A revision of Afrotropical Chyromyidae (excluding Gymnochiromyia Hendel) (Diptera: Schizophora), with the recognition of two subfamilies and the description of new genera
Author
Ebejer, Martin J.
text
African Invertebrates
2009
2009-12-31
50
2
321
321
http://www.bioone.org/doi/abs/10.5733/afin.050.0208
journal article
10.5733/afin.050.0208
2305-2562
7910603
Aphaniosoma atriceps
sp. n.
Fig. 36
Etymology: From Latin
ater
(dark) and
caput
(head), and refers to the distinctive (but not unique) dark brown antenna which gives the head a dark appearance.
Diagnosis: Yellow
fr
and contrasting dark brown antennal segment 3, very narrow gena, dark grey scutum and
scut
which has setae shorter than its length, tarsomere 5 of all legs brown, abdominal
tg
brown with narrow, pale yellow hind margins. Male postabdomen with no distinguishing external features, but internally with large dark
psg
and with pregenital
st
having ventrally projecting lobes near apex.
Description:
Male
.
Head
: Yellow,
ocp
dark grey to black,
oc
triangle black,
fr
narrow and converging anteriorly so that at level of antennae it is about 0.75 as wide as at level of anterior
oc
, face small, depressed and with distinct, narrow but low facial carina, eye narrow, oval, lying oblique, gena yellow, narrow, at middle about 0.3 height of eye and having numerous fine pale yellow setulae, 3 short setae at vibrissal corner, mouthparts yellow except for two small brown spots deep to proboscis an anterior margin of roof of buccal cavity, 8 setulae on
fr
with no longer setulae in front of
oc
triangle, 6 short
orb
, especially anterior 4, becoming progressively shorter from back to front, 1
vti
and 1
vte
,
pvt
distinct and convergent, ocellars long, divergent, antennal segment 3 dark brown contrasting with yellow segments 1 and 2, arista dark brown to base.
Thorax
: Scutum and
scut
uniformly dark grey,
mtn
entirely dark grey,
pprn
and
ntpl
yellow, pleura mostly dark grey, but for narrow yellow margins to sutures. Chaetotaxy: 1
pprn
, 1
posthu
, 1
ihu
, 2
ntpl
, 0+4
ia
, 1+5
acrs
, 3+5
dc
only the posterior one well-developed,
prpl
short, 1
pa
, 2 pairs of marginal
scut
, shorter than usual compared to congeners such that subapical setae, usually the longest, are here shorter than length of
scut
, 1 katepisternal and several setulae on anterior part of sclerite, 1 anepisternal, all setae pale, with shorter ones and setulae inconspicuous.
Fig.36.
Aphaniosoma atriceps
sp. n.
: (a) ơ hypopygium, lateral, scale bar = 0.15 mm; (b–d) ^postabdomen: (b) posterior, (c) lateral, (d) spermathecae, scale bar = 0.1 mm.
Wing: Hyaline and uniformly microtrichose, veins brown, distance between R
2+3
to R
4+5
on costal margin about 0.6 that between R
4+5
and M
1+2
, distance between crossveins about 1.7× length of posterior crossvein and length of apical section of Cu about 2.5× length of posterior crossvein. Haltere dusky yellow.
Legs: Yellow and fine yellow setulose, tarsomere 5 of all legs brown.
Abdomen
: Brown with narrow, pale yellow hind margins to all
tg
, especially on sides and on apical segments.
Postabdomen: Yellow with no distinctive external features.
Female
.
As male, but several specimens have diffusely infuscated femora dorsally over middle third. Postabdomen:
tg
7 complete and broader laterally;
cerc
and
hypr
more sclerotized than usual among congeners;
st
8 with small sclerites apically and just proximal to these, two small membraneous structures with single microtrichium in centre of each;
s
with short section of duct sclerotized.
Length
: ơ body 1.0 mm, wing
0.9 mm
; ^body
1.2 mm
, wing
1.1 mm
.
Holotype
: ơ
NAMIBIA
:
Khorixas District
,
Huab R.
at
Krone
, 721,
20°37'09"S
:
13°54'31"E
, sweeping grasses and sedges,
23–26.x.1998
,
A.H. Kirk-Spriggs
(
NMNW
).
Paratypes
: 2ơ 3^same data as holotype (
NMNW
);
2^Walvis Bay
, alt.
5 m
,
22°60'S
:
14°28'E
,
6.ix.2003
,
A. Freidberg
(
TAUI
)
.