A brief review of the Afrotropical fauna of the subfamily

Hydrophorinae (Diptera: Dolichopodidae) with description of

Cemocarus stuckenbergi sp.n.

Igor Ya. GRICHANOV

Grichanov, I.Ya. A brief review of the Afrotropical fauna of the

subfamily Hydrophorinae (Diptera: Dolichopodidae) with description of

Cemocarus stuckenbergi sp.n.

Cemocarus stuckenbergi sp.n. from South Africa is described. New

records, keys to the African hydrophorine genera and to recognizable

Afrotropical species of Hydrophorus are given.

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

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

Key words: Diptera, Dolichopodidae, Hydrophorinae, Cemocarus,

Hydrophorus, Orthoceratium, Tropical and South Africa.

Introduction

The world fauna of the subfamily Hydrophorinae numbers more than

30 genera, of which 6 genera occur in the Afrotropical Region. The

Palearctic fauna of the subfamily was recently revised by Negrobov

(1977-1979), Nearctic fauna by Hurley (1985), and Oriental fauna

(partly) by Meuffels & Grootaert (1984) and Grootaert & Meuffels

(1988, 1993). The last authors described Cemocarus, a new monotypic

genus of Hydrophorinae from South Africa. Rampini & Munari (1986) gave

a key to known Afrotropical species of the genus Aphrosylus Haliday.

Dyte (1967) and Negrobov e.a. (1987) reviewed known Afrotropical

species of the genus Liancalus Loew. Grichanov (in litt.) gave a list

and a key to known Afrotropical and Palearctic species of the genus

Thinophilus Wahlberg. The first record of the genus Orthoceratium from

Afrotropics is given in this paper. Several other North African genera

can be found in Africa south of Sahara. Catalogue of the Afrotropical

genera and key to all African genera are represented below.

Treating unidentified material from the collections of the Natural

History Museum, London (NHML), the Hungarian Natural History Museum

(HNHM), and Lund University (Lund), I found many interest hydrophorine

species. In this paper descriptions of Cemocarus stuckenbergi sp.n.

from South Africa and new records for known African species are given.

Catalogue and key to species of Hydrophorus Fallen are also

represented.

The most interest distribution of species are as follows:

Hydrophorus praecox Lehmann - all zoogeographical regions;

Orthoceratium lacustre (Scopoli) - Europe (except North), Algeria,

Tunisia, Madeira, Tanzania (!); Thinophilus indigenus Becker - Cape

Verde Is., Ethiopia, South Yemen, Nigeria, Benin, Ghana, Zaire,

Tanzania, Madagascar, Angola, Namibia, South Africa, Swaziland;

Palearctic and Oriental Regions; Thinophilus mirandus Becker -

Algeria, Morocco, Tanzania.

Holotype and paratypes of the new species are conserved in the

Natural History Museum (London).

List of Afrotropical genera of Hydrophorinae

Aphrosylini

Aphrosylus Haliday in Walker, 1851:220

Thinophilini

Thinophilus Wahlberg, 1844:37

Hydrophorini

Hydrophorus Fallen, 1823:2

Liancalus Loew, 1857:22

Orthoceratium Schrank, 1803:55

Cymatopini, new tribe

Cemocarus Meuffels & Grootaert, 1984:152

Key to African genera of Hydrophorinae

1. Labellae hook-shaped in lateral view, with long recurved, generally

protruding hypopharynx............................................2

- Labellae normal in lateral view, without long protruding

hypopharynx.......................................................3

2. Arista apical; fore tibia at apex with distinct erect spinose seta;

male hind basitarsomere simple, without strong seta................

.................................................Aphrosylus Haliday

- Arista dorsal; fore tibia without spinose seta at apex; male

hind basitarsomere curved, with strong seta........Teneriffa Becker

3. Acrostichals absent; scutellum with 2 or 4 strong setae...........4

- Acrostichals present, or if absent, then scutellum with 6 setae...6

4. Arista apical (males) or subapical (females); 4 dorsocentrals; wing

somewhat darkened.................................Schoenophilus Mik

- Arista dorsal, other features various.............................5

5. Tibiae usually with strong setae; M1+2 usually curved; at least 5

dorsocentrals, or if 4 dc, then male cercus long, at least half as

long as abdomen................................Thinophilus Wahlberg

- All tibiae without apical setae; R2+3, R4+5, and M1+2 straight and

parallel; 4 dorsocentrals; wing hyaline; male cercus short.........

