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 curtus
(
Wiedemann, 1819
)
Figs 2
,
17, 18
,
43
Dasypogon curtus
:
Wiedemann 1819: 6
; 1821: 229; 1828: 409.
Dasypogon
(
Acnephalum
)
curtus
: Walker 1854: 458
.
Acnephalum curtus
: Loew 1860: 72
.
Sisyrnodytes curtus
:
Schiner 1866: 680
;
Oldroyd 1957: 84–85
; 1974: 74; 1980: 368 (catalogue).
Dasypogon luscinius
Walker, 1849: 360
.
Syn. n.
Sisyrnodytes luscinius
:
Oldroyd 1957: 85–86
; 1974: 72; 1980: 368 (catalogue).
Redescription:
Female
(based on
holotype
in fair condition, left mesothoracic leg broken off beyond femur, left metathoracic leg missing terminal four tarsomeres, thorax badly cracked dorsoventrally on left side with resulting damage to pleura, mesonotum and scutellum, left haltere missing it’s knob).
Head
: Dark red-brown to black, white, pale yellow and red-brown setose. Antennae: Red-brown except for tip of style which is yellowish. Scape and pedicel mostly pale yellowish setose. Major ventral setae of pedicel not projecting beyond level achieved by postpedicel (setae probably damaged). Basal element of style short (about as long as broad). Eye to face width ratio 1.6:1. Mystax moderately developed, predominantly white except for ventral setae which are dark red-brown. Frons and vertex white setose. Laterally situated frontal setae not extending below antennal sockets. Occipital setae white, postoculars mostly dark red-brown. Palps dark red-brown setose, proboscis white setose.
Thorax
: Dark red-brown. Pronotum white setose. Mesonotum entirely setose except for narrow paramedial strips, sutural and postsutural spots. Lateral macrosetae red-brown (
npl
&
sal
) and pale yellow (
pal
), other setae mostly white (there are a few pale brownish ones). Scutellum apruinose, somewhat inflated, with poorly defined transverse groove; disc asetose, 16 apical setae ranging from orange-brown (laterally) to yellowish (medially). Pleural setae white. Katepimeron asetose, katatergals long, shafts more or less smooth proximally, wavy distally. Legs: Red-brown, meso- and metathoracic femora orange anteroventrally, metathoracic tibiae mostly orange. Legs mainly white setose, but there are black setae terminally on tibiae and ventrally on tarsi. Claws longish, dark red-brown; empodia short yellowish, pulvilli moderately developed (longer than empodia and about one-third length of claws). Wings 5.2×
2.2 mm
, C white setose basally; membrane weakly pale orange stained basally. Haltere brown-yellow.
Abdomen
: Red-brown; terga partly yellow-white setose (these setae mainly laterally situated, but do extend along posterior margins for a short distance).
Male
: Similar to female.
Genitalia: The terminalia of a male from ‘
7 mi.
N. Vanrhynsdorp’ were excised, macerated and illustrated (
Figs 17, 18
). Epandrium reduced and simple in structure, about twice as long as broad in lateral view. Proctiger fairly short. Gonocoxite with suboval external lobe (in lateral view). Internal lobe fairly robust with small inwardly directed hooked tip. Gonostylus short, simple in structure. Hypandrium fairly robust, suboval in ventral view, constricted at about midlength (in ventral view). Aedeagus fairly robust, blunt tipped.
Variation: Wing length
ơ
3.1–5.2 mm
,
^3.1
–6.2 mm
. A fairly variable species with respect to general body and setal coloration. For example, antennae and mystax may be entirely white setose and occiput may lack yellowish macrosetae. Major ventral setae of pedicel usually extend beyond level attained by postpedicel. Leg coloration varies from orange through to dark red-brown, metathoracic legs often paler than others. Wing staining also varies slightly in both intensity and extent.Abdominal coloration variable from almost entirely orange (parts of T1 always dark red-brown) to almost entirely red-brown (lateral parts of terga invariably paler than medial parts).
