A review of Palaearctic Gymnophora Macquart (Diptera: Phoridae), with description of new species

Palaearctic species of the genus Gymnophora are reviewed. Four new species, G. amurensis sp. n., G. gornostaevi sp. n., G. perpropinqua sp. n., and G. victoria sp. n., are described from the European Russia, Middle Asia, and Russian Far East. Females of two other species from the Far East are described under code letters. G. laciniata Michailovskaya, 1997 is synonymised under G. prescherweberae Disney, 1997. Lectotypes of G. arcuata (Meigen, 1839) and G. verrucata (Schmitz, 1929) are designated. The latter species is redescribed. Palaearctic females of G. nigripennis demonstrate wide variation of taxonomically important features and may, in fact, represent a group of closely related species. One female of G. nigripennis, which has been caught alive, is recorded to be infected with fungi.


INTRODUCTION
The genus Gymnophora Macquart, 1835 comprises more than 50 species recorded from the Holarctic and Oriental regions.European species are covered by Disney (1983Disney ( , 1997)), and Asian species have been treated by Brown (1987Brown ( , 1988)), Liu (1993), andMichailovskaya (1997).However, this genus is still poorly known in the Palaearctic Region.In this paper, we are reviewing Palaearctic species of this genus, with special reference to the territory of Russia and allied countries.Japanese spe cies are satisfactory keyed and illustrated by Brown (1988), and we do not include them unless they are recorded from the mainland.
Representatives of the genus Gymnophora have quite distinctive general appearance and are easily recognisable under low magnification by the reduced frontal, thoracic and costal setation, the slender hind legs with the tibiae lacking of a longitudinal hair palisade, and the large wings (except in the brachypterous G. lapidicola) with a peculiar venation.Male hypopygium is usually with drawn into the abdomen and circumverted 90° counter clockwise.Biological data on Gymnophora are scarce and summarised recently by Brown (1998).

MATERIAL AND METHODS
Females of Gymnophora were studied mounted on slides as has been proposed by Disney (1983).Males were soaked in cold 10% solution ofKOH for several hours, then rinsed in water and alcohol and transferred to a drop of glycerol for further study.Permanently, they are stored in pinned microvials.Occasionally, males have been mounted on slides similarly to females.The drawings were made in transmitted light using a Leica DMLB microscope with drawing attachment.
Terminology of the structures of the aedeagal complex fol lows Brown (1987), although a different opinion has been expressed on the homology of some structures (Disney, 1999).Abbreviations of abdominal tergites and sternites appear as T and S respectively, with figures indicating the number of an abdominal segment.Wing terminology follows Disney (1994).
Material studied is kept in the following collections: Zoo logical Museum, Cambridge, UK -CMZ, Zoological Institute, St. Petersburg -ZIN, Zoological Museum of Moscow Univer sity -ZMMU, Institute of Biology and Pedology, Vladivostok -IBP, Museum National d'Histoire Naturelle, Paris -MNHN, Los Angeles County Museum, USA -LACM, Zoologisches Forschungsinstitut und Museum Alexander Koenig, Bonn -ZFMK, Zoological Museum of University of Helsinki -ZMUH, collection of the first author -MBM, collection of the second author -MVM.TAXONOMY Gymnophora amurensis sp.n.Diagnosis.Strong mediolaterals absent.Notopleural ridge pale brown.Costa without abrupt thickening before Ri.Posterior margin of left side of epandrium without lobes or incisions.Left side of hypandrium with small process.

Description
Male.Body length 3.55 mm.Third antennal segment brown.Palpi brown, slightly broadened, with 3 apical and ventro-apical bristles, most apical of which is longest and exceeds maximum palpus breadth.Additionally, there are numerous ventral and lateroventral hair-like bristles.Mediolaterals similar to adjacent hairs.Notopleural ridge pale brown.Legs yellowish brown.Wing length 3.45 mm.Costal index 0.52.Costal ratios 7:1.05:1.Costa just slightly gradually thickened before R1.Axillary ridge with 2 bristles.Halteres pale yellow.Abdominal venter bare, except for segment 6, where small hairs form a transverse patch at middle of posterior margin; few hairs just below T6.Tergites with scattered small hairs, which are remarkably longer in posterior half of T6.Posterior margin of left side of epandrium oblique, with bristles arranged in row on prominent ridge (Fig. 4).Right side of epandrium with knob-like posteroventral lobe bearing bristles and curly hairs (Fig. 5).Left side of hypandrium with small scoop-like process (Fig. 6), right side of hypandrium simple.Ring of basiphallus somewhat elon gated (Fig. 7).Cerci moderately long.Hypoproct some what elongated.

