AFROTROPICAL SPECIES OF THE SUBGENUS KALOCHETA BECKER (DIPTERA:

DOLICHOPODIDAE: CHRYSOSOMA GUERIN-MENEVILLE)

Igor Ya. GRICHANOV

Grichanov, I.Ya. Afrotropical species of the subgenus

Kalocheta Becker (Diptera: Dolichopodidae:

Chrysosoma Guerin-Meneville)

The first descriptions of the females of Chrysosoma

(Kalocheta) collarti and C. (K.) cucana

from Kenya and Uganda, catalogue and a key to Afrotropical

species of Kalocheta are given.

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

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

Key words: Diptera, Dolichopodidae, Chrysosoma (Kalocheta),

Africa, Kenya, Uganda.
 
 
 
 

The genus Kalocheta was established by Becker (1923) for two

females of Kalocheta passiva Becker from Camerun, and is closely

related to the genus Chrysosoma Guerin-Meneville, distinguishing only

by the widened lancet-shaped arista on the third antennal segment. As

in original description, the strap-like part of the arista is four

times as long as the hair-like portion. Later Curran (1925, 1927a,

1927b) and Parent (1929, 1933) found the species in Congo and Zaire

mentioning females and males but without concise descriptions.

A further four new species were described, mostly by males. Males

of Kalocheta liberia Curran (1929) have the hair-like part of arista

 s long as the strap-like portion. This proportion was not defined

exactly for females. Males of Kalocheta collarti Parent (1933) have

the hair-like part of arista as long as the strap-like part. Females

were unknown. Males of Kalocheta villiersi Vanschuytbroeck (1970) have

the hair-like part 1.5 times as long as the widened part, and females

have filiform arista. The last statement is need cofirmation because

widened arista are characteristic of the genus. At last males of

Kalocheta cucana Negrobov & Kulibali (1983) have the ratio of

strap-like to hair-like parts of arista - 2.5:4.5. Females were

unknown. Bickel (1994) synonymized Kalocheta with Chrysosoma. Here I

consider Kalocheta as subgenus of Chrysosoma Guerin-Meneville, stat.

nov.

Revising the collection of the Natural History Museum (London) I

found two series of males and females of C.(K.) collarti, and one

female that is most nearly related to male of C.(K.) cucana. It

appeared that females had the strap-like part of arista 4 or more

times as long as the hair-like part, and males had the same part twice

as short as the filiform portion. The series of C.(K.) collarti

specimens also showed the sex and/or individual variability of such

characters as colour of antennae, halters, coxae, femora and tibiae

(from yellow in females to brown in males), shape and color intensity

of brown spots on wings, number and strength of dorsocentral bristles

(partly reduced in males) and postvertical bristles (partly reduced

in females).

Below are the first descriptions of the females of C.(K.)

collarti and C.(K.) cucana.

Chrysosoma (Kalocheta) collarti Parent

Female. Corresponds to male described by Parent (1933) with the

exception of the following characters. Antennae yellowish-brown.

Proportion of length to height of first flagellomere - 1.1:0.7.

Proportion of length of lancet-shaped part to thread-like parts of

arista - 8.4:1.2. Strap-like part of arista approximately 12 times as

long as width of arista. One pair of strong postvertical bristles near

the upper edge of eyes. 3 pairs of strong acrosticals and 5 pairs of

strong dorsocentrals. Legs yellow; fore coxae in basal forth, middle

and hind coxae and trochanters, hind tibiae near apex, hind tarsus,

apical segments of fore and middle tarsi brown. Length ratio of fore

coxae, femora, tibiae to tarsi (segments from first to fifth) -

7.4:11.0:12.2:8.0:2.3:1.3:1.0:1.3. Middle tibiae with 3 dorsal, 3-4

anterior and 2-3 ventral bristles, without long bristles. Length ratio

of middle femora, tibiae to tarsi (segments from first to fifth) -

14.2:18.0:14.5:3.7:2.2:1.1:1.1. Length ratio of hind femora, tibiae

to tarsi (segments from first to fifth) -

18.0:23.0:9.2:4.1:2.5:1.4:1.4. Halters yellow.

Length: body - 5.9 - 7.7 mm (with antennae - 9.0 - 10.7 mm), wing

- 6.6 - 7.7 mm.

Material examined: 8 males, 15 females, Kenya: 18.XII.1970 (A.E.

Stubbs), B.M. 1972-211. Kakamega, Forest, 5200 feet; 1 male, Uganda

Prot., S. of L. George, 3200-3400 ft, 17-19 Oct. 1911 (S.A. Neave); 2

females, Uganda Prot., Tero Forest, S.E. Buddu, 3800 ft, 26-30 Sep.

1911 (S.A. Neave) [The last 2 females det. by C.E. Dyte, 1963 as K.

passiva Beck.].

Chrysosoma (Kalocheta) cucana Negrobov et Kulibali

Female. Corresponds to male described by Negrobov and Kulibali

(1983) with the exception of following characters. Antennae red-brown.

Proportion of length and height of first flagellomere - 1.1:0.7.

