Bickelia (Diptera: Dolichopodidae), a new genus from Indian Ocean



Grichanov, I.Ya. Bickelia (Diptera: Dolichopodidae),

a new genus from Indian Ocean islands

Bickelia, a new genus of the dolichopodid subfamily

Sciapodinae is described. B. subparallela sp.n., B. parallela

(Macquart) and B. guerini (Parent) are included.

I.Ya. Grichanov, All-Russian Institute of Plant Protection,

Podbelskogo 3, St.Petersburg-Pushkin, 189620, Russia.

Key words: Diptera, Dolichopodidae, Bickelia gen.n., Chagos

Archipelago, Seychelles, Mauritius.

Bickelia gen.n.

Type-species: Bickelia subparallela sp.n., here designated

Description. Male head wider than high; vertex shallow excavated.

Occiput and frons not concave, mat bronze-green, grey pollinose. One

pair of well developed ocellar, postvertical and proclinate vertical

bristles present in both sexes. Upper postocular bristles black, in

one row. Ventral postcranium covered with irregular pale hairs. Eyes

bare, not joined across face. Face and clypeus narrow, female face

wider, with slightly indicated suture, densely silvery pollinose; face

does not come down eyes, clypeus slightly bulging. Cheeks undeveloped.

Palpi and proboscis short. Antennae mostly black, with short articles,

inserted in the upper third of head; scape bare, short, pedicel

sphaeroidal, with short dorsal and ventral subapical setae, without

appendices. First flagellomere as long as high, subtriangle, with

rounded apex, haired. Arista dorsal, simple, with microscopic setulae,

shorter than head height.

Mesonotum metallic green, pleura dark-green or black, grey

pollinose; 1 h, 1 ph, 2 ntpl, 2-3 ia, 1 sa, 1 pa. Five pairs of strong

dorsocentral bristles, with a few hairs in front of them, not sexually

dimorphic; short biseriate acrostichals. Scutellum with two strong

bristles and usually with one pair of marginal hairs. Postnotum

developed. Propleuron with 2 fine ventral setae.

Legs mostly yellow, simple. Male fore and middle coxae with

sparse hairs and with 2-3 fine apical bristles, hind coxae with strong

bristle; female fore coxae usually with additional row of strong

lateral spines. Male fore legs without strong bristles or spines;

female fore femora usually with group of 3-5 strong ventral bristles

in basal third, each bristle arising from a distinct mound-like

pedicel. Middle and hind femora with strong anterior preapical

bristle. Tibiae with developed bristles in both sexes.

Wings elongate, slightly darkened. Veins simple. Costa reaches M

1 before apex; M 1 and R 4+5 almost parallel; M 1 and M 2 slightly

diverged; M 1 not recurved basad, with right angle bend; M 2 straight;

crossvein m-cu straight, placed in the middle of wing. Anal vein

usually reduced. Anal lobe small or undeveloped. Anal angle lost in

males and reduced in females.

Abdomen dark bronze-green, cylindrical, tergal overlap of segments

mat black; unmodified segments together nearly twice as long as

mesonotum. 1st-6th abdominal tergits and sternits well developed,

simple. Hypopygium pedicillate, epandrium attached to the tip of 7th

tergit; 7th segment slightly longer than epandrium. Appendices short,

strongly sclerotized. Surstylus bifurcated.

Diagnosis. Bickelia is similar to Sciapus Zeller (sensu Bickel,

1994) and Mascaromyia Bickel in thoracic chaetotaxy, and overall

habitus. It is clearly distinguished from other genera of Sciapodinae

by distinct anterior preapical seta on middle and hind femora, narrow

tomentous face and frons, presence of vertical setae in both sexes,

presence of 2 fine ventral propleural setae, branched vein M, modified

hypopygium. Bickelia should be included in the key to world genera of

Sciapodinae (Bickel, 1994) as follows:

1. FII and/or FIII with distinct anterior preapical setae ..........2

- Femora without strong anterior preapical setae ..................4

2. FIII only with anterior preapical setae; propleuron without strong

ventral seta ......................................... Sciapus Zeller

- Both FII and FIII with anterior preapical setae; propleuron with

more or less strong ventral seta ..................................2a

2a. Lateral scutellar setae hairlike; ac usually present, short and

numerous; propleuron with 2 fine black ventral setae; M bifurcated ..

................................................... Bickelia gen.nov.

