A review of Afrotropical Ancylorhynchus Berthold, 1827 (Diptera: Asilidae: Stenopogoninae)
Author
Londt, Jason G. H.
text
African Invertebrates
2011
2011-12-31
52
2
471
471
http://www.bioone.org/doi/abs/10.5733/afin.052.0214
journal article
10.5733/afin.052.0214
2305-2562
7917250
Ancylorhynchus gessi
sp. n.
Figs 9
,
39
,
84–86
Etymology: Named for Dr Fred Gess (AMGS), who, together with his wife Sarah, collected many interesting Afrotropical
Asilidae
, including the
holotype
and a
paratype
of this new species.
Description:
Male
(based on
holotype
. Condition: Excellent; slightly greasy.).
Head
: Blackish, silver-grey pruinose, pale yellow to whitish setose. Antenna (
Fig. 9
): Scape and pedicel blackish, whitish setose, postpedicel orange-brown proximally becoming dark red-brown distally, terminal stylus ‘segment’ present, dark red-brown tipped with pit-enclosed spine-like sensory element. Segmental ratios: 1:0.4:4.5:0.3. Face black, uniformly silver-grey pruinose (slightly weaker laterally on epistomal margin), mystax shiny whitish occupying entire facial profile. Frons and vertex black, fine silver-grey pruinose, pale yellow whitish setose; ocellar tubercle fine pale yellow setose. Occiput black, uniformly silver pruinose, pale yellow to whitish setose. Palpus dark red-brown, whitish setose, terminal palpomere swollen, apex with terminal sensory pit. Proboscis dark red-brown, whitish setose.
Thorax
: Black with orange areas dorsally, fine silver-grey pruinose, white and pale yellowish setose. Prothorax entirely blackish, fine silver-grey pruinose, pale yellow-white setose. Mesonotum black except for orange postpronotal lobes and posterolateral regions from just anterior of transverse suture to posterior margin (including postalar lobes), fine silver pruinose, fine moderately long white and pale yellow setose. Mesonotal macrosetae (translucent pale yellow when present): few
dc
confined to posterior region, 2
npl
, 1
spal
, 3
pal
. Scutellum entirely dark red-brown to black, fine silver pruinose, disc sparsely pale yellow setose, hind margin with 4 pale yellow weakly developed macrosetae accompanied by minor setae. Pleura entirely blackish, entirely silver-grey pruinose, setae white to pale yellow confined to
anepst
,
kepst
and
ktg
.
Anatg
and
mes pnot
black. Legs:
cx
dark red-brown to black, silver pruinose, white setose;
tro
dark red-brown;
fem
orange with dark red-brown ventral parts,
tib
yellowish with dark red-brown ventral parts (
tib
3 almost entirely dark red-brown),
tar
uniformly dark red-brown; legs entirely pale yellowish white setose, claws dark red-brown with red-brown proximal parts. Wings (
Fig. 39
): 9.2×
3.4 mm
. Veins orange-brown to dark red-brown. Membrane extensively microtrichose (some proximal cells partly bare), distal cells brown (from about first fork of Rs), slightly orange stained basally and anteriorly and some centrally situated veins bordered by light brownish stain, cells mostly transparent. Haltere orange, slightly darker basally.
Abdomen
: Predominantly blackish with orange to brown-orange patches, fine silver-grey pruinose, pale yellowish white setose. T1 predominantly orange with broad dark red-brown medial area; T2–3 blackish with large orange patches posterolaterally; T4–5 blackish with small brown-orange patches posterolaterally. Sternites similar to tergites but orange areas extensive and along posterior margins.
Genitalia
(
Figs 84–86
): Large and bulbous.
Epand
bifid, bulbous, forming pair of relatively large, well-developed, distally down-curved, stout lobes. Lobes closely associated proximally, each having fairly straight appearance in dorsal view, distal parts not inwardly directed, but laterally compressed and ventrally directed.
Proct
simple, projecting beyond
epand
in dorsal view, dorsally situated
cerc
appearing fused posteromedially.
Goncx
relatively poorly developed, distal end somewhat truncate, lacking posteriorly directed terminal process and dorsal finger-like process; inner lobe relatively weakly developed, slender, straight.
Gonst
slightly laterally compressed, posteriorly directed, tip relatively straight.
Hypd
large, well developed, cup-shaped; proximal margin broad, slightly indented medially; distal end smoothly and broadly rounded with some small mediodistal corrugations.
Aed
hidden from view in undissected genitalia.
Female
(topotypic female
paratype
): Similar to male. Head more yellowish setose and gold pruinose. Antennae orange except for dark red-brown stylus. Orange parts of mesonotum more extensive (black area confined to a somewhat cross-shaped central marking that fails to reach posterior margin). Pleura partly orange (posterior part of
anepst
and entire
ktg
). Legs almost entirely orange (except for dark red-brown
cx
and terminal tarsomeres). Wing: 10.5×4.0 mm (slightly larger than
♂
).
Variation: A species displaying little individual variation of note.
Holotype
:
♂
NAMIBIA
: ‘in cop’, ‘
Namibia
,
N of Kalkveld
/ on road to
Otjiwarongo
/
20.50S
16.13E
/
25.iii.1997
/
F.W. & S.K. Gess’
(
AMGS
).
Paratypes
:
2♂
1♀
NAMIBIA
:
1♂
‘
Kaoko Otavi
[
18°18'S
:
13°42'E
] / S.
W.A.
’ ~ ‘
Mus. Exped.
/
Mar. 1926
’ (
SAMC
)
;
1♂
1♀
‘
Kamanyab
[waterhole,
19°48'S
:
14°50'E
] / S.
W.A.
’ ~ ‘
Mus. Exped.
/
Mar. 1925
’ (
SAMC
)
;
1♀
same data as holotype (
AMGS
)
.
Distribution, phenology and biology: Known only from
Namibia
(
Table 1
). Adults have been collected only in March (Table 2). The biology is unknown, but localities are dominated by the Savanna biome.
Similar species: A member of the
reynaudii
species-group with close similarities to
whiteheadi
.