KEY
TO SWEDISH GENERA OF DOLICHOPODIDAE
by
I.Ya. Grichanov
Igor
Grichanov, All-Russian Institute of Plant Protection, Podbelskogo 3, St.
Petersburg, Pushkin, Russia.E-mail: grichanov@hotbox.ru
Last
updated: 27 April 2003
Foreword
Below
are working materials that will be corrected during the 2003, supplemented
with illustrations and published as separate book. The only goal of this
publication is to collect comments and recommendations to improve the tables.
To find species keys, please, click the name of a genus.
The
Dolichopodidae fauna of the world is very large, with approximately 6500
described species and 200 genera (Grichanov, 1999). These mostly predatory
flies are distributed throughout the world including the tropics and high-latitude
islands and territories. In Sweden adults and larvae of almost all species
of long-legged flies are predators inhabiting moist substrata. Small-sized
species may be saprophages in the larval stage. Species of only one genus
(Thrypticus) are known to be phytophages living inside stems of
cereal grasses. Most of the numerous species of the cosmopolitan genus
Medetera
are associated with tree trunks, especially in boreal forests, where their
larvae are predacious mainly on bark-beetles (Coleoptera).
Swedish Dolichopodidae
Beginning
from Carolus Linnaeus, the Swedish scientists of XVIII–XIX century held
leading position in describing European and World dipterofauna. Zetterstedt,
Fallén, Roth, Wahlberg, Stenhammar, Schiner and some others made an important
contribution to the study of Dolichopodidae, and the country had become
one of the best-studied regions of comparable area in the world. Wahlgren
(1912) and Ringdahl (1928) summarised the known data about the Swedish
fauna of the family. Nevertheless, there were no published keys to genera
and species of Swedish Dolichopodidae since the work of Wahlgren (1912)
that included 192 species.
Now
334 species and 32 genera are known in Sweden, belonging to the following
nine subfamilies: Achalcinae, Diaphorinae, Dolichopodinae, Hydrophorinae,
Medeterinae, Neurigoninae, Rhaphiinae, Sciapodinae and Sympycninae. However,
Achalcinae, Neurigoninae, Rhaphiinae and Sciapodinae each contain only
one genus known from Sweden, whereas definition of the other subfamilies
is far from an ideal state. A number of new subfamilies and tribes have
been proposed in the second half of the XX century that means that a revision
of the family systematics on the global scale is needed. So, we do not
think that a key to subfamilies is necessary to give in this work.
Systematic
position of Dolichopodidae
The
family Dolichopodidae belongs to the superfamily Empidoidea, of which Microphoridae
is the closest by morphology and genetics to some subfamilies of long-legged
flies (Chvála, 1983; Collins & Wiegmann, 2002). Empidoidea is the monophyletic
group within so-called “Lower Brachycera” or “Brachycera Orthorrhapha”.
Nevertheless, the extant Diptera are divided usually into two suborders,
Nematocera and Brachycera.
Dolichopodidae
may be distinguished from other Diptera by the following key, based on
d’Assis Fonseca (1978), Chvála (1983), and Papp & Schumann (2000):
1.
Antenna usually long, with scape and pedicel and at least 6 homonomous
flagellomeres, usually longer than head and thorax combined; palpi usually
with 3-5 segments ... Nematocera
–
Antenna shorter; scape and pedicel usually short; the other antennomeres
(usually less than 6 segments) heteronomous, differing from one another;
palpi usually with 1 or 2 segments ... 2
2.
Frontal lunule present (a crescent-shaped area immediately above antennal
sockets) ... Cyclorrhapha-Schizophora
–
No lunule above antennae ... 3
3.
Tarsal empodium in the form of pulvilli, i.e., 3 subequal pads below claws
... ... Stratiomyidae, Xylophagidae, Rhagionidae, Tabanidae
et al.
–
Empodium bristle-like or not discernible, at most at most 2 well-developed
pads below claws ... 4
4.
Basal cells of wing long; vein CuA2 long, reaching wing margin
near A1, or joining A1 close to wing margin (at less
than a quarter of its length back from wing margin) ...
... Asilidae, Syrphidae, Bombyliidae, Therevidae, Pipunculidae et al.
–
Second basal cell short, or even confluent with discal cell; anal cell
short and closed or absent; vein CuA2 absent, reduced, or joining
A1 far from wing margin ... 5
5.
Wing venation without any crossvein in median region of wing ...
... Lonchopteridae, Opetiidae, Phoridae
–
Venation with at least one crossvein in median region of wing ...
