Bonn. zool. Beitr. Bd. 47 H. 1-2 S. 87—94 Bonn, September 1997 Recognition of a sibling species of the Australian Eutermiphora abdominalis Lea (Díptera: Phoridae) R. H. L. Disney Abstract. Eutermiphora watsoni sp. n. is distinguished from the type species of the genus,E. abdominalisLea 1911. Thefemalesofbothspeciesliveinthecolonies ofNasuti- termesfumigatus (Brauer 1865) in New South Wales. Thetaxonomic significance of the position ofthepre-apical setae ofthe palps is discussed, with particular reference to the problem of theaffinities of the Termitoxeniinae. Key words. Díptera, Phoridae, new species, Isoptera, Termitidae. Introduction The aberranttermitophilous genus EutermiphoraLea (1911) (Díptera: Phoridae) was established for a single female from a termite's nest at Sydney, New South Wales, Australia. Unfortunately Lea overlooked both the wing stumps and halteres that, in mature females, are concealed beneath a forward extension ofthe anterior region of the abdomen that covers much of the thorax. The result was to cause confusion in keys to genera and in attempts to determine the affinities of this genus, apart from its assignment to the Metopininae. Lea's description is very brief and has a single sketchy figure of the whole fly. Beyer's detailed, but turgid, redescription, based on two femalesfrom Victoria, is longerbut devoid offigures. Furthermorehe also over- looked the halteres and wing stumps. Seven females ofEutermiphora from a colony of Nasutitermesfumigatus (Brauer 1865) at Braidwood, New South Wales, allowed recognition that the mature females retain halteres and wing stumps (it being proba- ble that the young females shed their wing membranes upon entering the termite colony, as with Termitoxeniinae). In the light of this discovery, an illustrated re- appraisal of the genus was provided (Disney 1989). On a recent trip to Australia I collected a single female Eutermiphora from a colony ofNasutitermesfumigatus at Berowra, north ofSydney. On slidemountingthis specimen, it provedto be a sibling species ofthe series from Braidwood. I therefore borrowedthe type ofE. abdomina- lis. The specimen from Berowra is conspecific. It is concluded that the series from Braidwood constitutes a hitherto unrecognised sibling species. It is named below, its description augmented and its distinction from E. abdominalis specified. The genus Eutermiphora is characterised by Disney (1989) and included in the latest key to the genera of the Phoridae of the world (Disney 1994). It is currently only known from mature, flightless-stage, females. 88 R. H. L. Disney — Figs 1 2: Eutermiphorafemales, glandopenings (g) atrearofdorsal faces offifthabdominal segments. 1, E. watsoni; 2, E. abdominalis. (Scale bars = 0.1 mm). Eutermiphora abdominalis Lea, 1911 EutermiphoraabdominalisLea, 1911: 77. Holotype 9 AUSTRALIA, NewSouthWales, Sydney (South , Australien Museum, Adelaide) [examined]. Beyer, 1966: 214. 2 9, AUSTRALIA, Victoria, Echuca, 1. 1. 1936. (National Museum of Victoria, Melbourne) (the specimens appear to have been lost). Lea (1911) provided asinglefigure ofthewhole fly. His holotypeisnowremounted on a slide. The principal difference from the newly-recognised species is in the hairing and microtrichia of the abdomen (see below). The microtrichia are exceptionally small and densely crowded (Fig. 5). The measurements in Beyer's redescription allow recognition that his specimens belong to this species. Female (Figs 2, 5, 8, 10-11). A sibling species of Eutermiphora abdominalis 89 Figs 3—6: Eutermiphora females, abdominal hairs andmicrotrichiaon dorsal face. 3, E. wat- ssoonnii,, fbiafsteh soefgmbreinstt;le4,onE.sweagtmseonnti,3.th(iSrcdalseegbmaernst;=50,.1E.mambdofmoirna3l—is5,afnidfth0.s0e1gmmenmt;fo6,rE6.).wat- Thehost reported forthisspecies