.............................................Paralleloneurum Becker

6. First flagellomere trapezoidal, with subapical arista located in

dorso-apical excavation; 6th and 7th male terga well developed.....

.....................................Cemocarus Meuffels & Grootaert

- First flagellomere rounded, oval or subtriangular, without

dorso-apical excavation; at least 7th male tergum greatly reduced..7

7. Mesonotum with small setae; no more than one pair of dorsocentrals;

acrostichals in two rows; arista subapical....Anahydrophorus Becker

- Mesonotum with several strong dorsocentrals; acrostichals in one

row, rarely absent; arista usually dorsal.........................8

8. Fore femora thickened, ventrally with strong bristles and spines;

first flagellomere with apico-ventral incision...Hydrophorus Fallen

- Fore femora not thickened, without strong ventral bristles or

spines; first flagellomere without incision.......................9

9. Scutellum with 4 setae; hind femora flat; wing veins unmodified

except M1+2 with two right angle bends in males and fair sinuation

in females....................................Orthoceratium Schrank

- Scutellum usually with 6 setae; hind femora cylindric; males

and often females with wing veins variously modified, but M1+2

without double right angle bend......................Liancalus Loew

Hydrophorus Fallen

The genus occurs widely across the whole world including

high-latitude islands and mountains with species confined mostly to

the water surface of various reservoirs. The Afrotropical species of

Hydrophorus are worst described and need redescription of type

material. Based on variable characters, original descriptions do not

comprise detailed drawings of hypopygium. Some species known only from

females should be probably synonymized with other species described by

males, and vice versa. For example, male H. incisicornis is possible

synonym of female H. spinicornis. Most part of known species can not

be reliably identified without studying male hypopygium structures,

especially surstylus. Records of the Palearctic species such as H.

balticus from South Africa should be probably belonged to H.

vaalensis. Several other species are awaiting to be synonymized or

declared Nominae Dubiae in future revisions of type material. The last

key to the African species of the genus (Vanschuytbroeck, 1952) was

based on individually and sexually variable characters. I suspect that

only four following species are really known from the Afrotropical

Region.

List of Continental Afrotropical species of Hydrophorus

(for references see Dyte & Smith, 1980)

aureifacies Becker, 1914:124 (male) - Kenya, [?Uganda, ?Tanzania,

?Zaire], ?South Africa

praecox Lehmann, 1822:42 - South Africa, Namibia, Angola, Botswana,

South Arabia, Ethiopia, Mauritania, Gambia, Nigeria, Kenya,

Tanzania, Mauritius, Rodriguez, Aldabra, St. Helena, Cape Verde

Islands, Canary Islands; Palearctic, Nearctic, Neotropical,

Oriental Regions, Australia, New Zealand

= inaequalipes Macquart, 1834:453 (Medeterus)

= schonherri Zetterstedt, 1843:444

= cinerea Perris, 1847:492 (Aphrozeta)

= aestum Loew, 1869:36

= vagus Hutton, 1901:34 (Liancalus)

= breviventris, Becker, 1903:60

= monodi Couturier, 1985:13, n. syn.

spinicornis Loew, 1858:373 (female) - South Africa, Zaire, [?Tanzania]

vaalensis Parent, 1954:226 (female) - South Africa, [?Namibia,

?Zimbabwe]

