Morphological differences between Exechia fusca (Meigen, (Diptera, 1804) and Exechia confinis Winnertz, 1863 Mycetophilidae) Introduction.

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1 III!. J. Dip/erol. Res. 1Of 1 ) 20 March 1999 ISSN An International Journal of Dipterological Research Morphological differences between Exechia fusca (Meigen, (Diptera, 1804) and Exechia confinis Winnertz, 1863 Mycetophilidae) OLA VI KURINA Kurina, O Morphological differences between Exechia fusca (Meigen, 1804) and Exechia collfillis Winnertz, 1863 (Diptera, Mycetophilidae). lilt. J. Dipterol. Res., 10(1): The Inorphological differences between two very closed species Exechia fusca and Exechia confiljis are discussed. The detailed figures of males and females genitals are given. Ola';.:i KltrilJa. Institute of Zoology and Hydrobiology of Tartu UlliGersit)', VallellllJise 46, Tartlt 51014, Estonia; Institltte of Zoolog)' and Botan)' of Estonian Agriculture UlJiGersit)', Riia 181, Tartu 51014, Estonia, e-ll1ail. olagi@zbi.ee Ke)' ro'ords. Diptera, Mycetophilidae, Exechia. Introduction Exechia Winnertz, 1863 is a nul11erous and widely distributed genus among ftmgus gnats. Exechia species are distributed in all zoogeographical regions (Laffoon, 1965; Colless & Liepa, 1973; Matile, 1980, 1996; Hackl11an et ai., 1988; Plassmann, 1995). There are 61 species recorded in Palaearctic region (Hackman et ai., 1988; Zaitzev, 1996). Many species are closely related and they can be distinguished from each other by col11parison of male genitals. Such species are also Exechia fltsca (Meigen, 1804) and Exechia collfillis Winnertz, Chandler (1978) has distinguished Exechia f/lsca group in genus Exechia for nal11ed two species. E. fltsca is a holarctic species (Hackl11an et ai., 1988). E. [ol/fil/is is widely distributed in Europe (e. g. Krivosheina et al ; Hackl11an et al ; Plassnlann & Schlacht, 1990). Both species are associated with the fruit bodies of l11acrofungi. According to Hackl11an and Meinander (1979) E. fllsca is polyphagous species. By Eisfelder (1955) it is registered on 128 species of 111acrofungi in Germany. Chandler (1978) nlentioned this species also on Polyporaceus fungi. E. confinis is recorded on Lactarius piperatus (Plassmann, 1971) and Paxillus involutus (Kurina 1994). By Hackman and Meinander (1979) Exechia sp. pr. confinis has been found regularly on Paxillus involutus. According to literature (e. g. Plassmann, 1989; Grundnlann, 1990) the activity of imagoes is recorded in autumn and winter. In Estonia the owerwintering of the species have been found in caves (Kurina, 1996). Material The 111aterial for the present conu11unication is collected in fronl 27 sites in Estonia. Sweep-netting, collecting by exhauster fronl caves and rearing frol11 nlacrofungi have been used as a 111ethods of collecting. Part ofthe Inaterial is already published (Kurina, 1991, 1994, 1996, 1998), but it is undergoing new critical study. The nlaterial is deposited in the Institute of Zoology and Botany of Estonian Agricultural University It. J. Dipterologi[ol Research /0 /999