byLea (1911) was "Eutermesfumipennis", nowcalledNasu- titermesfumipennis (Walker). However, this species is now known not to occur in Australia andWatson&Gay (1980) suggestedthatmostAustralianrecords ofthis specieswereprobably really Nasutitermes exitiosus (Hill) or, in a few cases, N. walked (Hill). However, there is a single soldier termite mounted with Lea's holotype of this fly. I have now identified this termite as N. fumigatus. New material examined: 9, New South Wales, Berowra, 7. VI. 1995 (R. H. L. Disney), in galleries ofNasutitermesfumigatus in log. 90 R. H. L. Disney Eutermiphora watsoni sp. n. Eutermiphora abdominalis Disney 1989: 435. Misidentification — Female—only known (Figs 1, 3—4, 6 7, 9, 12) The figures supplement those given elsewhere (figs 1 5 inDisney 1989, figs 6.Id, 8.46a—b in Disney 1994). Thisspecies is alittle largerthan E. abdominalis. The third segment ofthe arista is at least 0.2 mm long, but is nearer 0.1 mm in E. abdominalis. The apical bristle of the palp is longer than the subapical bristle, but is shorter than the subapical in E. abdominalis. The hairs of the dorsal face of the abdomen areless sharplydividedintotwo distinctseries, oflongbristle-likehairs and short hairs. There is a more continuous gradation from long to short hairs (cf Figs 1 and 2). A clear difference is that the microtrichia ofthe upper faces of abdominal segments 2—6 are much larger and fewer in number (Figs 3—4), only being at all dense in the vicinity of the gland opening (g in Fig. 1) at the rear ofsegment 5. Especially on segment 2, these microtrichia tend to be arranged in irregular transverse rows (as in Fig. 1). The me—tatarsi of the front and hind legs are more elongated than those of E. abdominalis (Figs 7 10). Etymology: The species is named in memory ofthe late Dr J. A. Watson, who gave me valua- ble information and publications on Australian termites. Holotype 9 AUSTRALIA, New SouthWales, about 12 miles west of Braidwood, from nest , of Nasutitermesfumigatus, 11. V. 1960 (F. J. Gay) (Australian National Insect Collection, CSIRO, Canberra). 6 9 paratypes, samedata as holotype exceptthree depositedin University Museum of Zoology, Cambridge. Discussion The achievement ofa satisfactory supra-generic classification ofthe Phoridae is still a long way off, and is the subject of current controversy. The subfamilies Termi- toxeniinae and Thaumatoxeninae are well circumscribed, buttheir affinities with the rest ofthe family remain obscure (Disney & Kistner 1992, 1995). The Aenigmatiinae are probably a polyphyletic assemblage reflecting convergent evolution. The largest subfamily, the Metopininae, embraces the probably monophyletic Megaseliini, the almost certainly polyphyletic Beckerinini and the probably paraphyletic Metopinini. The remaining subfamily, the Phorinae, is likewise probably paraphyletic. Brown's (1992) proposals designed to rectify some of these defects have served to highlight the latter. However, the proposals themselves have precipitated current controversies (Disney 1993, 1994, Brown 1995, Disney 1995a, 1996). In view of this I highlight an interesting feature of the genus Eutermiphora. The palps carry the pre-apical differentiatedsetae on the external face (Fig. 12), rather thanon the internal face like most Phoridae. The patterns of distribution of these setae in different families and genera is reviewed below. In the Sciadoceridae, the putative sister group of the Phoridae (Cumming et al. 1995), the differentiated setae on the palps are all weak and restricted to the vicinity of the lower margin, but with most being submarginal on the outer face (Fig. 13). In the putative sister group of the Sciadoceridae+Phoridae, the Ironomyiidae, the setae are larger and more numerous and appear to occur on both faces (Figs 