Doubtful species and records

arambourgi Parent, 1938:410 (female) - Kenya

balticus Meigen, 1824:66 (Medeterus) - Palearctic Region, St. Helena,

North and ?South Africa

= chloropus von Roser, 1840:56

chappuisi Parent, 1938:411 - Kenya

congoensis Vanschuytbroeck, 1951:74 - Zaire, Tanzania

hydrophylax Parent, 1939:275 - Uganda, ?Namibia

incisicornis Speiser, 1910:111 (male) - Tanzania

jeanneli Parent, 1938:411 - Kenya, Zaire, Tanzania, ?Namibia

ochraceus Becker, 1914:124 (female) - Kenya, Uganda

variinasutus Vanschuytbroeck, 1951:76 - Zaire

Key to recognizable species of Hydrophorus from Continental Afrotropics

1. Apex of first flagellomere reddish or yellow; wing distinctly

maculated....................spinicornis Loew; incisicornis Speiser

- First flagellomere entirely black; wing monochrome, hyaline or

infumated along veins.............................................2

2. Face entirely greyish-white, without metalic reflection; anterior

tibia apically with sharp dens; wing with yellow veins at

base; dorsal lobe of surstylus with long ventral process...........

....................................................praecox Lehmann

- Epistome at least partly shining metallic; clypeus white in males

and yellowish in females; anterior tibia apically without dens;

wing with brown veins; dorsal lobe of surstylus without long

ventral process...................................................3

3. Hypandrium as long as surstylus, with rounded apex; epandrium with

narrow setiferous process at base of surstylus; female clypeus

rusty-yellow....................................?aureifacies Becker

- Hypandrium half as long as surstylus, with conoid apex; epandrium

without such process, with short dens at base of surstylus; female

clypeus yellowish-grey............................?vaalensis Parent
 
 

Hydrophorus praecox Lehmann

(Figs. 1-5)

Material examined. Male and female, Saudi Arabien, W. Buttiker /

Araida, 20.10.75, Selouly's Farm [NHML]; female, Nigeria: Samaru,

15-22.VI.1970, P.H. Ward, B.M. 1970-604 / Mercury vapour light trap;

female, Tanzania: Matombo, Morogoro reg. / 11.IX.1977, leg. Mahunka

[HNHM]; male & female, Gambia: 3 km NW Central Banjul garden at Wadner

Beach Hotel, 21.II.1977, Loc. No. 1A, At light 19.00 - 21.00, UTM

28PCK257891 / Lund Univ., Syst. Dept., Sweden Gambia/Senegal.

Febr.-March 1977, Cederholm - Danielsson - Larsson - Mirestrom -

Norling - Samuelsson; male, Gambia: oil palm and mangrove vegetation

close to the beach, about 5 km SSW Gunjur. At light 19.00 - 22.00,

22.II.1977, Loc. No. 8, UTM 28PCK05-54 / Lund Univ., Syst. Dept.,

Sweden Gambia/Senegal. Febr.-March 1977, Cederholm - Danielsson -

Larsson - Mirestrom - Norling - Samuelsson; 2 males & 1 female, South

West Africa (W22), Kuiseb river canyon, 22-23.I.1972, Riverside

vegatation / Southern African Exp. B.M. 1972-1; 2 males & 1 female,

South West Africa (W32), Windhoek, Race-Course, 5.II.1972, Low

vegatation / At light / Southern African Exp. B.M. 1972-1; 1 male,

South West Africa (W24), Walvis bay, 25-26.I.1972, Pool edge in dunes

/ Southern African Exp. B.M. 1972-1; 1 male, South West Africa (W32),

Windhoek, environs, 6.II.1972, At light / Southern African Exp. B.M.

1972-1; 7 males & 1 female, S.W. Africa (18), Sossusvlei, Diamond Area

No.2, 20-21.I.1972 / Southern African Exp. B.M. 1972-1; 7 males & 1

female, S.W. Africa (W43), Onguma Fm., 55 mls NW Tsumeb, 17-19.II.1972

/ Southern African Exp. B.M. 1972-1; 20 males & 21 females, S.W.

Africa (25), Swakopmund, 26-30.I.1972 / general sweeping / swept

vegetation around sewage farm settling tanks / Southern African Exp.