Comments.
The greatly swollen process of the left side of the hypandrium is the most distinctive feature of the males of this species.However, we found that rarely this process is less swollen and may be easily confused with that of G. perpropinqua sp.n.In this case one should refer to the ventral lobe of the left side of the epandrium, which is much smaller than in G. perpropinqua sp.n.Females of arcuata are very similar to those of G.perpropinqua.Meigen (1830) described G. arcuata based on two females, but did not designate the holotype.To clarify the identity of this species, we have re-examined the syntypes and designated the lectotype and paratype.The type locality cannot be determined from the label data, although Macquart (1835), who erected the genus Gymnophora with G. arcuata as the type species, noted that this species is distributed in the northern France and northern Germany.
Gymnophora nigripennis Schmitz, 1926 (Figs 21,43,55,56,66,67) Diagnosis.Mediolaterals at most just slightly differ from adjacent hairs.Notopleural ridge dark.Costa gradu ally thickened before R1 .Posterior margin of left side of epandrium oblique and has small elaboration.Left side of hypandrium without process.Male cerci short.Females with abdominal T4 absent.T3 and T5 developed but obviously less than T2 or T6, sometimes reduced to stripe or small patches or developed as semicircular sclerites.T7 narrow wedge-shaped, T8 elongate triangular to pen tagonal.Abdominal venter with single apical sclerite, Comments.The recognition of this species is probably the most troublesome in the genus.Females of this spe cies demonstrate wide variation of the shape of their tergite 8 (Figs 55, 56) and tergites 3 and 5.The female from the northern Maritime Territory seems to be the closest to European specimens, as evidenced by the shape of its abdominal tergites, the shape of the internal sclerotised ring, which is not bent, and the straight hairs between the setae on the apical sclerite of the abdomen.Other speci mens from the Far East and China collected by Licent show other states of these characters.Their T5 developed as a semicircular sclerite (except for the specimen from Kamchatka, whose T5 is greatly reduced), the internal sclerotised ring is more or less bent, and the hairs on the apical sclerite is not straight but somewhat curly (Fig. 67).Chinese specimen collected by Przewalsky has the internal sclerotised ring being not bent and straight hairs on the apical sclerite, besides the semicircular T5.How ever, at the present state of knowledge all these differ ences seem to be insufficient to put these females as a separate species now, especially without a confident asso ciation with males.Brown (1988) reported some other unidentified females of G. nigripennis-subgroup from Japan, and female of G. nepalensis is still unrecognised (Brown, 1988).On balance, we decided to keep these doubtful specimens under the name of G. nigripennis, but the reader should bear in mind that they may in fact belong to other species.
The female from the Kirov Region has been found to be filled with fungal hyphae that penetrate the whole body including the head and legs.This should be of particular interest, since this specimen was caught alive.Gymnophora pararcuata Brown, 1988 (Figs 22-24, 44, 57) Diagnosis.Mediolaterals at most just differ from adja cent hairs.Notopleural ridge pale.Costa with abrupt swelling before Ri enclosing clear spot.Posterior margin of left side of epandrium oblique, bristles situated on wide tubercle.Right side with short hooked process ori ented inwardly and bristles on posteroventral tubercle.Left side of hypandrium with short simple process.Cerci moderately elongated in males, hypoproct short.Female abdomen with T4 and T5 absent, and T3 greatly reduced if any, T7 wedge-shaped with notably concave anterior margin, T8 with asymmetrically developed anterior part.Abdominal venter with paired apical sclerites.Sclerotised abdominal glands absent.
Distribution.Russian Far East, Japan.
Gymnophoraperpropinqua sp.n. (Figs 25,26,45,58,68) Diagnosis.Mediolaterals differ from adjacent hairs, but clearly weaker than bristles on vertex.Notopleural ridge pale.Costa with abrupt thickening that encloses clear spot.Left side of epandrium with well developed ventral lobe.Left side of hypandrium with long process, which is just slightly swollen at mid-length.Female abdomen with T4 and T5 absent and T3 somewhat reduced, T7 wedge shaped, T8 broad watchglass-shaped, both T7 and T8 similar to those of G. arcuata.Abdominal venter with paired apical sclerites, which are rounded and with 21-27 setae that are not densely arranged along outer margin.Sclerotised abdominal glands absent.
Male.Abdominal venter bare, with exception of last segment, which bears extremely short scattered hairs at rear.Tergites with dispersed short hairs.Hypopygium similar to that of G. arcuata.However, epandrium with strongly developed ventral lobe (Fig. 25), and hypandrial process only slightly swollen at mid-length (Fig. 26).Cerci moderately long.Hypoproct short.