Holotype
(examined):
^SOUTH
AFRICA
:
Western Cape
: ‘Cap b. sp. [
Cape
of Good Hope]’, ‘
Sisyrnod
. (
Dasy
). /
curtus
/
Coll. Winthem’
, ‘Type’ [red] (
NHMW
). Note: Wiedemann (1821) recorded the species from ‘Prom. bon. sp’ giving the gender as male and the repository as ‘Mus. Westerm. et n.’.
Oldroyd (1957)
states
‘
Holotype
in Copenhagen Museum’, but Thomas Pape (pers. comm.) reports that the species is not represented in that collection. The only specimen likely to be the type is the NHMW female even though Wiedemann (1821) indicated his material as being male.
Other type material examined:
SOUTH AFRICA
:
^holotype
(
luscinius
) ‘Type’ [circular with green rim], ‘Dr. Smith. / S. Afr. 44–6.’, ‘One of Walkers / series so named. / E A W’, ‘
Holotype
/
Dasypogon
/
luscinius
Walker
/ det. J.E. Chainey. 1983’ [this label has a circular red rimmed label glued to its upper right hand corner reading ‘Holo- / type’] (BMNH). Notes: The
luscinius
^holotype
is double mounted on a cellulose strip. Condition: Poor, head detached and glued to mounting strip, both antennae broken off beyond pedicel. The thorax remains on its mounting pin but all the legs are broken off beyond trochanter; one, probably the right prothoracic leg, is glued to the mounting strip and is complete enough to show the condition of the pulvilli. The right wing is missing while the left wing is dirty and has somewhat ragged edges (approx. measurements are 5.0×2.0 mm). The abdomen is detached and glued to the mounting strip. The specimen is sufficiently well preserved to allow comparisons with other specimens. A well preserved female from ‘Knersvlakte, North of Van Rhynsdorp’ agrees very well with the
holotype
.
Type locality: I here designate the
type
locality as
South Africa
,
Western Cape
,
Table Mountain Nat. Park
,
Olifantsbos
[
34°14.442'S
:
18°23.159'E
]
.
Other specimens examined:
SOUTH AFRICA
: 1
ơ
‘South Africa,
Cape
Prov /
11mi.
[
c
.
18 km
] NNE. Hondeklipbaai /
Sept. 8, 1972
, 3017Ab, / ME&BJ. Irwin,
200 ft.
alt– / Reddish sand, shrubs’ (NMSA); 2
ơ 6^‘
Wallekraal [
30°24'S
:
17°31'E
] / Namaqualand’ ~ ‘Mus., Expd., /
Oct. 1950
’ (SAMC); 1
ơ
‘South Africa,
Cape
Prov /
7mi.
[
c
.
2 km
] N. Vanrhynsdorp /
Sept. 10, 1972
. M.E. Irwin /
400 ft
, 3118Bc, red dunes’ (NMSA);
1^‘
Knersvlakte [
31°15'S
:
18°45'E
] North / of Van Rhynsdorp / South-West
Cape
/
6–9 October 1964
/ B&P Stuckenberg’ (NMSA);
1^‘
S. Afr. C.P. / Koekenaap [Siding,
31°32'S
:
18°17'E
] / Skaapvlei / 28.ix.76 / V.B. Whitehead’ (SAMC); 3
ơ 9^‘
Olifants River [
31°42'S
:
18°12'E
] / bet. Citrusdal & / Clanwilliam C.P.’ ~ ‘Museum Staff /
Oct. – Nov. 1931
’ (SAMC); 1
ơ
‘South Africa C.P. / Doringbaai
31.44S
/
18.14E
17.xi.1984
/ C.D. Eardley’ (SANC);
2^‘
Sth Africa:
Cape
Prov /
34km
N Op die Berg / 3219CC
21.xi.1986
/ Londt & Quickelberge / Sandy area/grass’ (NMSA); 1
ơ
‘
Cape Province
/
11km
W of Clanwilliam [
32°11'S
:
18°54'E
] / on road to Graafwater /
1.xi.1989