- Lateral scutellar setae strong; ac present as 2-4 long pairs;

propleuron with strong ventral seta; M 2 usually absent (Negrobovia

Bickel & Amesorhaga Bickel).........................................3

Etymology. The genus is named in honour of the Australian dipterologist

Dr. Daniel J. Bickel.

Included species:

guerini Parent, 1935:86 (Sciopus); Bickel, 1994:101 (Mascaromyia);

Mauritius, n.comb.

Parent described damaged female with some male secondary sex

characters (setation of fore coxae and femora, wing

shape). Indication of strong femoral preapical bristles attributes the

species to Bickelia.

parallela Macquart, 1842:175 (Psilopus); Parent, 1935:88 (Sciopus);

Bickel, 1994:101 (Mascaromyia); Mauritius, n.comb.

Parent redescribed extremely damaged female type-specimen using

indistinct characters. Indication of strong femoral preapical

bristles attributes it also to Bickelia.

subparallela sp.n.

Holotype and paratypes of the new species are conserved in the

Natural History Museum (London).

Bickelia subparallela sp.n. (Fig. 1, 2, 3)

Holotype. Male, Chagos Archipelago: Diego Garcia, East Point,

7.V.1971 / A.M. Hutson, B.M. 1971-346. Paratypes. 7 males and 9

females with the same label as holotype but with catching dates 6 &

8.V.1971; 2 males and 1 female, Chagos Archipelago: Diego Garcia,

Eclipse Point, 26.III & 1.IV.1971 / A.M. Hutson, B.M. 1971-346; 2

females, Chagos Archipelago: Diego Garcia, Eclipse Point, 3 &

10.IV.1971 / A.M. Hutson, B.M. 1971-346 / At light; 2 males and 3

females, Chagos Archipelago: Diego Garcia, Trois Picquet, 4.IV.1971 /

A.M. Hutson, B.M. 1971-346 / coconut woodland; 2 males and 3 females,

Chagos Archipelago: Diego Garcia, Trois Picquet, 5.IV.1971 / A.M.

Hutson, B.M. 1971-346 / open coconut grove; 1 male, Chagos

Archipelago: Diego Garcia, Simpson's Point, 2.IV.1971 / A.M. Hutson,

B.M. 1971-346; 1 male, Chagos Archipelago: Diego Garcia, Simpson's

Point, 2.IV.1971 / A.M. Hutson, B.M. 1971-346 / freshwater pool; 1

male and 3 females, Chagos Archipelago: Diego Garcia, Simpson's Point,

20.IV.1971 / A.M. Hutson, B.M. 1971-346 / At light; 1 male, Chagos

Archipelago: Diego Garcia, Pointe Marianne, 13.IV.1971 / A.M. Hutson,

B.M. 1971-346 / lagoon coast; 1 female, Chagos Archipelago: Diego

Garcia, Pointe Marianne, 17.IV.1971 / A.M. Hutson, B.M. 1971-346 / At

light; 1 male, Seychelles Is., Cascade, 10.III.1965, Tams and Nye,

B.M. 1966-72.

Description. Frons mat bronze-green, grey pollinose. Strong

vertical bristle bends forward, smaller postvertical one presents

nearly at end of postocular row. Face silvery-white, pollinose,

narrow, 4 times as high as wide in the middle. Epistome twice as wide

as clypeus. Palpi and proboscis very short, brown, covered with small

hairs, palpi also with a small black bristle. Antennae black, scape

brown. First flagellomere as long as heigh at base, subtriangle, with

rounded apex, slightly pubescent. Arista dorsal, microscopically

haired. Length ratio of scape to pedicel to first flagelomere to

arista - 0.3:0.4:0.6:3.5.

Mesonotum metallic green, with two mat black postalary spots and

with brownish reflection between dorsocentral bristles, slightly grey

polinose; pleura bronze-olive-green, grey pollinose. Five dorsocentral

bristles with 3d bristle somewhat smaller, with a few hairs in front

of them; at least 10 pairs of short acrostichals, slightly increasing

backwards. Scutellum with two strong bristles and two hairs from the


Legs yellow, simple, middle and hind coxae and apical segments of

tarsi mostly brown. Fore coxae from the front with yellow hairs and

three black apical bristles. Middle coxae from the front with a few

dark hairs and with two or three fine black bristle, from the outside

bare. Hind coxae with one long black external bristle, with several

dark anteroventral hairs. Hind trochanter with a dark hair. Fore

femora usually with short fine basoventral and posterior preapical

hairs. Fore tibiae with one anterodorsal, two posterodorsal and one -

three apical bristles. Fifth tarsomere slightly flattened. Length

ratio of fore coxa to femora to tibia to tarsus (segments from first

to fifth) - 3.3 : 5.1 : 5.0 : 3.2 : 1.5 : 1.1 : 0.7 : 0.7. Middle and

hind femora with a few black ventral preapical hairs and one strong

anterior preapical bristle. Middle tibiae with three strong

anterodorsal, three posterodorsal, one or two ventral, four or five

apical bristles. Length ratio of middle coxa to femora to tibia to

tarsus (segments from first to fifth) - 2.2 : 5.2 : 6.4 : 3.8 : 1.9 :

