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.