6
6.
Wing with both A1 and Sc reaching wing margin, and with posterior
cubital cell (cup) acute at posterior apex; hind tarsus, at least
in male, with one or more basal segments expanded and flattened; arista
(stylus) 3-segmented, terminally situated ... Platypezidae
–
If A1 reaching wing margin, then either Sc incomplete or cup
obtuse or rounded at posterior apex, or cup very small; basal segments
of hind tarsus rarely expanded or flattened ... 7
7.
Vein R4+5 forked; if not, then either prosternum large (fused
with episterna) and metapleura usually bristled, or costa running around
the wing. Antennal scape bristled, at least with a few bristly hairs beneath;
male hypopygium symmetrical and unrotated ... Empididae
–
Vein R4+5 not forked; prosternum in the form of a small sclerite
separated by membrane from the episterna (except Dolichopodidae), costa
ending at wing tip (except Microphoridae) and metapleura always bare; antennal
scape very small, without bristles beneath ... 8
8.
Wing with alula; male hypopygium symmetrical and unrotated, female abdomen
remarkably narrowed apically, ovipositor-like; hind tibiae (or also metatarsi)
laterally compressed and dilated in both sexes ... Atelestidae
–
Alula on wings greatly reduced or not developed; male hypopygium not symmetrical,
rotated towards right or deflexed ... 9
9.
Basal cell moderately large, anal cell differently shaped or even absent;
radial sector originating well beyond humeral crossvein; front tibia with
a sense organ; male hypopygium along longitudinal axis or upturned ...
Hybotidae
–
Basal and anal cells conspicuously small, anal cell usually rounded apically;
radial sector originating opposite humeral crossvein; front tibia without
a sense organ, and male hypopygium deflexed ... 10
10.
Discal cell present, emitting 3 veins to wing margin, veins M1
and M2 arising independently from discal cell; costa running
around the wing; body black or greyish ... Microphoridae
–
Discal cell fused with 2nd basal cell; M1+2 usually
with a curvation or stub-like M2 at middle of its distal part
(M rarely forking apically into M1 and true M2);
costa ending at M1, sometimes at tip of R2+3; body
generally metallic or yellow, rarely greyish ... Dolichopodidae
Morphology
of Dolichopodidae
The
external morphology of the most Dolichopodidae is rather remarkable that
allows easily distinguishing them in a sweeping net even from the closest
Empidoidea and other flies by metallic body and mosquito-like habitus with
long legs (Figs. 1-2). Multiple male colour
and morphological ornaments (male secondary sexual characters or MSSC)
are commonly found on antennae, mouthparts, legs, wings and abdomen in
many Dolichopodidae species in addition to large genital capsule (hypopygium).
This decoration developed more in tropical species marks out long-legged
flies from all other Diptera (Sivinski, 1997).
The
head is more or less hemispherical, at most suboval in front view. The
occiput may be flat, slightly convex or (rarely) concave. The vertex at
the top of the head is usually concave with somewhat projected ocellar
tubercle bearing 3 ocelli. The frons is usually broad, and more or less
decreasing in breadth towards the antennae, or rarely reduced to a small
triangle, and the eyes are contiguous or distinctly convergent above the
antennae (Diaphorus males). Three pairs of bristles could be found
on the top of head: the ocellar bristles raising between ocelli; the verticals
at the upper angle; and the postverticals sitting on posterior slope of
the vertex. There is a row of postocular setae along the whole length of
the hind margin of the eyes, adjacent to more or less dense hairs in the
lower part of head. The eyes are large, suboval, densely covered with microscopical
hairs, but sometimes bare (Medetera). The face may be parallel-sided,
but it is often narrowing downward, sometimes greatly reduced (in Chrysotus
males)
or narrowing above the middle and widening downward (Campsicnemus).
The face is divided by transverse suture into the upper part, epistome,
and the lower part, clypeus. The suture is more or less distinct in Medeterinae
and Hydrophorinae, but it is often inconspicuous in other subfamilies.
The clypeus is usually adjacent to eyes, with straight lower margin, sometimes
convex at apex, distinctly projecting below level of the lower eye-margin
(some species of Dolichopus and Tachytrechus). The face is
usually bare, rarely epistome or clypeus are covered with more or less
distinct hairs or even setae. The genae (jowls) are usually rudimentary,
but their height is important for distinguishing some species of Hydrophorus.
The proboscis is usually short, weakly developed, but strongly elongated
and projected downward in Ortochile and some species of Hercostomus.
