae- feeding group restricted to the Old World. Outside Tephritinae there are many species with a shiny black abdomen, especially within the frugivorous and leaf-mining Trypetinae and the biologically diverse Acanthonevrini (Phytalmiinae). Species of Gymnosagena, Marriottella and Elgonina are also characterized by a short posterodistal lobe of cell bcu, or no such lobe at all; often only one orbital seta; and often a reduced wing pattern or no pattern at all. Together with nine other, mostly Afrotropical, genera they comprise the Spathulina group (Norrbom et al, 1999). The Spathulina group, however, has never been studied comprehensively, and no clear synapomorphies have been identified. Rather, relationships have been established in a so-called “serial” fashion, with one genus (e.g., Gymnosagena) considered similar and closely related to Spathulina Rondani, and another genus (e.g., Elgonina) added because it was considered related to Gymnosagena, and so on. Our working hypothesis was that these three genera together form a monophyletic subgroup within the Spathulina group that is tentatively called here the Gymnosagena subgroup. Nevertheless, the phylogenetic relationships within this subgroup and between it and other Tephritini are not well understood, and the exact composition of the Spathulina group will probably be redetermined only after a revision of Spathulina and other related genera. As Spathulina is species rich (Norrbom et al, 1999; Freidberg, unpublished data), it is not included in the present study. However, it is highly likely that after a comprehensive revision of the Spathulina group, the Gymnosagena subgroup will no longer prevail as an independent group. In the course of our on-going studies on Afrotropical Tephritidae, it has become evident that all three genera contain additional undescribed species. The purpose of the present publication is to revise the Gymnosagena subgroup on both species and generic levels, including a cladistic analysis. We also provide a key to Tephritini genera containing species with a shiny black abdomen. Labels are cited verbatim, except when annotated differently, e.g., collector names are spelled with only first letter capitalized. Authors of host plants are cited in Table 1. The following acronyms appearing on labels are cited verbatim, as are entire holotype labels: N = North, NE = North East, etc. Rt. = Route, nr = near, Km = Kilometer, m = meter; ft = feet, Mt(s) = Mountain(s). Terminology essentially follows McAlpine et al. (1981) and White et al. (1999). The tergal- oviscapal measure [“oviscapal measure” in this publication] of females is the number of terga immediately preceding the oviscape with combined length equal to length of the oviscape (Freidberg and Mathis, 1986). Two ratios are used for the pterostigma: 1. pterostigma ratio = pterostigma length divided by pterostigma width, and 2. pterostigma-costal-cell ratio = pterostigma length divided by costal cell length. The term ‘caudal flange’ refers to the flange borne on the posteroventral aspect of 368 Freidberg and Merz / Revision of the Gymnosagena group the epandrium and seen best when the epandrium is viewed in lateral view. The term ‘pre-glans part’ of the distiphallus refers to the distalmost part of the distiphallus immediately proximal to the glans. The word “dark”, unless accompanied by a color, usually means (e.g., for setae, setulae and wing pattern) brown to black. Likewise the word “pale” usually means white to yellow or gray. Body size is represented by wing length which is given at the end of each species description. Scutum width is measured at the level of postalar setae. Descriptions are composite; characters common to all species of a genus are mentioned in the generic description and not repeated in the species description. The cladistic analysis, including explanation of the methodology, comprises the last part of this chapter. The collections that loaned material for this study and their acronyms (curator names in parenthesis) are as follows: BMNH — Natural History Museum, London, UK (Mr. N. Wyatt) IST — Institute Scientifique, Antananarivo, Madagascar (Curator unknown) MNNG — Naturhistorisches Museum, Geneva, Switzerland NMB — Naturhistorisches Museum, Basel, Switzerland (Dr. M. Brancucci) NMP — Natal Museum, Pietermaritzburg, South Africa (Dr. B. Stuckenberg) SANC — National Collection of Insects, Pretoria, South Africa (Dr. M. W. Mansell and Ms. Ros Urban) TAUI — Zoological Museum, Tel Aviv University, Tel Aviv, Israel ZIL — Museum of Zoology, Lund University, Lund, Sweden (Dr. R. Danielsson) Paratypes of species represented by long series will be distributed among the following three collections: National Museum of Natural History, Smithsonian Institution, Washington, D.C., USA; Natural History Museum, London, England; and National Collection of Insects, Plant Protection Research Institute, Pretoria, South Africa. TAXONOMY The genera, species groups and species in this section are treated alphabetically. For the construction of the following key, specimens of all the genera except Paraspathulina were studied by the authors. The large included genera, Trupanea and Tephritis, contain only very few species with shiny abdomen. Key to genera of Tephritini with partly or completely shiny black abdomen 1. Basal section of costa strongly arched; frons, face, parafacial and gena unusually wide; thorax mostly shiny, with indistinct bands of microtomentum medially; male with lateral membrane of abdomen seen in dorsal view and tergites unusually narrow (as in many Myopitini) (Palaearctic).......................................................................... Placaciura Hendel -. Different combination of characters; costa and male abdomen different............................ 2 2. Head about 1.5 times as long as high; proboscis long geniculate and nearly as long as thorax and abdomen combined (Namibia) ..................................................... Euryphalara Munro -. Head and proboscis not so elongate; proboscis at most about half as long as body ........... 3 3. Thorax and abdomen entirely and strongly shiny black; wing pattern extensively black, comprised of partly connected transverse and oblique bands alternating with hyaline transverse and oblique bands (Lesotho) ............................................... Peratomixis Munro 369 BIOTAXONOMY OF TEPHRITOIDEA -. Thorax usually distinctly microtrichose, not strongly shiny; in doubtful cases, wing not extensively black ................................................................................................................. 4 4. Palpus black; only basal scutellar seta present; only one orbital seta present; halter black; posterior notopleural seta dark brown to black; wing pattern reduced: at most cells bc, c, pterostigma, spot at tip of vein R2+3 and border around crossvein DM-Cu infuscated (South Africa)................................................................................................... Marriottella Munro -. Palpus mostly or entirely yellow; halter yellow (black only in some Tephritis, but then with 2 orbital and 2 scutellar setae); other characters variable.................................................... 5 5. 3 concolorous frontal setae present; only basal scutellar seta present; 2 orbital setae present; posterior notopleural seta pale (Cosmopolitan) ..................................... Trupanea Schrank (shiny abdomen only in species of the former Urelliosoma Hendel; mostly south and east Mediterranean) -. 2 concolorous frontal setae present; other characters variable ...........................................