Comments.This new species seems to be very closely related to G. arcuata.Even the aedeagal complexes are very similar in these species, although they usually differ in other closely related species.The most remarkable fea ture that distinguishes G. perpropinqua from G. arcuata is the process of the left hypandrial lobe, which is not swollen as much as the process of G. arcuata.Another character is the well developed ventral lobe of the left side of the epandrium.In females, the shape of T7 and T8 vary greatly in both species, and therefore they cannot be used as reliable characters for separation of these species.The only more or less reliable feature is the shape of the apical sclerites, and setation pattern of these sclerites.In the new species these sclerites are somewhat smaller, more rounded and have fewer setae, which are not arranged so densely along the outer margin as those in G. arcuata.Cerci are relatively shorter in G. perpropinqua.Differences between these two species are rather faint in the wing venation.However, the mean costal index is somewhat greater in specimens of G. arcuata that are to hand, and notably greater if one takes into account the figures obtained for European specimens by Brown (1987).
Diagnosis.Mediolaterals notably strong, although they are obviously weaker than those on vertex.Notopleural ridge dark.Costa without abrupt thickening before R1.Posterior margin of left side of epandrium without abrupt excavation or elaboration, process of right side of epan- drium with notch near its tip when viewed from below, and with bristles arranged in row.Left side of hypandrium without process.Cerci short.Female abdomen with T3-5 reduced, T7 approx.as long as broad, with numerous setae, T8 narrow wedge-shaped, with concave sides.Abdominal glands weakly sclerotised.Abdominal venter with paired apical sclerites, which are small and somewhat rounded.
Comments.This species was described nearly simulta neously from Germany and Russian Far East.The shape of both left and right sides of the epandrium and the pat tern of setation support the newly proposed synonymy.Schmitz, 1920 (Figs 29, 30, 60) Diagnosis.In males, mediolaterals clearly differ from adjacent hairs, but at least 2 times weaker than bristles on vertex, mediolaterals absent in females.Notopleural ridge dark.Costa gradually thickened before R1 .Left side of epandrium with excavated posterior margin, with three to four bristles, and with small triangle elaboration on inner surface.Left side of hypandrium without process.Female abdomen with T4 absent and T3 reduced, T7 long, nar row, triangular, T8 pentagonal.Paired sclerotised glands absent, apical sclerite single.
Etymology.From Latin victoria "victory", to commemorate the year of the victory in the World War II, when one of the paratypes was caught.
Male.Abdominal tergites with scarce short hairs, abdominal venter bare, with exception of last segment, which bears short hairs at rare.Left side of epandrium with straight posterior margin, with broad triangle ventral process bearing poorly distinct tubercle (Fig. 34).Right side of epandrium similar to G. palmula (see Brown, 1998).Hypandrium nearly symmetrical from below.Dis tiphallus long, well sclerotised, foot-like, with obtuse dents along its posterior margin (Fig. 35).Cerci and hypoproct elongate.
Distribution.Middle Asia.48), segment 7 hairy, with hairs being remarkably longer along posterior margin.S7 not developed.T8 generally rectangular, with strongly excavated anterior margin and slightly concave lateral and posterior margins, with numerous setae, which are somewhat longer on postero lateral corners (Fig. 62).Apical sclerites unusually wide and elongate, with short curly hairs arranged along poste rior margin (Fig. 70).Cerci abruptly narrowed at mid length (Fig. 71).Abdominal glands small and poorly sclerotised although clearly visible; gland's opening between segments 5 and 6 distinct and bordered anteri orly with shagreened area.

Diagnosis.
Mediolaterals distinctive but remarkably smaller than bristles on vertex.Notopleural ridge dark.Costa with abrupt thickening before R1 and encloses clear spot.Left side of epandrium with irregular posterior margin and bristles concentrated in the lower part.Left side of hypandrium without process.Inner left arm of aedeagus with five to six peaks, which are clearly visible on prepared hypopygium.Female abdomen with T3 reduced, T4 and T5 absent, abdominal glands sclerotised and clearly visible.Abdominal venter with paired apical sclerites.
Strong mediolaterals absent.Notopleural ridge pale.Costa with abrupt swelling and with clear spot.Left side of epandrium with oblique posterior margin and patch of short bristles.Left side of hypandrium with elon gate process.Redescription Body length 3.6 mm.Palpi dark with paler stem.Mediolaterals indistinct from other hairs.Notopleural ridge pale.Legs yellowish.Wing length 3.1 mm (Fig.