Cryptic species in the nuisance midge Polypedilum nubifer (Skuse) (Diptera: Chironomidae) and the status of Tripedilum Kieffer
Author
Cranston, Peter S.
Author
Martin, Jon
Author
Spies, Martin
text
Zootaxa
2016
2016-02-15
4079
4
429
447
journal article
31508
10.11646/zootaxa.4079.4.3
9e67a942-2592-41d5-a7e2-b7771e20ba9e
1175-5326
1050863
4F1CC4B7-2A6F-4BB6-8F05-00650BDB001A
Polypedilum quasinubifer
Cranston
sp. n.
(
Figs 1A, C, F
; 2C, F; 3C; 4B, D, F; 5B)
urn:lsid:zoobank.org:act:70DEF8F7-C4A2-445B-8550-B8417
B29393
F
Type
material.
Holotype
,
Le
/
Pe
/
♂
,
AUSTRALIA
:
Queensland
,
Lawn Hill National Park
,
Musselbrook
,
Amphitheatre
,
18°21’S
138°09'E
,
13.v.1995
(
Cranston
) (
ANIC
).
Paratypes
, Le/Pe/
♂
, Le/Pe/
♀
, as
Holotype
; Pe,
Queensland
, Lawn Hill N.P., Musselbrook, Border Pool,
18°36’53”S
137°59’25”'E,
14.v.1995
(
Cranston
) (
ANIC
).
Other
material examined
.
SINGAPORE
:
Upper Seletar Reservoir
,
1°24’10"N
103°48'27"E
,
29.vii.2012
,
16.vii.2013
,
8.x.2013
(
NUS team
) (all life stages);
Bedok Reservoir
,
1°20’47”N
103°55’31”E
,
11.ix.2013
, (
NUS team)
(all life stages) (some of each stage to
ANIC
, remainder to
RMBR—MV
)
.
THAILAND
: single L from each of:
Chiang Mai
,
Amphur Doi Saket
,
Nam Kuang
,
19°00’N
99°17’E
,
15.v.
2004
,
554 m.
,
L-689 (
Vitheepradit & Prommi
);
Mae Kuang
,
19°00’N
99°17’E
,
15.v.2004
(
DuCharme
)
Kalasin
, Amphur Khao Wong, Tad Tong Waterfall,
16°45’N
104°07’E
,
204 m
.
, TH62 (
Vitheepradit
); Petchabun, Khao Khor N.P., stream from Tamtip Waterfall, 16°39.594’N 101°07.901’E,
182 m
.,
11.v.2004
, L-678, TH5 (
Vitheepradit & Prommi
);
Chaiyaphum
,
Phu Kiew WS
,
Lam Num Prom
,
16°27’N
101°39’E
,
589 m
.
,
2.v.2004
(
DuCharme
)
;
Prachin Buri
,
Khao Yai N.P.
,
Kaeng Wang Thong
,
14°10.077’N
101°43.420’E
(
Sites & Vitheepradit
) (all
ANIC
)
.
Description.
Adults (
Figs 1A, C, F
,
2C
,
3B
). For mensural features see
Table 1
. Frontal tubercles very small, 8–10 µm long. Foretibial apex triangularly tapering without apical spine (
Fig. 1C
). Pulvillus (
Fig. 5B
) divided in 2 parts; outer plumose but not forming ‘pad’, extending to mid-claw; inner part simple, unbranched, subequal in length to outer; empodium sparsely plumose, extending beyond pulvillus apex. Wing pattern very faint on (teneral)
type
specimens, variably to strongly developed on those from
Singapore
(
Fig. 1A
). Male T VIII waisted (tapering anteriorly); TIX with cluster of setae not lying within delimited paler area; anal point narrow. Male genitalia (
Fig. 1F
) with conventional gonocoxite and slender gonostylus tapering to blunt apex. Superior volsella curved, shorter and stouter than in
P. nubifer
, bearing dorsolateral seta inserted at about 2/3 length of volsella. Inferior volsella slender, with apical seta arising from weakly bilobed apex, scarcely longer than any other in sparse cluster of setae. Female genitalia: gonocoxite IX with 7–11 setae. Lobes of gonapophysis VIII (
Fig. 2C
): ventrolateral lobe squat (15–20 µm) bearing short setae; dorsomedial lobe no more than a rounded microtrichiose contour without setae, c.
90 x
125 µm, rounded rectangular.
Pupa (
Figs 2F
,
3C
). Exuviae 5.0–
5.5 mm
long, pale with yellow highlights and yellow-brown comb on abdominal segment VIII. Cephalic tubercles triangular, 25–35 µm long and about equally wide at base, bearing 40– 55 µm long frontal seta inserted basally on tubercle. Thoracic horn plumose, arising from oval, golden basal ring. Thorax mid-dorsally with dense cluster of small tubercles. Abdominal tergite spine/spinule pattern and setation as in
Fig. 3C
. Hook row on segment II c. 45–50% of tergite width, with c. 30–42 hooklets. Caudolateral spur on VIII (
Figs 2F
,
3E
) well-developed, with dominant (apical-most) spine and few significantly smaller subsidiary spines not extending to L4 setal base. Anal lobe fringe evenly uniserial, with 23–30 taeniae, without dorsal seta.
Larva (
Fig. 4B, D, F
). For mensural features see
Table 2
. Head yellow, with pale postmentum and narrow dark occipital margin; head total length, postmentum, mentum (
Fig. 4D
) and mandible c. 30–40% shorter than in
P. nubifer
. Antennal segment lengths shorter but ratios similar: Antennal blade relatively longer, reaching antennal apex (
Fig. 4B
). Microsculpture of ventromental plate (
Fig. 4F
): with sparser striae, terminating anteriorly on outer (lateralmost) corner of plate in 3–4 shallow lobes.
Notes.
Polypedilum quasinubifer
is smaller in all measurements (e.g. wing length c. 40% of
P. nubifer
/
paranubifer
, has fewer setae, and differs significantly in ratios, notably the fore leg ratio of 1.9–2.2 (in both sexes). The pupa is smaller and paler than those of
P. nubifer
/
paranubifer
), with smaller cephalic tubercles but longer frontal setae arising nearer the tubercle base. The thorax has a dorsal cluster of small tubercles (rather than aligned rows of larger tubercles). The hook row is narrower (no more than 50% of tergite width) and with fewer hooklets. The 'comb' on segment VIII is paler, smaller, with a more dominant major spine and fewer subsidiary spines. The anal lobe has fewer taeniae (<30) in a uniform uniserial row.