The one-jointed maxillary palps are flat, squamiform, suboval, cover proboscis
anteriorly, and bear hairs on outer side and one or several bristles at
apex.
The
antennae are generally inserted at the upper third of head, rarely (in
Diaphorus
males) below the middle, each consists of the 3 segments. They are usually
shorter or a little longer than the head height, in males often longer
than in females. The scape (1st segment) is small, globular,
sometimes with short apicoventral acute projection; the pedicel is laterally
compressed, convex on inner side in majority of species, or having finger-like
inner projection (Syntormon) penetrating inner side of postpedicel.
The postpedicel (3rd segment or 1st flagellomere
in old literature) is laterally compressed, in distal part especially,
usually asymmetrical, subtriangular, rounded, suboval, lancet-like etc.
The antennal stylus (arista) is bisegmented, may be basodorsal, dorsal,
dorsoapical or apical, with the 2nd segment having sometimes
elongated hairs or widened or flattened parts. The scape is bare or covered
with more or less distinct hairs or setae above; the pedicel has usually
complete ring of distal setulae; the postpedicel is covered with microscopic
or comparatively long hairs.
The
thorax has more or less parallelepipedic shape (subrectangular), covex
laterally. Prothorax and metathorax are weakly developed. Metasternum is
not pronounced; metaepimera are distinct. Mesonotum generally has lateral
vestiges of transverse suture, often more or less distinctly flattened
posteriorly in front of scutellum. In most species of the family the mesonotum
has well developed bristles that may be grouped as follows. The acrostichals
are short as a rule, arranged in one or two rows along median axis of mesonotum,
or absent. Usually 6 pairs of strong dorsocentral bristles are present,
with anterior 1-4 pairs being often reduced to hairs. One humeral bristle
is often accompanied with one or several weak setae. 1-2 posthumeral, presutural,
3 supraalar, 1 postalar, 2 notopleural bristles may undergo a certain extent
of reduction. Proepisternum may bear hairs or one or several strong setae.
Metapleura glabrous; pteropleura usually glabrous, sometimes covered with
more or less distinct hairs in front of posterior spiracle. Scutellum bare
above or covered with hairs, bearing 2-4, rarely 6 strong marginal setae.
The
legs are generally long and slender, sometimes more robust; they show very
often sexual dimorphism, being variously shaped and adorned in the male,
often rather peculiar; thus the tarsi (fore, mid or hind) may have one
or more segments dilated or plumed or ornated with hairs, bristles or thorns,
or some segments may be unusually shortened or elongated. Also the tibiae
and femora may have special bristles in the males, and sometimes a fringe
of long hairs below. Moreover the legs, especially the tarsi, are often
longer in the male than in the female. The legs have generally short, sometimes
longer hairs and setulae, and are generally provided with bristles, especially
on the dorsal side of the tibiae. Sometimes the legs are less bristly or
almost bare. The bristles (or setae) are divided into dorsal, ventral,
anterior, posterior, anteroventral, posteroventral, anterodorsal and posterodorsal
ones. The bristles on the hind tibiae are in a few genera continued out
on the basitarsus. The femora have often one or more subapical or basoventral
setae having significance for the taxonomy. The tibiae have also apical
bristles, often small. The fore coxa has as a rule bristles or bristly
hairs on the anterior or outer (external) side towards the apex, and the
hind coxa have generally one, sometimes several, characteristic bristles
on the outside. There are two claws, generally small, two pulvilli and
empodium on the 5th segment of tarsi. In the species of Diaphorus
with the pulvilli on some tarsi enlarged in the male, these tarsi have
no claws.
The
wings are generally long and narrow, being sometimes narrower or broader
in males. They are sometimes wholly or partly darkened or more or less
dark spotted. The venation is rather uniform, and it is characteristic
for the family in its principal formation. The costa (C) usually (with
the exception of
Cryptophleps) reaches to the apex of the median
vein (M1+2). There is sometimes a thickening (stigma) at the
junction of first radial vein (R1) and costa. The subcostal
vein (Sc) is short, either joining with R1 or ending free. R1
reaches C in the basal half of wing. The radial veins (R1, R2+3
and R4+5) are unforked. The vein M1+2 is generally
also unforked, only forked in Sciapus and other (non-Swedish) genera,
and with a tendency towards forking in some other genera. The distal part
of M1+2 (the part behind the posterior cross-vein, or m-cu)
is as a rule more or less curved, or angularly bent; there are all gradations
from a quite rectangular bend, sometimes with small stub-vein M2,
through a smaller, more obtuse or rounded curvature to a quite shallow
and gentle, sometimes scarcely perceptible flexure, and finally the vein
may be quite straight and parallel with R4+5. The position of
m-cu
(closer to the wing base or to the middle of the wing) sometimes has taxonomic
significance. The cubital vein (CuA1) is divided by m-cu
into basal (proximal) and distal (apical) parts, with ratio of the latter
and m-cu being important distinguishing feature. The anal vein (A1+CuA2)
is generally abbreviated or fold-like, not reaching the margin. The anal
lobe larger or smaller, sometimes wanting in males, and the wing then cuneiform.