/ F.W. & S.K. Gess’ (AMGS);
1^‘
Leipoldtville [
32°13'S
:
18°29'E
] / - Eland’s Bay / C.P.’ ~ ‘Mus., Exp., / Oct., 1947’ (SAMC); 6
ơ 10^‘
Paleisheuwel [
32°28'S
:
18°43'E
] / C.P.’ ~ ‘Mus., Exp., /
Nov. 1948
.’ (SAMC); 1
ơ 2^‘
S Africa:
Cape
#63 /
14km
NNW Citrusdal /
32°31'S
:
18°58'E
300m
/ Date:
1.ix.1991
/ Coll: J.G.H. Londt / Woody plants; sandy’ (NMSA); 6
ơ 10^‘
Citrusdal [
32°35'S
:
19°01'E
] / Distr.’ ~ ‘Mus. Exp. /
Nov. 1948
’ (SAMC); 3
ơ 3^‘
Sth Africa: W
Cape
/ Gonnemanskraal N of / Jacobsbaai JGH Londt /
32°57'14''S
17°53'07''E
/
21–26.xii.2002
0–10m
/ Dune sand & vegetation’ (NMSA);
1^‘
Cape Province
/ Worcester. [
33°39'S
:
19°26'E
] /
January 1929
’, ‘S. Africa. / R.E. Turner. / Brit. Mus. / 1929-96’ (BMNH);
1^‘
Capland / Stellenbosch [
33°56'S
:
18°51'E
] /
25 x 1925
/ Dr. H. Brauns.’ (NMSA); 1
ơ 1^‘
South Africa: W
Cape
/ Good Hope Farm
c
.
35km
/ SW Robertson
380m
/
33°59'13''S
19°36'00''E
/
22–23.x.2005
JGH. Londt /
Protea
,
Dodonaea
fynbos’ (NMSA); 1
ơ
‘Sth Africa:
Cape
Prov /
10km
NE Muizenberg / 3418AB
28.xi.1981
/ B.R. Stuckenberg / Coastal Macchia’ (NMSA); 2
ơ 1^‘
Sth Africa:
Cape
Prov / Brenton on Sea 3423AA /
10.xii.1979
J. Londt / & B. Stuckenberg Dune / & hillside vegetation’ (NMSA); 2
ơ 1^‘
Strandfontein [
34°05'S
:
18°33'E
] / False Bay /
1 Nov. 1960
’ (SAMC);
1^‘
Strandfontein /
March 1950
/ Zinn, Hesse’ (SAMC); 2
ơ 2^‘
South Africa: W
Cape
/ Table Mountain Nat. Park / Silvermine
18.x.2006
100m
/
34°06.994'S
:
018°24.253'E
/ JGH Londt Skildersgatkop / Trail Sandy fynbos area’ (NMSA); 1
ơ 1^‘
S Africa:
Cape
#43 / Kommetjie (Hillside) /
34°09'S
:
18°20'E
30m
/ Date:
1.x.1993
/ Coll: J.G.H. Londt / Macchia: Sandy area’ (NMSA); 6
ơ 4^‘
South Africa: W
Cape
/ Table Mountain Nat. Park / Olifantsbos
16.x.2006
20m
/
34°14.442'S
:
018°23.159'E
/ JGH Londt Sandy hillside / fynbos area with flowers’ (NMSA); 1
ơ 2^‘
South Africa /
Cape
Town - /
Cape
Point [
34°21'S
:
18°29'E
], /
xi.1930
/ H.N. Simmonds’ (BMNH); 1
ơ
‘Still bay. [Stilbaai,
34°23'S
:
21°27'E
] C.P. /
9–12–xi– 1940
/ G. van Son’ (NMSA); 33
ơ 39^‘
Pearly Beach [
34°40'S
:
19°30'E
] / Bredasdorp’ ~ ‘S.A.M. / 12:58 [
xii.1958
]’ (SAMC).
Distribution, phenology and biology: This species is a South African endemic found in the winter-rainfall areas of the
Western Cape Province
(
Fig. 43
). Adults are active from spring to autumn (i.e. September–March (no February record)) (Table 1). Label data indicate that the species is found predominantly in sandy places (e.g. vegetated dunes and similar situations) with fynbos vegetation. Personal experience suggests that individuals rest on open sand in places where there are plants to provide some shade and protection from wind, and that population levels may be locally fairly high.
Similar species: This species is distinctive and not easily confused with others. The pulvilli are not minute, and although small (almost as long as the empodia and about one third the length of claws), are distinct.