B.M. 1972-1; 1 male & 1 female, S.W. Africa (11), Aar Farm, 25 mls ESE

Aus, 15-17.I.1972 / Southern African Exp. B.M. 1972-1; 1 male, S.W.

Africa (W36), Otjikoko Sud Fm., 33 mls ENE Omaruru, 10-13.II.1972 /

Southern African Exp. B.M. 1972-1; 1 male, S.W. Africa (19), Sesriem

Canyon, 3 mls W Sesriem, 21-22.I.1972 / Southern African Exp. B.M.

1972-1; 1 male, S.W. Africa (W37), Otjitambi Fm., 27 mls ESE Kamanjab,

13-15.II.1972 / Southern African Exp. B.M. 1972-1; 1 male, S.W. Africa

(17), Sesriem Sud Fm., Maltanhoe distr., 19-20.I.1972 / general

sweeping / Southern African Exp. B.M. 1972-1; 2 females, S.W. Africa

(23), Homeb, 10 mls ESE Gobabeb, 23-25.I.1972 / Southern African Exp.

B.M. 1972-1; 1 female, S.W. Africa (32), Windhoek, 4-10.II.1972 /

Southern African Exp. B.M. 1972-1; 1 male & 12 females, Angola (A34),

Lobito, 19-20.III.1972 / Southern African Exp. B.M. 1972-1; 4 females,

Botswana (B7), Kuke Pan, 20o59'S, 22o25'E, 14-15.IV.1972 / Southern

African Exp. B.M. 1972-1; 2 females, S. Afr. Transvaal, Zontpan N om

Pretoria, 19.6.1955, G. Rudebeck [Lund]; male, [Russian Far East:]

Yevreiskaya AO, vil. Amurzet, 18.08.1991, Grichanov [Author's Coll.];

female, [Kazakhstan:] Tselinograd Region, Novoishimka, 13.08.1989,

Grichanov [Author's Coll.]; 6 males and 1 female, [South Russia:]

Rostov Region, Azov distr., Port-Katon, 17.05.1994, 25.04.1995,

6.06.1996, Grichanov [Author's Coll.].

Diagnosis and variability. H. praecox is well distinguished by

black antenna, entirely greyish-white face, yellow veins at base of

wing, and sharp dens at apex of anterior tibia (see descriptions of H.

praecox by Takagi, 1967, and Negrobov, 1977). Males have dorsal lobe

of surstylus with long ventral process. Many morphological characters

of this species are widely variable. Dorsocentral setae on mesonotum

can be somewhat weaker or stronger, the face narrower or wider, gena

lower or higher, antenna and arista longer or shorter with various

ratio of articles in individuals. The number and strength of ventral

spines on anterior femora are also variable to some extent. Moreover,

hypopygium structures can vary in some specimens (Figs. 1-5). Examined

males from Gambia, South Arabia, and Rostov Region (Russia) have

ventral lobe of surstylus distinctly shorter than dorsal lobe (see

also figures in Takagi, 1967, and Negrobov, 1977), whereas males from

the Russian Far East, Namibia and Angola have ventral lobe reaching

apex of dorsal lobe. The length of ventral process of dorsal lobe, the

number and length of apical and subapical setae on the process and

lobes of surstylus also vary, especially in individuals of South

African population. Most part of 9 examined males (including 3

specimens from Namibia) have hypandrium with conoid apex (as figured

by Negrobov, 1977), whereas males from Gambia and Angola, and a male

from Swakopmund (Namibia) have hypandrium with rounded apex. Couturier

(1985) described H. monodi from Mauritania having no significant

differences in external morphology from H. praecox except wide

membranous area ("sicatrix") on 5th tergum laterally. Examined males

from Gambia have this sicatrix embracing approximately 1/2 to 2/3

lateral surface of 5th tergum and looking like an excavation in dried

specimens. Despite the remark of Couturier, examined males of H.

praecox from Palearctic and Afrotropical Regions also have the

membranous area on both sides of this tergum, although the size of

sicatrix is greatly variable and usually much smaller (from 1/10 to

1/2 lateral surface). The structure of surstylus in Gambian males is

closest to this in European males. This and all other variable

characters do not correlate with each other. So, I regard H. monodi as

synonym of H. praecox.