Alula very small in Swedish species, the margin here generally with somewhat
long hairs. The lower calypter is directed upwards, bearing a fan of long
cilia or bristles.
Abdomen
longer or shorter, sometimes even shorter than thorax (e.g., Hydrophorus);
it is usually more or less narrowed towards the end and thus sometimes
conical. In the female it is generally pointed. The abdominal tergites
are much broader than the sternites, and arched. The 1st tergite
is generally shorter than the following; the 1st sternite is
greatly reduced, at most forming a small chitinisation just in front of
the 2nd. In the male the abdomen has eight segments, then follows
the hypopygium, formed of the ninth segment. Sometimes all segments are
visible, but often some of the pregenital segments are hidden, so that
only five or six segments are visible anterior to the hypopygium. Fifth
and sixth sternites are often membranous and folded up grove-like, so that
a smaller or larger cavity for the reception of the hypopygium is formed.
The 7th segment is generally asymmetrical; it has membranous
sternite and chitinised tergite, forming sometimes well-developed stalk
or peduncle. The eighth tergite is scale-like, often roundish, rarely having
rudiment of sternite at ventral angle, and it lies always on the left side
of the hypoopygium, covering epandrial foramen. The epandrium (ninth tergite)
may vary considerably in size and shape; it is generally somewhat oval,
and more or less elongated, or short and roundish; it is more or less asymmetrical
in basal and ventral halves. On the ventral side it is deeply invaginated,
being opened ventrally and apically (sometimes only apically). The sides
of the cavity are often forming more or less distinct ventral epandrial
lobes bearing epandrial setae. The hypandrium (ninth sternite) is usually
fused ventrally with epandrium to various extent, rarely articulated. The
hypandrium covers partly the aedeagus (penis, phallus, phallosome). Both
hypandrium and aedeagus may bear lateral lobes and be of various shape,
having sometimes key value for distinguishing sister species (e.g., in
Chrysotus
and Medetera). There are two pairs of surstyli at distal apex, specialised
clasping lobes that originate as lateral outgrowths of the epandrium, with
ventral and dorsal arms being often fused to various extent. The unpaired
postgonite is located between surstyli or between cerci; it is often simple
and hidden, sometimes symmetrically or asymmetrically lobated, but may
have quite various shape. The cercus, usually large one-segmented scale-like,
or sometimes filiform lobes, are located at distodorsal apex of epandrium.
They may also be subtriangular, roundish, elongated, forked or of other
shape; they are generally hairy, and the margin is not rarely split into
teeth and has long, more or less curved or flattened setae. Sometimes the
cerci are partly fused basally. The cerci together with the other structures
of hypopygium bear very important taxonomical load, but they are often
not visible without dissection and maceration in alkali, especially when
hypopygium is embedded.
In
the female the abdomen has generally five visible segments, the following
(postabdominal) are more or less tapered and retracted into the preceding
segments, forming a telescoped ovipositor (or oviscapt), but sometimes
all segments are seen. The sclerites of these retractible segments are
often subdivided, reduced, or absent, while the membranous areas are enlarged,
so that the ovipositor is flexible and predominantly membranous. Nevertheless,
females of Thrypticus have strongly sclerotised knife-shaped ovipositor
adapted for piercing plant tissues. The cerci and anus, as well as genital
opening are positioned posteriorly of 8th sternum. Ninth and
tenth tergites are fused, often divided with longitudinal membranous zone
into hemitergites (acanthophorites) bearing usually thick or spine-like
paired dorsal setae. The anal plate is probably homologous with 10th
sternite.
Keys
presented below are compiled on the base of British, French, German and
Russian manuals and keys to species of Dolichopodidae. Some recent European
and Palearctic revisions of small genera or species groups are also used.
Several old species are known by females only and there are some unverified
records of Dolichopodidae from the country, which means that adjustments
to the list should be anticipated. At the same time a few species described
from neighbouring Nordic countries may be found in Sweden as well.
