Madagascar
Igor Ya. GRICHANOV
Grichanov, I.Ya. Two new species of Urodolichus Lamb (Diptera:
Dolichopodidae) from Madagascar
U. lambi and U. ninae spp. n. from Madagascar are described. A
catalogue and key to 6 known species of Urodolichus are given.
I.Ya. Grichanov, All-Russian Institute of Plant Protection,
Podbelskogo 3, St.Petersburg-Pushkin, 189620, Russia.
Key words: Diptera, Dolichopodidae, Urodolichus, Madagascar.
Introduction
The genus Urodolichus was described by Lamb (1922) for three new
species from Seychelles within the subfamily Dolichopodinae, but the
author mentioned some characters common with the genus
Porphyrops Meigen (considered now as synonym of Argyra Macquart,
though many species of Porphyrops were transferred to Rhaphium
Meigen). There have been no any additional records for those species.
Hollis (1964) described Ounyana gen. nov. for O. keiseri Hollis from
Sri Lanka, belonging the new genus to the subfamily Rhaphiinae. The
author was uncertain whether Ounyana should be placed in the
Diaphorinae or Rhaphiinae and consigned it to the latter subfamily by
virtue of its similarity to the South American genus Ionthadophris Van
Duzee (now synonym of Somillus Brethes). Robinson (1970) included
Ionthadophris into Diaphorinae. Dyte (1975) correctly placed Ounyana
in synonymy with the genus Urodolichus, leaving the genus within
Rhaphiinae (Dyte, 1980). In fact, the genus should be referred to
Diaphorinae despite the pedunculate hypopygium unusual for the
subfamily, forming the tribe Argyrini together with Argyra, Somillus,
Dactylonotus Parent, Falbouria Dyte, Keirosoma Van Duzee and
Pseudargyra Van Duzee. The world fauna of the subfamily Diaphorinae
numbers about 20 genera and subgenera united in two tribes, Argyrini
and Diaphorini. Limits of the subfamily are not yet defined well, and
many genera traveled to or from Diaphorinae, whereas others changed
their generic status.
Treating unidentified material from the collection of the Royal
Institute for Natural Sciences [RINS] (Brussels), I found two new
species of the genus Urodolichus from Madagascar. In this paper
descriptions for these species, catalogue and key to species of the
genus are given.
Most part of the material collected from Madagascar is kept in 70%
alcohol inside glass tubes and cans. In addition, one specimen of each
species is also placed after alkalisation into glycerol and mounted on
pin in sealed plastic container.
Holotypes and paratypes of the new species are deposited in the Royal
Institute for Natural Sciences [RINS] (Brussels).
List of known species of Urodolichus Lamb
Urodolichus Lamb, 1922:394. Type-species: Urodolichus porphyropoides
Lamb, 1922, by original designation.
=Ounyana Hollis, 1964:228. Type-species: Ounyana keiseri Hollis, 1964,
by monotypy.
caudatus Lamb, 1922 : 397. Seychelles.
gracilis Lamb, 1922:398. Seychelles.
keiseri Hollis, 1964: 228 (Ounyana). Sri Lanka.
lambi sp. n. Madagascar.
ninae sp. n. Madagascar.
porphyropoides Lamb, 1922:394. Seychelles.
Urodolichus lambi sp. n. (Fig. 1)
Holotype [in alcohol]. Male. Madagascar: 25 km W. Morarano-chrome,
XI.1991, foret, bac jaune, A. Pauly.
Paratypes [mostly in alcohol, one male in glycerol]: 1 female, same
label. 5 males, 1 female, Madagascar: Tam, Morarano-chrome, X.1991, A.
Pauly col. 18 males, 9 females, Madagascar: Tam, Manakambahiny Atn.,
17-23.III.1991, A. Pauly, foret.
Description. Male. Frons small, as high as wide, metallic blue green.
Face of the same colour. Upper margin of frons slightly concave, with
somewhat prominent ocellar tubercle. A strong vertical seta bending
forward just at the upper angle of head near the eye margin, arising
from a small tubercle. A weaker postvertical seta positioned on back
slope slightly lower than upper head margin. Occiput concave. Eyes
distinctly haired along entire surface. Head practically holoptic.
Face as a small triangle below antennae and very thin line slightly
widened at clypeus. Upper postocular setae short, black, uniserial.
Ventral postcranium covered with long fine brownish setae. Palpus
brown, oval, small, with black hairs, as long as palpus. Proboscis
brown-black with short hairs; 6 symmetrically positioned
pseudotracheae. A triangular structure below clypeus present with
pointed apex and one pair of lateral spine-like process. Antenna
short, black, with simple joints. Scape bare. Pedicel with a fan of
mostly dorsal hairs, which longer than 1st flagellomere. Pedicel also
with short lateral lobes covering base of 1st flagellomere in the
middle of both sides. 1st flagellomere rounded, asymmetric, slightly
higher than long, with distinct apicoventral obtuse apex and dorsal
arista. Arista simple, with sparse short hairs. Length ratio of scape
to pedicel to first flagellomere to arista, 5 : 7 : 8 : 55.