1—2 in McAlpine 1967). This iscertainly the case in the supposedly related Lonchopteridae, in which the setae are well developed on both faces of the palp, but are more numerous and stronger on the outer face (Fig. 14). In the presumed basal family of the Cyclorrhapha, the Platypezidae, many generahave no differentiated setae on the A sibling species of Eutermiphora abdominalis 91 palps. Others, e. g. Agathomyia Verrall, have strongly differentiated setae on the lower margin and inner face of the palp. The related Opetiidae, have no differen- tiated setae on the palps. In the Empidoidea differentiated setae on the outer face ofthe palp are common, often withthe apical setae furtherdifferentiated as bristles. The inner face is typically devoid of differentiated setae. Taken overall, the above outgroup comparisons suggest that the groundplan state inthe Cyclorrhaphais possiblywithdifferentiated setaeontheboth faces ofthe palp 92 R. H. L. Disney — — Figs 11 14: 11 12: E—utermiphora females: 11, E. abdominalis, right wing stump; 12, E. watsoni, right palp. 13 14: Left palps: 13, Sciadocera rufomaculata female; 14, Lonchoptera lutea male. (Scale bars =0.1 mm). but more strongly on the outer face, with one or more apical or subapical setae further differentiated as stronger setae or bristles. Thus Lonchoptera possibly represents the groundplan state. Within the Phoridae every variety of palp setal pattern is encountered, but most frequently the setae are on the inner face with the apical bristles differentiated in varying degrees. The condition reported for Eutermiphora (Fig. 12), therefore, is atypical. However, this pattern is characteristic of all Termitoxeniinae (Disney & Kistner 1995). Furthermore, it occurs in some Metopininae. In most Megaseliini the inner face carries the setae and the apex has differentiated bristles, but in a few species the setae are reduced or lost. In many Metopinini also the pre-apical setae are on the inner face; for example Chonocephalus Wandolleck and Echidnophora Schmitz. In the case of the latter, this observation reinforces the finding that the resemblance between Termitoxeniinae and Echidnophora is due to convergence (Disney 1995b). However, the termitophilous metopinine genera Bolsiusia Schmitz A sibling species of Eutermiphora abdominalis 93 and Penthaplus Schmitz, like Eutermiphora, have the pre-apical setae on the outer face of the palp, as does the type genus of the Metopinini, Metopina Macquart. It is possible, therefore, that this feature is a synapomorphy that unites these genera with the Termitoxeniinae. However, we do not know the extent to which this feature may have evolved independently more than once, and even symplesiomorphy cannot be ruled out. These observations on palp setalpattern suggest the hypothesis thatEutermiphora might be phylogenetically related to the Termitoxeniinae. The female's abdominal physogastry, the shortened costa in relation to the shedding of the wing membranes (presumably at the time of entry to the termite host's nest), the lack of axillary bristles on the wing, the reduction in the size and/or density of the microtrichia on the top of the abdomen and the leg chaetotaxy are additional features of resemblance. The mid-mesopleural ridge and the gland opening at the rear of abdominal segment 5 (g inFig. 