2 o. K/lrina: Morphological differences between E.\'echia f/lsca and Exechia collfillis 55 Vault. near Orissaare on SaareIllaa Island and Kallnistu cave in Tartu. Altogether 39 0' and 10 9 speci Inens are exainined. Additi01/aI IIIattria1st"died. E Xtchia co 11fi 11is Winnertz C). Russia. Sablino Tsarskoselsk. u peshcheri. leg. A. Stackelberg, , det. A. Stackelberg Deposited at the Zoological Institute of Acadel11Y of Sciences, St. Petersburg, Russia. Discussion By n1any authors (e. g. Edwards, 1925; Landrock, ; Ostroverkhova, Stackelberg, 1969; Krivosheina et ai., 1986) the essential difference between E. f/lsca and E. confinis is the yellow lateral spots on the first segl11ents of the abdomen of E. col/fillis. The abdol11en of E. fllsca is uniformly blackish brown. Winnertz (1863) reported the yellow spots on the third segnlent of the abdol11en of E. collfi11is. Other authors (e. g. Landrock, 1927; Seguy. 1940; Krivosheina et al ) l11arked the spots on the second segl11ent. Nal11ed characteristic is very variable. in my material few specimens have no Inentioned spots at all or they are indistinct. Morphol11etric measurel11ents are widely variable and overlap for these two species, as presented in Table 1. Stastically, differences can be detected, but these Table 1. Measured lengths of wings and legs of E~f!chia fllsca (n=25) and Exechia confinis (n=25). r-n1, radial-l11edial. crossvei.n; nll?~t., medial petiole; tl' t2' t3' fore. nud and 11lnd tibia; I tars.1, I tars.2,... II tars.l,, III tars.l,, tarsal segl11ents of fore, l11id and hind tarsus. The lengths are in millimeters. 5 7 Mesaured parts E. f"sca E. confinis r m pet tl Itars Itars Itars Itars Itars t Iltars li tars litars Iltars Iltars t Itars. 1 l Illtars Illtars Ill Ill tars [ Figs 5-8. Laterodorsal view of large lateral appendage of gonostylus (5, 6), ventral view of felnale tenninalia (7, 8). 5, 7, Exechia fusca (Meigen, 1804)~ 6, 8, Exechia col/fil/is Winnertz, Scale equal to 0.1 min. 8 Into J. Dipterological Research

3 - ~ O. Kllrilla: ijlorphological dlfferellces betweell Exechia fusca and Exechia collfinis differences have no significance in detennination of species. For both species size and coloration can probably depend on larval nutrition and environ Inental conditions in larval and pupal stages. The best nlethod for species detennination is COlnparison of genitals. Male hypopygiu111s have been figured by: Landrock~ 1927, plate 7, fig., 38; Landrock, 1940, fig.~ 145; Ostroverkhova, 1979, plate 25, fig.~ 8; Krivosheina et ai., plate 41, fig., 1 - E.fusca; Landrock, 1912, fig., 17, 18; 1927, plate 7, fig.~ 25, 1940, fig.~ E. collfinis. Nobody has figured details of inner appendages of gonostylus for both species, they are important for identification too. Felnale genitals have been figured by: Lundstronl, 1909, fig., 113, 114; Chandler, 1977, fig., 28 - E. fusca; Plasslnann, 1970, fig.~ 14; Chandler, 1977, fig., 29 - E. collfillis. More detailed drawings are given by Chandler (1977)~ but only in lateral view. The nlost inlportant difference between fe111ale specitnens are the shape of gonocoxids in ventral view, that nobody has figured yet. Differences in lnale and felnale genitals are analysed in Table 2 with respective referations to the figures. Table 2. Differences between genitals of Exechia fusca (Meigen, 1804) and Exechia co1lfi1lis Winnertz, 1863 Exechia f/lsca iwales Exechia collfillis Medioventral appendage of gonocoxid rounded on apex, 111inimum with depression apex, as twice as long as wide, C0I11- long as wide, conlpare fig. pare fig. 1, A~ 2, A. Inner structure connected with cercus with two bristles on apex, with four bristles on apex, compare fig. I, B~ conlpare fig. 2, B. Large lateral appendage of gonostylus on basis of asetose elongated part without lobe, COlllpare fig. 5; --_._----~-- --_._-_.