Distribution: South Africa, Namibia, Angola, Botswana, South

Arabia, Ethiopia, Mauritania, Gambia, Nigeria, Kenya, Tanzania,

Mauritius, Rodriguez, Aldabra, St. Helena, Cape Verde Islands, Canary

Islands; Palearctic, Nearctic, Neotropical, Oriental Regions,

Australia, New Zealand

Hydrophorus ?aureifacies Becker

(Fig. 6)

Material examined. Male, Kenya: Aberdare Range, 26.X.1934,

B.M.E.Afr.Exp. B.M.1935-203 / Mt. Kinangop, 10000 ft, F.W. Edwards; 3

females, Kenya: Mt. Elgon, II.1935, B.M.E.Afr.Exp. B.M.1935- 203 /

Heath Zone, 10500-11500 ft., F.W. Edwards / Alpine Zone, 12000-13000

ft., F.W. Edwards; 4 males & 9 females, Kenya: Mt. Kenya, N.side,

11000-13500 ft / Heather, stream / swept, 20-22.XII.1980, P.S.

Cranston, B.M. 1981-79.

Diagnosis. Examined specimens reveal nearly the same extent of

variation as this in H. praecox. Characters used in original

descriptions and keys to African species (thickness and colour of head

and body pollination, wing infumation, colour of halter and postocular

cilia, length and strength of spines on anterior legs etc.) are

greatly variable and insufficient for reliable identification of

species. It is quite possible, that the following species described

from Equatorial Africa should be synonymized with H. aureifacies (see

also description of this species in Becker, 1923): H. arambourgi

Parent, H. chappuisi Parent, H. congoensis Vanschuytbroeck, H.

hydrophylax Parent, jeanneli Parent, ochraceus Becker, and

variinasutus Vanschuytbroeck. First flagellomere entirely black;

epistome at least partly shining metallic; clypeus white in males and

rusty-yellow in females; anterior tibia apically without dens; wing

with brown veins, usually infumated; colour of halter varies from

dirty-yellow to mostly blackish; hypandrium as long as surstylus, with

rounded apex; epandrium with narrow setiferous process at base of

surstylus; dorsal lobe of surstylus without long ventral process,

slightly sinuate, with strong dorsal seta at base and short ventral

preapical seta; ventral lobe longer than dorsal one, strongly curved

at apex.

Distribution. Kenya, [?Uganda, ?Tanzania, ?Zaire], ?South Africa.

Hydrophorus ?vaalensis Parent

(Fig. 7)

Material examined. Male & female, RSA: Cape Prov. 15 km E.

Darling, 150 m, 33o26'S, 18o32'E, 04.X.1994, Loc. 3, leg. R.

Danielsson [Lund]; 2 males & 7 females, S. Africa (S6), C.P.

Silvermine, N.R. Cape penin, 2-3.I.1972. / Southern African Exp. B.M.

1972-1; male & female, S. Rhodesia, Luyanga, 16.XI.1948, J.

Omer-Cooper [NHML].

Diagnosis. Parent (1954) described H. vaalensis by a female from

South Africa, using variable or insignificant characters (see

diagnosis of H. ?aureifacies in this paper). It is impossible to

distinguish this species from other Afrotropical species except H.

spinicornis, H. incisicornis, and H. praecox by published

descriptions. I belong examined material to H. vaalensis, because this

is the only doubtful species, that was described from South Africa.

Records of H. aureifacies, H. balticus, H. jeanneli, and H.

hydrophylax from South Africa and Namibia should be probably refered

to H. vaalensis. The two recognizable species, H. ?aureifacies and H.

?vaalensis, have no significant differences in external morphology

except structures of hypopygium. Wing of the last species is somewhat

paler; halter usually yellow or brownish; hypandrium half as long as

surstylus, with conoid apex; epandrium without process, with short

dens at base of surstylus; dorsal lobe of surstylus without long

ventral process, slightly sinuate, with strong dorsal seta at base and

short ventral preapical seta; ventral lobe longer than dorsal one,

slightly curved at apex; female face yellowish-grey.