The
keys to Swedish genera and species of Dolichopodidae are compiled for advanced
users. Before using them I would strongly recommend to get acquaintance
with introductory chapters from the “Contributions to a manual of Palaearctic
Diptera”
(Papp & Darvas, 2000) and “Manual
of Nearctic Diptera”
(McAlpine, et al.,
1981-1989). For English readers some introductory notes may be useful (despite
the different terminology) from Lundbeck (1912), Robinson
(1970, 1975), Dyte (1975), d’Assis
Fonseca (1978), Bickel
& Dyte (1989), and Bickel (1992, 1994). A great number of valuable
illustrations together with introductions, keys and species descriptions
in French, German and Russian could be found in Parent
(1938), Lindner (1930-1979), Negrobov & Stackelberg (1969). See also
web-sites: http://www.ifrance.com/Dolicho/
(in French) and http://members.fortunecity.com/grichanov/
(in English) devoted to Dolichopodidae.
KEY
TO GENERA OF DOLICHOPODIDAE
1.
Wing vein M2 present, almost reaching wing margin ... Sciapus
– Vein
M2 absent or stub-like, without fold or indication on membrane
... 2
2.
Costa of wing ending at tip of R2+3; M1+2 weak or
broken near middle of distal part ... 3
– Costa
of wing extending to tip of M1+2; M1+2 never weaker
near middle of distal part ... 4
3.
Male hypopygium usually with strong macrochaetae; acrostichals usually
present ... ... Asyndetus (absent in Sweden)
– Male
hypopygium without strong macrochaetae; acrostichals absent or microscopic;
1.5 ... Cryptophleps kerteszi Lichtwardt
4.
Antennal pedicel, seen on inside face, forming a more or less long thumb-like
projection into postpedicel ... Syntormon
–
Antennal pedicel simple, vaselike, without thumb-like projection ...
5
5.
Acrostichal setae absent ... 6
–
Acrostichals distinct, even though sometimes small ... 15
6.
Face divided into epistome and clypeus by transversal suture, and this
division is distinctly pronounced along width of face (from eye to eye)
... 7
–
Facial suture indistinct or hardly marked at eye margin ... 11
7.
Occiput concave, and head adjacent to thorax; postvertical setae absent;
eyes bare or almost bare ... Medetera
–
Occiput convex, and head not adjacent to thorax; postvertical setae present;
eyes haired ... 8
8.
Face narrow, not wider than ocellar tubercle; hypopygium free; 3.0.Figs.
84, 85 ... Peodes forcipatus Loew
–
Face wide, wider than ocellar tubercle; hypopygium usually sessile ...
9
9.
4 pairs of dorsocentral setae; antennal stylus subapical ... Thinophilus
(part)
–
5-6 pairs of dorsocentral setae; antennal stylus dorsal ... 10
10.
Fore femur and tibia with strong and long ventral spines; male abdomen
behind segment IV with long remarkable appendices ... Scellus
–
Fore femur and tibia without long ventral spines; abdomen behind segment
IV without appendices ... Thinophilus
11.
Hind femur without subapical bristle ... 12
–
Hind femur with subapical bristle ... 13
12.
Hind basitarsus distinctly shorter than 2nd tarsomere; body
mostly black; bristles on head and thorax dark; veins R4+5 and
M1+2 more or less parallel; legs brownish black; 1.75.Fig.
10 ... ... Acropsilus niger (Loew)
–
Hind basitarsus about equal in length to 2nd tarsomere; body
mostly yellow; head and thorax with yellow bristles; R4+5 and
M1+2 convergent ... Xanthochlorus
13.
Face narrow in middle, extending downward ... Campsicnemus
– Face
narrowed more or less gradually downward ... 14
14.
Body light green, metallic shining; head and thorax with yellow bristles
... Chrysotimus
–
Body brown, not shining; head and thorax with dark bristles ... Micromorphus
15.
Acrostichal setae uniseriate at least in anterior part ... 16
–
Acrostichal setae in two regular rows ... 26
16.
Body light green, metallic shining; head and thorax with yellow bristles
... Chrysotimus
–
Different characters ... 17
17.
Antennal stylus apical or subapical; scape with hairs above ... Syntormon(part)
–
Stylus dorsal ... 18
18.
Face divided into epistome and clypeus by transversal suture, and this
division is distinctly pronounced along width of face (from eye to eye)
... 19
–
Facial suture indistinct or hardly marked at eye margin ... 22
19.