-... FE.lfALES _ ~-- blunt, compare fig. 7~ Aedeagus with depression on apex, with snlall tllound on apex, compare fig. I, C~ compare, fig. 2, C. Apex of large lateral appendage of gonostylus narrower as inner appen- as wide as inneres appenddages of gonostylus, C0I11- ages ofgonostylus, conlpare pare fig. 3, 0, E~ fig. 4, 0, E. with sl11all lobe, conlpare fig. 6. Apex of gonocoxid ventrally conical, COtllpare fig. 8. Very close to the two species is Exechia styriaca Strobl, The species has been fond only in Austria (3d' 29). According to Strobl (1898), the species is very silnilar to E.col/fil/is~ and by Strobl (1910) to E. fllsca. In Strobl (1898) it is marked~ that the nlost outstanding difference between E. sfyriaca and E. collfillis is almost entirely brown coloration of hind tibia of E. styriaca. Possibly E. styriaca can be synonym to E. collfinis, but confir Ination to this can not be found without type material. Acknowledgements This study has been a part of the research prograin "'Biodiversity of Estonian fauna" in Institute of Zoology and Botany, University of Tartu. I am greatly indebted to Mr. Mart Jiissi for reading the Inanuscript. References Chandler, P. J Studies of SOlne fungus gnats (Diptera: Mycetophilidae) including nine additions to the British list. SystelJlatic ElItOfllolog)', 2: Chandler, P. J Association with Plants. Fungi. Ill: Stubbs, A. & Chandlar, P. (eds.) A Dipterist's Halldbool. The Afllateur ElItOll1ologists, 15: Colless, D. H. & Z. Liepa Family Mycetophilidae. 111: Delfinado, M. D. & Hardy, D. E. (eds.) A Catalog of the Diptera of the Oriellfal Regioll. VOIUfllf I. Suborder Nefllatocera. Honolulu: Edwards, F. W British Fungus-Gnats (Diptera, Mycetophilidae). With a revised Generic Classification of the Family. TrailS. E 11toIII01. Soc. LOlldoll, 73: Eisfelder, I Die haufigsten Pilzwohner. Ztschr. PiI.Z1 1I1lde, 18: 1-5; 19: Grundmann, B Die Pilzmiickenfauna des Hochsauerlandes (Diptera, Nematocera). Decheniana, 143: Hackman, W. & M. Meinander Diptera feeding as larvae on macrofungi in Finland. 1111/. Zool. Fellll., 16: Hackman, W., Lastovka, P., Matile, L. & R. Vaisanen Family Mycetophilidae. Ill: Soos, A. & Papp, L. (eds.) Catalog//t' of Palaearctic Dip/era. Vol. 3. Ceratopogollidae - iw)'cetophilidat'. Budapest: /. J. Dip/erological Research /0 /999

4 O. Kllrilla: ij/orphological differellces belween Exechia fllsca and Exechia confinis 57 Krivosheina, N. P., Zaitzev, A. I. & E. B. Yakovlev IlIsecls as decolllposers offllngi i/l Ihe fon)sl of the Europeall part of USSR. Moscow: 310 pp. (In Russian). Kurina, O Mycetophilidae (Diptera) reared froln Inacrofungi in Estonia. Proc. Estolliall Acad. Sci. BioI.. 40: Kurina, O New records of Mycetophilidae (Diptera) reared from 111acrofungi in Estonia. Proc. Estollia1l Acad. Sci. BioI., 43: Kurina, O Hibernation of fungus gnats (Diptera, Mycetophilidae) in Estonian caves. Stud. Dipterol.. 