Thorax greenish-black. Prothorax and propleura with numerous black
setae and hairs. Mesonotum with two rows of acrostichals and 5 pairs
of dorsocentral setae (mostly broken). Scutellum with one pair of
strong setae, one pair of fine lateral setae, one third or half as
long as major setae, and 2-3 pairs of median marginal hairs.
Legs usually black, sometimes partly brown. Fore coxa with numerous
black anterior setae and hairs, 2/3 as long as coxa; middle coxa with
shorter hairs; hind coxa with single external seta at base. All femora
with double ventral row of cilia along entire length, twice longer
than femur's diameter; anterior subapical setae indistinct. Fore tibia
with 2--3 short apical setae only. Fore basitarsus with simple
setulae. 2nd to 5th tarsomeres shortened; 5th tarsomere slightly
flattened, with several elongate hairs, one pair of claws, simple
empodium and small pulvilli. Length ratio of fore femora to tibia to
tarsus (segments from first to fifth), 67 : 62 : 30 : 6 : 7 : 6 : 7.
Middle tibia with 2 anterodorsal, 2 posterodorsal, 2--3 ventral and
2--3 apical setae. Middle tarsus simple. Length ratio of middle femora
to tibia to tarsus (segments from first to fifth), 75 : 83 : 45 : 16 :
11 : 6 : 7. Hind tibia with 2 anterodorsal, 2 posterodorsal, 2--3
apical setae and posteroventral row of elongate setulae, nearly as
long as tibia diameter. Hind tarsus simple. Length ratio of hind
femora to tibia to tarsus (segments from first to fifth), 95 : 110 :
20 : 30 : 16 : 8 : 10.
Wing oval, smoky, brownish anteriorly in basal half; 1st radial cell
entirely brown; veins black. Sc reaching to R1 at the middle of the
latter. R1 nearly half as long as wing. Venation similar to this in U.
porphyropoides (Lamb, 1922). Ratio of part of costa between R2+3 and
R4+5 to this between R4+5 and M1+2, 28 : 15. R2+3 nearly straight.
R4+5 with wide arc in apical half. M1+2 with strong bosse at basal 2/5
of apical part, parallel to R4+5 in apical 1/4 of wing; m-cu straight,
positioned behind the middle of wing's longitudinal axis. Ratio of
cross-vein m-cu to apical part of CuA1, 18 : 46. Anal vein weak,
not reaching to wing margin; anal lobe developed; alula pronounced;
anal angle acute. Lower calypter brown, with black setae. Halter
light-brown, with rounded knob having ventral comb of short setulae at
base.
Abdomen black-brown, with bluish tinge, short black setae and hairs,
several long basoventral hairs. Six full segments of abdomen
developed. All sternites simple. Postabdomen brown. 7th segment thin
and long, as long as 6th tergite, attached to the latter
apicoventrally. 7th tergite with short hairs. 8th segment with short
hairs, 1/3 as long as 7th, attached to the tip of the 7th, embracing
epandrium left-basolaterally. Epandrium oval, half as long as 7th
segment. Cercus brown, budlike, when measured along dorsal margin,
slightly longer than epandrium, densely covered with short cilia,
which very short at pointed apex. Three pairs of surstyli long and
thin, almost straight; the longest surstylus bearing strong apical
spine. Epandrial lobe as long as surstylus, slightly sinuate.
Hypandrium midventral, short.
Female. Similar to male except lacking male secondary sexual
characters, otherwise as follows: Face narrowed towards palpi. Height
ratio of frons, epistome and clypeus, 15 : 25 : 10. Width ratio of
epistome under antennae to this at clypeus, 13 : 5. Eyes, pedicel and
palpi with shorter hairs than in male. Femora with ventral cilia, half
as long as femur's diameter. Hind tibia with short setulae. Abdomen
with 5 visible segments. 9th hemitergite with a transverse row of 5
short acanthophorites. Cercus short, lamellate, as long as sclerotized
part of 9th hemitergite, with microscopic hairs. Anal plate with
several pairs of long light cilia.
Length: body 3.8--4.3 mm, male postabdomen 1.1 mm; antenna 0.9 mm;
wing-length 3.95 mm; wing-width 1.4 mm.
Distribution. Madagascar.
Diagnosis. Having short cercus, the new species is close to U.
gracilis, differing in black antenna, mostly black legs; all femora
with double row of stout ventral setae; epandrium half as long as 7th
segment.
Urodolichus ninae sp. n. (Fig. 2)
Holotype [in alcohol]. Male. Madagascar: 25 km W. Morarano-chrome,
XI.1991, foret, bac jaune, A. Pauly.
Paratypes [mostly in alcohol, one male in glycerol]: 3 males, same
label. 3 males, Madagascar: Tam, Morarano-chrome, X.1991, A. Pauly
col.
Description. Male. Similar to U. lambi except as noted. Palpus with
short hairs, only several cilia nearly as long as palpus. Length ratio
of scape to pedicel to first flagellomere to arista, 4 : 5 : 6 : 50.