Fore femur and tibia with strong spiniform ventral bristles; the bristles
arranged usually in longitudinal rows ... 20
–
Fore femur and tibia without strong spiniform ventral bristles ...
21
20.
Postpedicel with apicoventral incision; proepisternal setae not
developed, rarely 1 seta present; scutellum with 4 setae usually; abdomen
behind segment IV without appendices ... Hydrophorus
–
Postpedicel without apicoventral incision; 3 proepisternal setae; scutellum
with 2 setae; abdomen behind segment IV with long remarkable appendices
... Scellus
21.
Face narrow, not wider than ocellar tubercle; hypopygium globular, free,
with 2 long baculiform projections; posterior crossvein m-cu shorter
than distal part of CuA1; 3.0 (see above) ... Peodes
forcipatus Loew
–
Face wider;
m-cu at least as long as distal part of CuA1;
scutellum with 6 setae of equal length; 6 pairs of dorsocentral setae;
proepisternal setae not developed; 7.0-8.0.Fig.
83 ... ...
Liancalus virens (Scopoli)
22.
Face narrow in middle, extending downward ... Campsicnemus
– Face
narrowed gradually downward or with more or less parallel sides ...
23
23.
4 pairs of dorsocentral setae; antennal stylus lanceolate at apex; 2.0
... ... Telmaturgus tumidulus (Raddatz)
–
At least 5 pairs of dorsocentral setae; stylus not lanceolate at apex ...
24
24.
Occiput concave, and head adjacent to thorax; hypopygium with strong setae;
hind femur without subapical setae; face more or less parallel sided; 2.0
... ... Melanostolus melancholicus (Loew)
–
Occiput convex; hypopygium without strong setae; hind femur with subapical
setae; face narrowed downward ... 25
25.
Five pairs of strong dorsocentral bristles; mid femur with ventral bristles
in basal part; wing costa with long and thick stigma beyond R1 ...
Teuchophorus
– Six
pairs of dorsocentral bristles; mid femur without ventral bristles; wing
costa without stigma beyond R1 ... Sympycnus
26.
Scape with hairs above ... 27
– Scape
bare above ... 33
27.
Occiput concave, and head adjacent to thorax; hypopygium concealed; epandrial
lobe and cercus small; hind coxa with vertical row of fine setae; hind
femur without subapical seta ... Argyra
–
Occiput convex; hypopygium free; cercus big and also free; hind coxa with
one seta; hind femur with subapical seta ... 28
28.
Antennal stylus long pubescent; with hairs approximately 1.5 times longer
than basal diameter of stylus; notopleuron having strongly pronounced purple
spot; male cercus elongate-triangular, strongly incised along ventral margin
... Hercostomus (Poecilobothrus)
–
Antennal stylus bare, rarely pubescent; notopleuron usually without purple
spot; cercus various ... 29
29.
Hind basitarsus with distinct bristle above ... Dolichopus
– Hind
basitarsus without bristles above ... 30
30.
Proboscis long and narrow, at least 1.5 times longer than height of head;
palpus long and narrow, adjacent to proboscis; veins R1, R2+3
and
R4+5 positioned close to anterior wing margin; 3.0. Fig.
138 ... Ortochile nigrocoerulea Latreille
–
Proboscis thick and short, not longer than height of head; palpus short,
or if long, then comparatively broad ... 31
31.
Several strong anterodorsal setae in apical half of the hind femur in addition
to the true anterior subapical seta; face narrowed under antennae and somewhat
widened towards clypeus; wing vein M1+2 usually with gentle
curvation before the middle of distal part, then running towards R4+5 and
reaching costa far before the tip of wing; arista short and bare; first
flagellomere usually short and suboval ... Tachytrechus
– Hind
femur with one true anterior subapical seta; face regularly narrowed towards
clypeus or parallel-sided; wing vein M1+2 either with curvation
beyond the middle of distal part or M1+2 reaching costa near
the tip of wing; arista often pubescent; first flagellomere usually subtriangular,
asymmetric ... 32
32.
Hypopygium very long, with long peduncle (7th segment); surstylus
long, clavate, with long cilia at apex; abdomen long; legs long and thin
... Sybistroma
–
Hypopygium moderately long, sessile or having short peduncle; surstylus
usually short; abdomen and legs ordinary ... Hercostomus
33.
Face divided into epistome and clypeus by transversal suture, and this
division is distinctly pronounced along width of face (from eye to eye);
posterior slope of mesonotum distinctly flattened between dorsocentral
setae ... 34
–
Facial suture indistinct or hardly marked at eye margin ... 35
34.