3: Kurina, O Fungus Gnats in Estonia ( Diptera: Bolitophilidae, Keroplatidae, Macroceridae, Dit 0 n1y iidae. D iadocidiidae, Mycetophi1idae). Dissertiol. L1lliversit. Tartuell.. Tartu, 38: 200 pp. Laffoon, J. L Falllily MycetophiIidae (Fungivoridae). Ill: Stone. A. et a1. (eds.) A catalog ofthe Diptera ofainerica 1Iorth ofif!exico. Washington: Landrock, K Neue oder wenig bekannte Pilzn1iicken. Briell. EIII. Ztg., 31: Landrock, K Fungivoridae (Mycetophilidae). Ill: Lindner, E. (ed.) Die Fliegen der Palaarctischell Region, 8: Landrock, K Zweifliiger oder Diptera. VI: Pilzn1iicken oder Fungivoridae (Mycetophilidae). Ill: DahL F. (ed.) Die Tier-&Jelt Deulschlallds, 38: Lundstrom, C Beitrage zur Kenntnis der Dipteren Finnlands. IV. Supplement Mycetophilidae. Acta Soc. Fau1Ia Flora Fe1l1l., 32: Matile, L Superfamily Mycetophiloidea. 111: Crosskey. R. W. (ed.) Catalogue of tht Diptera of the Afrotropical Rtgioll, London: Matile, L Falllily Mycetophilidae. Ill: Australasian/Oceanian Diptera Catalog - Web version. Last revised , hawaii.org/bishop/ento/aocat/myceto/htnl1, accessed Ostroverkhova, G. P Fungus-gnats (Diptera, Mycetophiloidea) of Siberia. Tonlsk: 308 pp. (In Russian). Ostroverkhova, G. P. & A. A. Stackelberg Mycetophilidae - fungus gnats. Ill: Key ofilisects ofeuropeall part of USSR, Leningrad, 5(1): (In Russian). Plassmann, E Zur Taxonolnie der Fungivoridae (Diptera). Sellci'enbergialla BioI., 51: Plassmann, E Uber die Fungivoriden-Fauna (Diptera) des N aturparkes Hoher Vogelsberg. Oberhessische Natur-&Jiss. Zeitschr., 38: Plassmann, E Winteraktivitat von adulten Pilzllllicken eines Birkenbestandes des ostlichen schleswig-holsteinischen Hiigellandes (Diptera, Nelllatocera, Mycetophilidae). Elltot1l0faulla, 10: Plassmann, E Slidamerikanische Pilzmiicken in der Zoologischen Staatssamlll1ung Mlinchen (Diptera, N ematocera, Mycetophilidae). 1ItOl110 faulla, 16: Plassmann, E. & W. Schlacht Ein Beitrag zur Pilzmiickenfauna Spaniens mit Beschreibung zweier neuer Arten (Diptera, N ematocera, Mycetophilidae). Elltol1l0faulla, 11: Seguy, E Faune de France. Dipteres Nelllatoceres, Paris, 36: 365 pp. Strobl, B. G Die Dipteren von Steiermark. 4 (Nachtr. I). /J/itt. Natur-&J. Fer. Steierlll., 34: Strobl, B. G Die Dipteren von Steiermark. 5 (Nachtr. 11). Mitt..iVatur-&J. Fer. Steierr1l., 46: Winnertz, J Beitrag zu einer Monographie der Pilznliicken (Mycetophilidae). Verh. Zool. Bot. Ges. IV/ell, 13: Zaitzev, A. I Six new species of fungus gnats of the tribe Exechiini from Sakhalin and Kuril Islands (Diptera, Mycetophilidae). lilt. J. Dipterol. Rts., 7: Rectived lilt. J. Dipterological Research 10 /999

5 54 O. K/lril/a: l1orphological differences between Exechia f/lsca and Exechia confinis D B E A 3 ~D B A 2 4 Figs 1-4. Ventral view of gonocoxid (1, 2) and ventral view of gonostylus (3, 4). 1, 3, Exechia f/lsca (Meigen, 1804); 2, 4, Exechia collfillis Winnertz, A - Inedioventral appendage of gonocoxid; B - inner structure connected with cerci; C - aedeagus; D elongated asetose part of lateral appendage of gonostylus; E - inner appendages of gonostylus. Scale equal to 0.1 mm. Exechia fusca (Meigen, 1804) 118 6' and 90 9 specilnens were reared by Ine fron1 27 species (42 fruit bodies) of Agaricales s. I.. Material was collected at Islet of Abruka near Saaren1aa Island, Viidun1ae Nature Reserve, Orissaare on Saarel11aa Island, Puhtu near Virtsu, Vonnsi Island, Oonga southeast of Haapsalu, Rannan1etsa south of Parnu, Nigula Nature Reserve, Tanlsa-Altll1ae near Elva, Vapral11ae northeast of Elva, Tiksoja near Tartu, Jarvselj a southeast of Tartu, Kohala northeast of Rakvere and Varudi northeast of Rakvere. 