Distribution. South Africa, [?Namibia, ?Zimbabwe].

Liancalus Loew

See Dyte, 1967, Negrobov, 1978, 1979b, and Negrobov e.a., 1987

for generic diagnosis, key and descriptions of known species. Six

species are found in Africa from South to Sub-Saharan Region.

Liancalus adenensis Dyte, 1967

Material examined. Female, Ethiopia: Simien, W. of Derasghie, over

9000 ft., 23.XII.1952 / From chapel in cave in basaltic cliff [printed

label] / from damp rock in hoof of chapel (in basaltic rock)

[hand-written label] / N. Ethiopia: 1952-1953, Hugh Scott, B.M.

1953-335.

Diagnosis. L. adenensis differs from other species by 3 pairs of

scutellar setae, short claws on legs (half as long as apical tarsal

segment), uniseriate acrostichals, strongly curved vein M just before

apex. Examined female differs from this described in Dyte (1967) by

smoky spot above M1+2 before its crossing with m-cu.

Distribution: Yemen, Ethiopia (!)

Orthoceratium Schrank

See Negrobov (1978, 1979) for generic diagnosis and descriptions of

two known species. Here is the first record of the genus from the

Afrotropical Region.

Orthoceratium lacustre (Scopoli)

Musca lacustris Scopoli, 1763:343

Musca formosus Haliday, 1832:356

Medeterus viridipes Macquart, 1834:452

Orthoceratium lacustre (Scopoli); Negrobov, 1979:419

Material examined. 2 males & 1 female, Tanzania: Kimboza, Forest

Reserve / 11.IX.1977, leg. Mahunka [HNHM];

Diagnosis. O. lacustre differs from the second known species, O.

sabulosum (Becker), by smaller size, wider face, hyaline wing, and

presence of ventral process on 4th and 5th abdominal segments.

Hypopygium structures are identical to these figured by Negrobov

(1979).

Distribution: Europe (except North), Algeria, Tunisia, Madeira,

Tanzania (!).

Cemocarus Meuffels & Grootaert

See Meuffels & Grootaert (1984) for generic diagnosis and

redescription of type species. The genus has no analogies in

Afrotropical Hydrophorinae. It is related to widely distributed

tropical genus Cymatopus Kertesz, 1901, and Oriental genus

Thinolestris Grootert & Meuffels, 1988. Only two species are known at

present.

Cemocarus griseatus (Curran)

Aphrosylus griseatus Curran, 1926:403;

Cymatopus capensis Parent, 1939:256;

Cemocarus griseatus (Curran) Meuffels & Grootaert, 1984:153.

Material examined. 6 males & 5 females. S.W. Africa (25),

Swakopmund, 26-30.I.1972 / general sweeping / Southern African Exp.

B.M. 1972-1; female, Van Staadens, Pass. E. Cape Prov., S. Africa,

Stuckenberg, V. 1959 [NHML].

Distribution: South Africa, Namibia (!).

Cemocarus stuckenbergi sp.n.

(Fig. 8)

Holotype, male, Van Staadens, Pass. E. Cape Prov., S. Africa /

Coll. B. & P. Stuckenberg, V. 1959 [NHML].

Paratypes, male & female, the same labels.

Description. Frons, face, occiput, palpus, and proboscis with

bronze-black ground color, grey pollinose. A row of strong black

postocular setae, one pair of strong occipital, vertical, and

postvertical setae present. Ocellar tubercle with one pair of strong

setae and several pairs of short hairs. Ventral postcranium with

sparse black irregular cilia supplementing postocular row. Eyes

haired, emarginated near base of antennae. Face wide, the narrowest

near suture. Ratio of height of epistome to its minimal width to

height of clypeus to its maximal width to height of palpus, 20 : 16 :

19 : 26 : 25. Antenna black, scape vase-like, pedicel with short

setae, first flagellomere as long as heigh, trapezoid, with

dorso-apical excavation bearing short arista, with short hairs. Arista

bisegmented, thick and haired at base, otherwise fine and bare. Length

ratio of scape to pedicel to first flagellomere to arista, 12 : 5 : 15

: 32. Palpus and proboscis with short black hairs.