Fore coxa with numerous black anterior setae and hairs, half as long
as coxa. All femora with double ventral row of cilia along entire
length, not longer or slightly longer than femur's diameter. Length
ratio of fore femora to tibia to tarsus (segments from first to
fifth), 65 : 61 : 25 : 5 : 5 : 5 : 6. Middle tibia with 2
anterodorsal, 2 posterodorsal, 1--2 ventral and 2--3 apical setae.
Length ratio of middle femora to tibia to tarsus (segments from first
to fifth), 75 : 77 : 42 : 15 : 10 : 6 : 8. Hind tibia with 2
anterodorsal, 2 posterodorsal, 2--3 apical setae and several elongate
posteroventral setulae, nearly as long as tibia diameter. Length ratio
of hind femora to tibia to tarsus (segments from first to fifth), 85 :
105 : 20 : 26 : 15 : 8 : 8.
Wing. Ratio of part of costa between R2+3 and R4+5 to this between
R4+5 and M1+2, 28 : 15. Ratio of cross-vein m-cu to to apical part of
CuA1, 17 : 39.
Abdomen. 7th segment thin and long, slightly longer than 6th tergite.
Epandrium oval, 1/2 as long as 7th segment. Cercus 2.5 times longer
than epandrium, swollen at base, narrow, lamellate, with narrowed
apex, large internal tooth at middle of narrow part, covered with
short cilia along entire length. slightly longer than epandrium. Three
pairs of surstyli long and thin, almost straight; the longest
surstylus bearing strong apical spine. Epandrial lobes as long as
surstylus, slightly sinuate. Hypandrium midventral, short.
Female unknown.
Length: body 3.7--3.9 mm, male postabdomen 1.3 mm; antenna 0.8 mm;
wing-length 2.9--3.2 mm; wing-width 1.3 mm.
Distribution. Madagascar.
Diagnosis. U. ninae sp.n. differs from known species in bare fore
tibia; apical part of CuA1 2 times longer than m-cu; cercus swollen
at base, with large midventral tooth. In addition, the new species
differs from U. porphyropoides in simple fore basitarsus, from U.
caudatus in strongly curved wing
vein M1+2.
Key to species of Urodolichus Lamb (males)
1. Cercus twice or thrice longer than epandrium ............. 2
- Cercus not longer or slightly longer than epandrium ............. 5
2. Fore tibia bare; hind tibia with 2 antero- and 6 posterodorsal
setae ............. U. keiseri Hollis
- Either fore tibia with 1 dorsal and 1 ventral setae or hind tibia
with 4 or 5 setae ............. 3
3. Apical part of CuA1 2 times longer than m-cu; cercus swollen at
base, with large midventral tooth ............. U. ninae sp.n.
- Apical part of CuA1 1.5 times longer than m-cu; cercus with
basoventral lobe, without midventral tooth ............. 4
4. Fore basitarsus with anterior row of regular, almost hooked setae
............. U. porphyropoides Lamb
- Fore basitarsus with ordinary seta row at base ............. U.
caudatus Lamb
5. 1st flagellomere and legs entirely orange; femora with only fine
sparse ciliation; epandrium not shorter than 7th segment .............
U. gracilis Lamb
- Antenna black, legs mostly black; all femora with double row of
stout ventral setae; epandrium half as long as 7th segment
............. U. lambi sp.n.
Acknowledgement
I am sincerely grateful to Dr. Patrick Grootaert for his kindness in
furnishing an opportunity to study the collections of the Royal
Institute for Natural Sciences
(Brussels).
References
Dyte C.E. 1975. Family Dolichopodidae. In M.D. Delfinado & D.E. Hardy
(eds). A Catalog of the Diptera of the Oriental Region. Univ. Haw.
Press, Honolulu, II: 212--258.
Dyte C.E. & Smith K.G. 1980. Family Dolichopodidae. In R.W. Crosskey
(ed.). Catalogue of the Diptera of the Afrotropical Region. Brit. Mus.
(Nat. Hist.), London: 443--463.
Hollis D. 1964. Dolichopodidae (Diptera: Brachycera) from Ceylon,
collected by F. Keiser. Verhandlungen Natuurforschung Gesellschaft,
Basel, 75: 219--230.
Lamb C.G. 1922. The Percy Sladen Trust expedition to the Indian Ocean
in 1905, under the leadership of Mr. J. Stanley Gardiner, M.A. Vol. 7.
N VIII. Diptera: Asilidae, Scenopinidae, Dolichopodidae, Pipunculidae,
and Syrphidae. Transactions of the Linnean Society of London (2,
Zoology), 18: 361--416.
Robinson H. 1970. Family Dolichopodidae. In A Catalogue of the Diptera
of the Americas south of the United States. Sao Paulo: Museu de
Zoologia, Universidade Sao Paulo, 40: 1--92.
Remark under figures
Fig. 1. Urodolichus lambi sp.n., postabdomen, lateral view.
Fig. 2. Urodolichus ninae sp.n., postabdomen, lateral view.