36 () specil11ens were sweep netted by Ine at Orissaare, Piiri on Muhu Island, Riguldi, Kaselnetsa south of Saku near Tallinn, Oonga, Nigula Nature Reserve Taevaskoja north of Polva, Jarvselja Tiksoja, Rahni near Tartu, Voore east of Jogeva and Kohala. I 6' lilt. J. Dipttrulugical Restarch specinlen was collected by Prof. H. Relnll1 at Kaariku, southwest of Otepaa, but Inethod used is not known. 2 6' speciinens collected by nle with a exhauster from Kahnistu cave in Tartu. Altogether 157 6' and 90 9 specimens are exan1ined. E:>""echia confinis Winnertz, ' and 10<;> specin1ens were reared by Ine fron1 5 fruit bodies of Paxillus involutus, collected at Pallasll1aa on Muhu Island, Oonga, Pikasilla northeast of Torva, Talnsa-Altn1ae and Kohala. 106' specin1ens were sweep netted by 111e at Orissaare Oonga, Nigula Nature Reserve, Melliste southeast of Tartu and Maetaguse south of Johvi. 23 C) specil11ens collected by 111e with exhauster froln Maasi Castle

6 o. Kltrilla: Morphological differences between E:r:echia fusca and Exechia confillis 55 Vault. near Orissaare on Saarelllaa Island and Kal111istll cave in Tartu. Altogether 39 0' and 10 9 speci111ens are exalllined. Additiollal IlIattrial studied. Extchia collfi 11 is WinneI1z '. Russia. Sablino Tsarskoselsk. II peshcheri. leg. A. Stackelberg , de1. A. Stackelberg Deposited at the Zoological Institute of Acaden1Y of Sciences S1. Petersburg, Russia. Discussion By 111any authors (e. g. Edwards, 1925; Landrock, ; Ostroverkhova, Stackelberg, 1969; Krivosheina et ai., 1986) the essential difference between E. fllsca and E. coj/finis is the yellow lateral spots on the first seglnents of the abdolnen of E. collfillis. The abdolllen of E. fllsca is uniformly blackish brown. Winnertz (1863) reported the yellow spots on the third seglnent of the abdomen of E. collfillis. Other authors (e. g. Landrock, 1927; SegllY. 1940; Krivosheina et al ) 111arked the spots on the second seglnen1. Nallled characteristic is very variable. in Iny material few specilnens have no lnentioned spots at all or they are indistinct. Morpholl1etric n1easuren1ents are widely variable and overlap for these two species as presented in Table 1. Stastically, differences can be detected but these 5 7 Table 1. Measured lengths of wings and legs of Exechia fusca (n=25) and Exechia confinis (n=25). r-n1, radial-inedial. crossvei.n; n1j?~t., Inedial petiole; tl' t2' t3' fore. nlld and 11lnd tibia; Itars.l, I tars.2,... II tars.l,, III tars.l,, tarsal seg111ents of fore, lnid and hind tarsus. The lengths are in millilneters. Mesaured parts r-111 m pet. tl Itars. I Itars. 2 Itars. 3 Itars. 4 Itars. 5 t2 Il tars. I II tars. 2 Il tars. 3 II tars. 4 II tars. 5 t3 Illtars. 1 IlI tars. 2 IlI tars. 3 IlI tars. 4 Illtars. 5 E. fusca E. collfinis [ 6 8 Figs 5-8. Laterodorsal view of large lateral appendage of gonostylus (5, 6), ventral view of felnale tenninalia (7, 8). 5, 7, Exechia fllsca (Meigen, 1804); 6, 8, Exechia collfillis Winnertz, Scale equal to 0.1 min. lnt. J. Dipterological Restarch /0 /999