Thorax bronze-black. Six strong dorsocentral bristles, the last

one is the longest; microscopic acrostichals in one irregular row

extending to the 4th dorsocentral seta. Prothorax with several black

cilia. Scutellum with 2 pairs of strong black setae.

Legs mostly black, without strong setae or long hairs,

trochanters and apices of femora light brown, tarsi dark-brown. Fore

and middle coxae with black hairs anteriorly, hind coxa with one fine

external seta. Fore femora and tibia with a row of short black erect

ventral setulae. Fore tibia with short apico-ventral scale. Fifth

tarsomere of all tarsi enlarged and flattened. Length ratio of fore

coxa to femora to tibia to tarsus (segments from first to fifth), 30 :

54 : 42 : 20 : 8 : 6 : 5 : 7. Same ratio for middle leg, 23 : 56 : 57

: 32 : 11 : 6 : 5 : 8. Same ratio for hind leg, 20 : 72 : 69 : 19 : 19

: 9 : 7 : 9.

Wings darkened, veins brown. Ratio of R1 to wing length, 13 : 29.

Ratio of part of costa between R2+3 and R4+5 to this between R4+5 and

M1, 24 : 24. R4+5 and M1+2 straight, parallel in apical part. Ratio of

cross-vein m-cu to apical part of CuA1, 29 : 16. Lower calipter small,

yellow, with dark cilia. Halters yellow, greatly reduced.

Abdomen bronze-green with short black setae; six full terga

developed; 6th tergum nearly as long as 5th one; 7th tergum symmetric,

nearly 2/3 as long as 6th one; 8th segment approximately half as large

as epandrium. Hypopygium black, grey pollinose. Cercus brown,

gradually narrowed apicad, with short hairs along entire length,

reaching the end of surstylus. Surstylus brown, narrow, with rounded

apex, with several scattered short ventral hairs. Hypandrium narrow,

thick at base.

Female. Similar to male except lacking male secondary sexual

characters; fore femora and tibia without erect setulae.

Length: male body without antennae 4.3 mm, wing-length 4.3 mm,

wing-width 1.4 mm; female body 4.8 mm, wing-length 5.0 mm, wing-width

1.6 mm.

Distribution: South Africa.

Etymology. The species is named in honour of the South African

dipterologist Dr. B.R. Stuckenberg.

Diagnosis. The new species can be separated from C. griseatus

using the following key:

1. Acrostichals biseriate; m-cu approximately as long as apical part

of CuA1; size about 3 mm......................C. griseatus Curran

- Acrostichals uniseriate; m-cu nearly twice as long as apical part

of CuA1; larger species, 4.3 - 4.8 mm.......C. stuckenbergi sp.n.
 
 

Acknowledgements

I am sincerely grateful to Dr. Brian Pitkin, Dr. Laslo Papp, and

Dr. Roy Danielsson for their kindness in furnishing an opportunity to

study the collections of the Natural History Museum (London), the

Hungarian Natural History Museum (Budapest), and Lund University.
 
 

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

Couturier, G. 1985. Hydrophorus monodi, espece nouvelle de

diptere Dolichopodidae de Mauritanie. Revue Fr. Entomol. (N.S.), 7(1):

13-14.

Dyte, C.E. 1967. The genus Liancalus Loew (Diptera:

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Remark under figures

Figs. 1-5. Variation of hypopygium structures in Hydrophorus

praecox Lehmann. 1-2, hypandrium, lateral view; 3-5, dorsal lobe of

surstylus, ventro-lateral view.

Figs. 6-7. Apex of hypopygium, lateral view. 6, Hydrophorus

?aureifacies Becker; 7, Hydrophorus ?vaalensis Parent.

Fig. 8. Cemocarus stuckenbergi sp.n., hypopygium, lateral view.