Proportion of length of lancet-shaped and thread-like parts of arista

- 8.5:1.4. Strap-like part of arista approximately 11 times as long as

width of arista. One pair of strong postvertical bristles near the

upper edge of eyes. 3 pairs of strong acrosticals and 5 pairs of

strong dorsocentrals. Legs light-yellow; fore coxae in basal forth,

middle and hind coxae and trochanters, apical segments of tarsi brown.

Femora without long hairs. Length ratio of fore coxae, femora, tibiae

and tarsi (segments from first to fifth) -

6.2:10.8:12.9:7.9:1.9:1.4:0.9:1.0. Middle tibiae with 3-4

postero-dorsal, 5 antero-dorsal, 2 antero-ventral and 2

postero-ventral bristles, without long hairs. Length ratio of middle

femora, tibiae and tarsi (segments from first to fifth) -

13.2:17.8:10.4:3.4:1.5:1.0:0.8. Length ratio of hind femora, tibiae

and tarsi (segments from first to fifth) -

15.0:21.3:8.3:2.4:3.3:1.2:1.3. Halters yellow.

Length: body - 5.5 mm (with antennae - 8.5 mm), wing - 6.4 mm.

Material examined: 1 female, Uganda, Kigezi dist. Kayonza,

2-4.XI.1964 (R.W. Crosskey).

Analysis of sex variability in species of the subgenus Kalocheta,

especially analysis of ratio of parts of arista, leads to supposition,

that references of C.(K.) passiva from Congo and Zaire should refer to

other Kalocheta species, and the female description of C.(K.)

villiersi has nothing to do with Kalocheta. A new key to the species

of Kalocheta is proposed below, with the exception of sex variable

characters.

List of known species of Kalocheta

Kalocheta Becker, 1923:41. Type-species: Kalocheta passiva

Becker, 1923, by monotypy.

collarti Parent, 1933:35. - Zaire, Tanzania, Kenya, Uganda.

cucana Negrobov et Kulibali, 1983:1121. - Zaire, Uganda.

liberia Curran, 1929:5. - Liberia.

passiva Becker, 1923:42. - Camerun, Congo(?), Zaire(?).

villiersi Vanschuytbroeck, 1970:267. - Congo.

Key to the species of Kalocheta

Males and females

1. Wings transparent, slightly darkened along veins ............

.............................. C.(K.) cucana Negrobov & Kulibali

- Wings with brown spots.......................................2

2. Squamae with white hairs..... C.(K.) villiersi Vanschuytbroeck

- Squamae with black hairs or bristles.........................3

3. Face thinly whitish pollinose, propleural hairs black, fore

coxae with white hairs and black bristles.. C.(K.) liberia Curran

- Only epistome greyish pollinose, clypeus metallic green......4

4. Fore coxae without hairs, only with black bristles; apical and

median brown spots have crosspiece along R 4+5 and M 1+2 wing

veins...................................... C.(K.) passiva Becker

- Fore coxae with white hairs and black bristles; apical and

median brown spots have crosspiece near junction of M 3+4 and

posterior transverse wing veins........... C.(K.) collarti Parent

Males

1. Strap-like part of arista as long as hair-like part of

arista .................................... C.(K.) liberia Curran

- Hair-like part of arista 1.5-2 times as long as strap-like

portion.........................................................2

2. Wings transparent, slightly darkened along veins ...........

............................... C.(K.) cucana Negrobov & Kulibali

- Wings with brown spots .....................................3

3. Hair-like part of arista 1.5 times longer than strap-like

part, squamae with white hairs ......K. villiersi Vanschuytbroeck

- Hair-like part of arista twice as long as strap-like part,

squamae with black hairs ......................K. collarti Parent

Acknowledgement

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).

References

Becker Th. 1923. Dipterologische Studien: Dolichopodidae. D.

Aethiopische Region. - Entomol. Mitteilungen, 12, 1: 1-50.

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.

Curran C.H. 1925. The Dolichopodidae of the South African Museum.

- Ann. S. Afr. Mus., 23, 1: 377-418.

Curran C.H. 1927a. Diptera of the American Museum Congo

Expedition. - Bull. Amer. Mus. Nat. Hist., 57, 2: 33-89.

Curran C.H. 1927b. Records and description of Ethiopian

Dolichopodidae. - Rev. Zool. Afr., 15, 2: 241-266.

Curran C.H. 1929. New Dolichopodidae from Liberia and the Belgian

Congo. - Amer. Mus. Novit., 391: 1-10.

Negrobov O.P. & Kulibali B. 1983. A new species of the genus

Kalochaeta (Diptera, Dolichopodidae) from Zaire. - Zool. Zhurn., 62,

7: 1120-1122 (in Russian).

Parent O. 1929. Les Dolichopodides de la Region Ethiopienne.

Etude Systematique. - Bull. Soc. Roy. Entomol. d'Egypte, 13, 4:

151-190.

Parent O. 1933. Etude sur les Dipteres Dolichopodides de Musee du

Congo (Tervueren). - Rev. Zool. Bot. Afric., 24, 1: 1-49.

Vanschuytbroeck P. 1970. Contribution a la faune du Congo

(Brazzaville). Mission A. Villiers et A. Descarpentries. XCVI.

Dipteres Dolichopodidae et Sphaeroceridae. - Bull. de l'I.F.A.N., 32,

A, 1: 262-268.