1) distinguishEutermiphora and allow its assignment to the Metopininae. The tapered labella of the proboscis (fig. 2 in Disney 1989) are very similar to those ofmany Termitoxeniinae. However, this feature is probably not a groundplan feature of the latter subfamily (Disney & Kistner 1995) and so this resemblance most likely represents an example of convergent evolution. The small, subcircular, features clustered around the bases of some abdominal bristles (Fig. 6) invite further investigation. Fresh specimens examined with the scanning electron microscope should establish whether these features are perfora- tions, thus indicating that the associated bristles are probably primitive solutricho- mes that produce a placatory exudate licked up by the host-termite workers (Disney 1995b, Disney & Kistner 1995). So far solutrichome bristles are only known from Termitoxeniinae. The procurement ofthe unknown males ofEutermiphora would be likely to reveal whether the majority of the similarities between this metopinine genus and Termi- toxeniinae are due to affinity or convergence. Acknowledgements I amgratefulto Dr Leigh Miller (CSIRO, Berrimah, N. T.) for theidentificationofthe termi- tes. IthankDrE. G. Matthews (SouthAustralianMuseum, Adelaide) fortheloanoftheholo- type ofE. abdominalisandDr K. Walker (Museum ofVictoria, Abbotsford) for his attempts to locate Beyer's specimens. I thank my cousin John Disney for his hospitalityand for intro- ducing me to the locality where I collected the new specimen that prompted this paper. My work on Phoridae is currently funded by a grant fromthe Leverhulme Trust (London), made to Dr W. A. Foster (Department of Zoology, University of Cambridge) for a Research Associate to work on termitophilous Phoridae, and a grant from the Isaac Newton Trust Trinity College, Cambridge. Zusammenfassung Eutermiphora watsoni sp. n. wird vonE. abdominalis Lea 1911, der bisher einzigen Art und TypusartderGattung, unterschieden. DieWeibchenbeiderArtenlebeninKolonienvonNasu- titermes fumigatus (Brauer 1865) in New South Wales. Die Anordnung der präapikalen Borsten auf den Maxillarpalpen wird als Merkmal erörtert, besonders im Hinblick auf die ungeklärte systematische Stellung der Termitoxeniinae. 94 R. H. L. Disney References Beyer, E. M. (—1966): Neueund wenig bekannte Phoriden, zumeistaus dem Bishop Museum, Honolulu. Pacific Insects 8: 165—217. Brown, B. V. (1992): Generic revision of Phoridae of the Nearctic Region and phyl—ogenetic classification ofPhoridae, Sciadoceridae and Ironomyiidae (Diptera: Phoridea). Mem. ent. Soc. Canad. 164: 1-144. — Brown, B. V. (1995): Response to Disney. J. nat. Hist. 29: 259-264. Cumming,J. M., B. J. Sinclair&D. M—. Wood (1995):—Homologyandphylogeneticimpli- cations of male genitalia in Diptera Eremoneura. Ent. scand. 26: 120—151. Disney, R. H.—L. (1989): Re-appraisal of the Australian genus Eutermiphora Lea (Diptera: Phoridae). Ent. scand. 19: 435—436. — Disney, R. H. L. (1993): Mosaic evolution and outgroup comparisons. J. nat. Hist. 27: 1219-1221. — Disney, R. H. L. (1994): Scuttle Flies: The Phoridae. Chapman & Hall, London, xii + 467 pp. — — Disney, R. H. L. (1995a): Reply to Brown. J. nat. Hist. 29: 1081 1082. Disney, R. H. L. (1995b)—: Convergentevolution betweenEchidnophoraand Termitoxeniinae (Diptera: Phoridae). Syst. Ent. 20: 195-206. Disney, R. H. L. (1996/97): Contin—uing the debate relating to the phylogenetic reconstruc- tion of the Phoridae (Diptera). G. it. Ent. 7: 103-117 [1994], 338 [1995]. Disney, R. H. L. &D. H—.Kistner (1992): Revisionofthetermitophilous Thaumatoxeninae (Diptera: Phoridae). J. nat. Hist. 26: 953-991. Disney, R. H. L. & D.—H. Kistner (1995): Revision of the Afrotropical Termitoxeniinae (Diptera: Phoridae). Sociobiology 26: 115—225. — Lea, A. M. (1911): On anewAustraliangenus ofPhoridae, associated with termites. Proc. McARl.pSionc.e,VicJt..F.(n.(1s9.6)72)4::A76d-e7ta7i.led study of Ironomyiidae (Diptera: Phoroidea). — Can. Ent. 99: 225-236. Watson, J. A. L. & F. J. Gay (19—80): The identities of Termes australis Walker and Termes fumipennis Walker (Isoptera). J. Aust. ent. Soc. 19: 19—25. Dr R. H. L. Disney, Field Studies Council Research Fellow, University Department of Zoology, Downing Street, Cambridge, England.