R4+5 and M1+2 convergent, at most subparallel at
apex; thorax densely pollinose; male surstylus and cercus usually not deflexed
dorsad ... Medetera
– R4+5
and M1+2 parallel to apex; thorax shining green; male surstylus
strongly deflexed dorsad, usually lying conformably with similarly deflexed,
oblong-shaped cerci ... Thrypticus
35.
Hind coxa on outer side without seta, or with vertical row of setiform
hairs, or covered with dense hairs ... 36
–
Hind coxa with at least one strong external seta ... 37
36.
Occiput concave, and head adjacent to thorax; hind coxa with vertical row
of fine setae; antennal stylus subapical ... Argyra
(Leucostola)
–
Occiput convex; hind coxa on outer side covered with dense hairs; antennal
stylus apical ... Rhaphium (part)
37.
Hind femur without true subapical seta ... 38
–
Hind femur with true subapical seta ... 43
38.
Male face broad, eyes contiguous or distinctly convergent above antennae;
mid tibia often with ventral seta; hypopygium with strong macrochetae ...
Diaphorus
–
Male frons broad, eyes distinctly convergent or contiguous below antennae;
mid tibia rarely with ventral seta; hypopygium rarely with strong macrochetae
... 39
39.
Eyes strongly convergent or contiguous below antennae ... Chrysotus
–
Eyes distinctly separated below antennae, or slightly convergent towards
palpi ... 40
40.
Antennal stylus dorsal ... 41
–
Stylus apical or strictly subapical ... 42
41.
Hypopygium free; legs long and thin; body mostly yellow ... Neurigona
–
Hypopygium sessile; legs of ordinary length and width; body metallic green;
2.0 ... ... Melanostolus melancholicus(Loew)
42.
Hypopygium pedunculate; hind basitarsus at most half as long as next segment
of same tarsus ... Systenus
–
Hypopygium sessile; hind basitarsus barely shorter than next segment of
same tarsus ... ... Rhaphium
(part)
43.
Antennal stylus apical ... 44
–
Stylus dorsal ... 45
44.
R4+5 and M1+2 slightly to distinctly divergent; A2
absent; body without metallic shine or weakly shining ... Achalcus
–
R4+5 and M1+2 not divergent; A2 present;
body bronze green, metallic shining ... Rhaphium
(part)
45.
Four pairs of dorsocentral setae; mesonotum with two large velvety black
lateral spots; 2.0 ... Lamprochromus bifasciatus (Macquart)
–
Six pairs of dorsocentral setae; mesonotum without velvety black lateral
spots ... Sympycnus
Females
1.
Wing vein M2 present, almost reaching wing margin ... Sciapus
– Vein
M2 absent or stub-like, without fold or indication on membrane
... 2
2.
Costa of wing ending at tip of R2+3; M1+2 weak or
broken near middle of distal part ... 3
–Costa
of wing extending to tip of M1+2; M1+2 never weaker
near middle of distal part ... 4
3.
Acrostichals usually present ... Asyndetus
– Acrostichals
absent or microscopic ... Cryptophleps
4.
Antennal pedicel, seen on inside face, forming a more or less long thumb-like
projection into postpedicel ... Syntormon
–
Antennal pedicel simple, vaselike, without thumb-like projection ...
5
5.
Acrostichal setae absent ... 6
–
Acrostichals distinct, even though sometimes small ... 16
6.
Hind femur without subapical bristle ... 7
–
Hind femur with subapical bristle ... 9
7.
Hind basitarsus about two fifth length of 2nd tarsomere; body
mostly black; legs brownish black; 1.75 ... Acropsilus niger (Loew)
–
Hind basitarsus about equal in length to 2nd tarsomere ...
8
8.
R4+5 and M1+2 distinctly convergent; body mostly
yellow; head and thorax with yellow bristles ... Xanthochlorus
–
R4+5 and M1+2 more or less parallel or barely convergent;
body not yellow; head and thorax with dark bristles ... Thinophilus
9.
Occiput concave, and head adjacent to thorax; R4+5 and M1+2
straight, slightly convergent apicad; usually 3 dorsocentral setae; eyes
bare ... Medetera
–
Occiput convex; eyes haired; 4-5 or more dorsocentral setae; R4+5
and M1+2 more or less parallel ... 10
10.
4-5 dorsocentral setae ... 11
–
At least 6 dorsocentral setae ... 14
11.