1.0 : 0.9 : 0.7. Hind tibiae with three anterodorsal, three

posterodorsal, two short ventral bristles. Hind basitarsomere usually

with short basoventral bristle. Length ratio of hind coxa to femora to

tibia to tarsus (segments from first to fifth) - 1.7 : 6.5 : 7.9 : 2.7

: 1.5 : 1.2 : 1.1 : 0.8.

Wings slightly darkened, veins brown. Costa with short simple

setulae, posterior border with short hairs. Ratio of parts of costa

between R 2+3 and R 4+5 to those between R 4+5 and M 1 - 1.7 : 0.7. M 1

arises perpendicularly from M 2, with rounded right angle bend, then

straight; M 1 and M 2 slightly diverged; crossvein m-cu straight,

forming obtuse external angle with M 1+2. Ratio of crossvein m-cu to

apical part of M1+2 (fork-handle) to apical part of M 3+4 - 1.5 : 2.6

: 1.5. Anal vein and lobe reduced. Anal angle absent. Halteres yellow.

Squamae yellow, with brown edging and dark bristles.

Hypopygium black-brown, with short hairs, pedicillate, attached

to the tip of 7th sternit. Epandrial lobe short, with 3 setae.

Appendices short, brown, strongly sclerotized. Cercus broad, hooked,

with 4 long and some short external setae and with 3 long apicoventral

thorns. Surstylus with ventral arm slightly larger than dorsal arm;

ventral arm with a few short apical setulae; dorsal arm also with 2 or

3 long setae.

Female. Similar to male except lacking male secondary sexual

characters, otherwise as follows: face grey pollinose, wide, with

parallel edges, 2.5 times as high as wide. Legs usually dark-yellow,

sometimes partly brownish; fore coxae with additional 2-4 black

basoventral bristles; fore femora with 3-5 ventral spines of various

length in basal half. Oviscapt: ninth hemitergit with 1 acanthophorite

and 2 long setae; cercus short and broad, with 1 apical seta. Anal

lobe slightly developed; anal angle obtuse.

Length: body 2.4-3.1 mm; body with antennae 2.9-3.6 mm;

wing-length 2.1-2.7 mm; wing-width 0.7-0.8 mm.

Distribution: Chagos Archipelago, Seychelles.

Diagnosis. Males of Bickelia subparallela sp.n. appear closely

related to B. guerini, and females - to B. parallela. Most paratypes

of new species were collected from Chagos Archipelago, although a male

was found in Seychelles, while other species were described from

Mauritius. Keeping in mind poor differentiation between females of

related sciapodine genera, I can propose the next key to the species

of Bickelia:

1. Fore femora without strong bristles...............................2

- Fore femora with four strong black anteroventral bristles


2. Distinct acrostichal setae in two rows (male).......B. subparallela

- Acrostichals absent (female).............................B. guerini

3. Anal vein present, two scutellar bristles only.........B. parallela

- Anal vein reduced, two strong scutellars and two lateral hairs

from the outside....................................B. subparallela


I am sincerely grateful to Dr Brian Pitkin for his kindness in

giving me the opportunity to study the collection of the Natural

History Museum (London). I appreciate the help I have received from

Mrs Galina Grichanova in doing the illustrations.


Bickel D.J. 1994. The Australian Sciapodinae (Diptera: Dolichopodidae),

with a review of the Oriental and Australasian faunas, and a world

conspectus of the subfamily. - Rec. Austral. Mus., 1994, Suppl. 21: 1-394.

Parent O. 1935. Dipteres Dolichopodides nouveaux. - Encycl.

Entomol. (B) Diptera, 8: 59-96.

Remark under figures

Fig. 1. Bickelia subparallela sp.n., habitus.

Fig. 2. Bickelia subparallela sp.n., hypopygium.

Fig. 3. Bickelia subparallela sp.n., oviscapt (dry specimen).

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