A review of Afrotropical Sisyrnodytes Loew, 1856 (Diptera: Asilidae: Stenopogoninae)
Author
Londt, Jason G. H.
text
African Invertebrates
2009
2009-06-30
50
1
137
137
http://www.bioone.org/doi/abs/10.5733/afin.050.0106
journal article
10.5733/afin.050.0106
2305-2562
7910383
Sisyrnodytes dasykylon
sp. n.
Figs 19, 20
,
43
Etymology: From Greek
dasys
(thick with hair, shaggy) and
kylon
(parts below eyes). Refers to the well-developed mystax that is supplemented by long frontal setae.
Redescription:
Male
(based on
holotype
in excellent condition).
Head
: Dark red-brown to black, with mainly white setose except for a few pale yellowish postocular setae. Antennae: Dark brown except for yellowish tip of style. Scape and pedicel white setose. Major ventral setae of pedicel project beyond level achieved by postpedicel. Basal element of style short (shorter than broad). Eye to face width ratio 1.8:1. Mystax longish, white. Frons and vertex white setose. Laterally situated frontal setae extending below antennal sockets, mingling with mystax. Occipital setae white. Some postoculars yellowish. Palps and proboscis white setose.
Thorax
: Dark red-brown to black. Pronotum white and pale yellowish setose. Mesonotum extensively setose except for narrow paramedial strips and large sutural and postsutural areas. Lateral macrosetae white (
npl
) and yellowish (
spal
&
pal
), other setae white anteriorly, pale yellowish posteriorly. Scutellum apruinose with poorly defined transverse groove (has somewhat crinkled appearance); disc asetose, 20 pale yellowish apical setae (in single row). Pleural setae mostly white except for some yellowish setae dorsally on anepisternum and on katepimeron. Katatergals white, long, shafts more or less smooth. Legs: Dark red-brown, mainly white and pale yellow setose, but some black setae at apex of tibiae and ventrally on tarsi. Claws longish, dark red-brown; empodia moderately long, yellowish; pulvilli minute to absent. Wings 3.7×
1.5 mm
, C white setose basally, membrane transparent. Haltere with orange-brown knob, dark brown stalk.
Abdomen
: Dark red-brown to black, white setose. Tergal setae mostly long, reclinate laterally, short, rather transparent medially (giving the impression of asetose areas medially).
Genitalia: Not dissected, but visible structures appear to conform to dissected and illustrated topotypic
ơ
paratype
(
Figs 19, 20
). Epandrium moderately developed and simple in structure, proctiger not extending greatly beyond it. External lobe of gonocoxite in lateral view broadly rounded proximally, fairly acutely pointed distally. Internal lobe fairly robust. Gonostylus somewhat shorter than internal lobe of gonocoxite and simple in structure. Hypandrium flattish, sub-triangular in ventral view, with long gradually tapering medial lobe extending well beyond external lobe of gonocoxite. Aedeagus fairly slender with fairly blunt tip.
Female
: Similar to male but have more yellowish setae which may even be described as orange in colour and in a few instances these outnumber white setae.A few specimens may even have some orange abdominal setae.
Variation: Wing length
ơ
2.9–4.7 mm
,
^3.2
–5.4 mm
.
Holotype
:
ơ
SOUTH AFRICA
:
Northern Cape
: ‘
S Africa
:
Cape
#33 /
23km
SE of Middelpos
/
32°01'S
:
20°25'E
1200m
/
Date
:
28.xi.1990
/
Whittington
&
Londt
/
Banks of Visrivier’
(
NMSA
).
Paratypes
:
SOUTH AFRICA
:
Northern Cape
: 5
ơ 5^same
data as holotype (
NMSA
)
.
Western Cape
: 6
ơ 14^‘
S Africa
:
Cape
#21 /
70km
E of Laingsburg
/
33°06'S
:
21°35'E
500m
/
Date
:
24.xi.1990
/
Whittington
&
Londt
/
Dry Dwyka River
area’ (
NMSA
,
BMNH 1
ơ 1^)
.
Other specimens examined:
NAMIBIA
: 2
ơ 1^‘
Gt
Karas
Mtns
[Groot-Karasberge,
27°20'S
:
18°45'E
] / SWA /
SA Museum’
~ ‘
Mus. Staff
/
Nov 1936
(1939
^)
’ (
SAMC
)
;
2
ơ 2^‘
Gt. Fish
R. /
Aiais
[
27°55'S
:
17°29'E
], S.
W.A.
’ ~ ‘
Mus. Staff
/
Nov. 1936
’ (
SAMC
)
.
SOUTH AFRICA
: 4
ơ 6^‘
26 mls [
c
.
41 km
]
North
/ of
Postmasburg
[
28°19'S
:
23°04'E
]’ ~ ‘
Mus. Staff
/
Oct.1939
’ (
SAMC
)
;
1
ơ 4^‘
Kenhardt
[
29°30'S
:
21°00'E
] /
Area’
~ ‘
Mus. Staff
/
Oct. 1939
’ (
SAMC
)
;
5
ơ 4^‘
South Africa
: N
Cape
/
1 km
S Carnarvon
1260m
/
Appie
van
Heerden Nat.
/
Reserve
14.xi.2008
/
30°58.83'S
:
22°07.39'E
/
J&A Londt Karoo
scrub’ (
NMSA
)
;
1
ơ
‘S
Africa
:
Cape
#34 /
2km
N of Middelpos
/
31°54'S
:
20°14'E
1250m
/
Date
:
29.xi.1990
/
Londt
&
Whittington
/
Dry
scrub on dam bank’ (
NMSA
)
;
3
ơ 3^‘
South Africa
: N
Cape
/
Fish River
bridge
23 km
/ SE
Middelpos
1145 m
/
32°01.42'S
:
20°24.41'E
/
18.xi.2008
J&A Londt
/
Sandy
riverine scrub area’ (
NMSA
)
;
2
ơ 1^‘
S.W. Africa
: /
Cape
of
Good Hope
, /
Nels Poort.
[Research Station,
32°07'S
:
23°00'E
] /
2.xii.1933
. /
J. Ogilvie’
(
BMNH
)
;
1^‘
S.W. Africa
: /
Cape
of
Good Hope
, /
Nels Poort.
/
4.xii.1933
. /
J. Ogilvie’
(
BMNH
)
;
5
ơ 2^‘
Sth Africa
:
Cape
Prov
/
Gamka River
40km
N /
Prince Albert
3321BB /
11.xi.1986
500m
/
Londt
&
Quickelberge
/
Sandy area
/
Acacias’
(
NMSA
)
;
1
ơ 1^‘
Gamkas Poort
[
33°19'S
:
21°43'E
] /
Oct 1937
’ (
SAMC
)
;
1
ơ
‘
Cape Province
/
43km
ENE of Ceres
[
33°22'S
:
19°19'E
] on / road to
Sutherland
/
2-3.xii.1989
/
F.W. & S.K. Gess’
(
AMGS
)
.
Distribution, phenology and biology: A fairly widely distributed species found in the Succulent Karoo and Nama-Karoo biomes of southern Africa (
Fig. 43
). Adults have been collected during spring and summer (October–December) (Table 1). Experience tells me that the species is found in fairly arid, sandy places and that population densities may be low.
Similar species: This species is similar to
nilicola
and
xeromyia
.