Face narrow in middle, extending downward ... Campsicnemus
– Face
narrowed regularly downward or parallel-sided ... 12
12.
Head and thorax with yellow bristles; mesonotum light metallic green, shining;
abdomen mostly or entirely yellow ... Chrysotimus
–
Head and thorax with dark bristles; mesonotum and abdomen dark metallic
green ... 13
13.
Face divided into epistome and clypeus by transversal suture; wing with
two brown spots ... Thinophilus
(part)
–
Facial suture indistinct; wing hyaline, without spots ... Micromorphus
14.
Fore femur with row of strong and long ventral spines ... Scellus
–
Fore femur without strong ventral spines ... 15
15.
Three proepisternal setae; R4+5 and M1+2 curved,
more or less convergent apicad ... Thinophilus
–
One proepisternal setae; R4+5 and M1+2 straight,
more or less parallel ... Peodes
16.
Acrostichal setae uniseriate at least in anterior part ... 17
–
Acrostichal setae in two regular rows ... 26
17.
Body light green, metallic shining; abdomen mat yellow, with black apex
... Chrysotimus
–
Different characters ... 18
16.
Antennal stylus apical or strictly subapical; scape with hairs above; hind
femur with one subapical bristle ... Syntormon(part)
–
Stylus dorsal ... 17
17.
Face divided into epistome and clypeus by transversal suture, and this
division is distinctly pronounced along width of face (from eye to eye);
m-cu
usually equal to or longer than distal part of CuA1 ...
18
–
Facial suture indistinct or hardly marked at eye margin; m-cu usually
shorter than distal part of CuA1 ... 21
18.
Fore femur and tibia armed with more or less developed ventral setae or
spines ... 19
–
Fore legs not armed ... 20
19.
Postpedicel with apicoventral incision; proepisternal setae not
developed, rarely 1 seta present; scutellum with 4 setae usually, rarely
with 2 setae; fore tibia with short ventral setae or spicules ... Hydrophorus
–
Postpedicel without apicoventral incision; 3 proepisternal setae; scutellum
with 2 setae; fore femur and tibia with long ventral setae ... Scellus
20.
Posterior crossvein m-cu distinctly shorter than distal part of
CuA1; smaller flies ... Peodes
–
m-cu
at
least as long as distal part of CuA1, oblique; scutellum with
6 setae of equal length; larger flies ... Liancalus virens(Scopoli)
21.
Hind femur without true subapical seta ... 22
–
Hind femur with true subapical seta ... 23
22.
Occiput convex; clypeus strongly convex; antennal stylus long pubescent
... ... Telmaturgus tumidulus (Raddatz)
–
Occiput concave, and head adjacent to thorax; clypeus not convex; stylus
almost bare ... Melanostolus melancholicus(Loew)
23.
Scape with hairs above ... Syntormon(part)
– Scape
bare above ... 24
24.
Six pairs of dorsocentral setae ... Sympycnus
–
Four pairs of dorsocentral setae ... 25
25.
Face narrowed gradually downward; abdomen more or less cylindrical ...
Teuchophorus
–
Face narrow in middle, extending downward; abdomen flattened dorsoventrally
... Campsicnemus
26.
Scape with hairs above ... 27
– Scape
bare above ... 32
27.
Occiput concave, and head adjacent to thorax; hind coxa with vertical row
of fine setae; hind femur without subapical seta ... Argyra
–
Occiput convex; hind coxa with one seta; hind femur with subapical seta
... 28
28.
Antennal stylus long pubescent; with hairs approximately 1.5 times longer
than basal diameter of stylus; notopleuron having strongly pronounced purple
spot ... ... Hercostomus(Poecilobothrus)
–
Antennal stylus bare, rarely pubescent; notopleuron usually without purple
spot ... 29
29.
Hind basitarsus with distinct bristle above ... Dolichopus
– Hind
basitarsus without bristles above ... 30
30.
Proboscis long and narrow, at least 1.5 times longer than height of head;
palpus long and narrow, adjacent to proboscis ... Ortochile nigrocoerulea
Latreille
–
Proboscis thick and short, not longer than height of head; palpus short,
or if long, then comparatively broad ... 31
31.
Several strong anterodorsal setae in apical half of the hind femur in addition
to the true anterior subapical seta; face narrowed under antennae and somewhat
widened towards clypeus; wing vein M1+2 usually with gentle
curvation before the middle of distal part, then running towards R4+5
and reaching costa far before the tip of wing; stylus short and bare; postpedicel
usually short and suboval ... Tachytrechus
