Review of the leafhopper genus Drabescus Stål (Hemiptera: Cicadellidae: Deltocephalinae) in the Indian subcontinent with description of one new species
Author
Viraktamath, C. A.
0000-0002-7402-3841
Department of Entomology, University of Agricultural Sciences, GKVK, Bengaluru 560065, India.
chandrashekara.viraktamath@gmail.com
Author
Webb, M. D.
0000-0002-1312-6142
Department of Life Science, The Natural History Museum, Cromwell Road, London SW 7 5 BD, United Kingdom. & m. webb @ nhm. ac. uk; https: // orcid. org / 0000 - 0002 - 1312 - 6142
m.webb@nhm.ac.uk
Author
Yeshwanth, H. M.
0000-0002-7402-3841
Department of Entomology, University of Agricultural Sciences, GKVK, Bengaluru 560065, India. & hmyeshwanth @ gmail. com; https: // orcid. org / 0000 - 0002 - 5104 - 3401
chandrashekara.viraktamath@gmail.com
text
Zootaxa
2022
2022-04-20
5128
2
225
247
journal article
55847
10.11646/zootaxa.5128.2.4
a9b6e575-57e1-4fe3-90ee-c4a375f2958e
1175-5326
6479814
5C65C12C-7943-47C8-B08E-01B84B4B0ED0
Drabescus angulatus
Signoret
Figs 1A–D, 2G, 3AB, 5A, 6A–F.
Drabescus angulatus
Signoret 1880: 210
(120), plate 7, fig. 73;
Distant 1908: 305–306
, fig. 194;
Ghauri 1964: 688
;
Zhang & Webb 1996: 24
, figs 380–384, 525.
Greenish yellow with rich dark brown maculation on crown, pronotum and exposed mesonotum, some of these maculae coalesce to form irregular lines. Crown fore margin with transverse yellowish ochraceous band with dorsal and ventral dark brown margins. Eyes dark reddish brown with median transverse band in continuation of fore marginal transverse band. Face reddish brown with dark brown clypellus and dark brown maculae or entirely dark brown with outer margins of genae paler.Antennae with scape and pedicel dark brown with apices and arista reddish ochraceous brown. Forewings hyaline with brownish tinge, with dark brown maculation on forewings with a median transverse hyaline band more prominent in darker specimen (
paratype
male) compared to lighter one (
holotype
male); appendix and apical angels dark brownish; veins dark brown spotted with yellowish white.
Crown medially slightly longer than next to eyes, transversely depressed across eyes, about 5.5× as wide between eyes as median length, transition to face angulate and carinate, not rimmed. Pronotum 2.5–2.75× as wide as long medially. Fore tibia lamellately expanded.
Male genitalia
. Pygofer about twice as long as height at base in lateral view, broad in basal 0.33 and then narrowed posteriorly terminated by spine-like process arising from ventral margin, dorsoposterior angle rounded. Valve with posterior margin convexly rounded about 2.4× as wide as long. Subgenital plates triangular, about 2.2× as long as wide at base; apices narrowed to form un-pigmented appendage. Style elongate, with poorly developed subapical lobe, apophysis long, slightly curved laterally and transversely striate. Connective with stem shorter than arms, distally bifid, anterior margin with prominent median lobe. Aedeagus V-shaped in lateral view, dorsal apodeme almost as long as shaft, basal processes on lateral side about as long as shaft and slightly curved in distal half in lateral view, in dorsal view apices convergent; shaft slightly broader at base and slightly narrowed in lateral view, in dorsal view with lateral marginal lamellate expansions right from base and extending to distal 0.75 shaft length as they narrow; gonopore subapical on ventral surface.
Female pregenital sternite
. Sternite VII slightly longer medially than VI, posterior margin concave with a median U-shaped excavation (
Fig. 2G
).
Measurements
. Male
8.1–8.2 mm
long, 2.8–3.0 mm wide across eyes and
2.6–2.8 mm
wide across posterolateral angles of pronotum. Female
8.2–8.4 mm
long,
2.7–2.9 mm
wide across eyes and
2.4–2.6 mm
wide across posterolateral angles of pronotum
Material examined.
INDIA
:
1♂
,
Himachal Pradesh
,
Bandrol
,
18.v.2016
,
Stuti
(
NPC
)
;
1♂
,:
Solan
,
30.vii.2006
, NPIB (
UASB
)
;
1♀
,
Jammu
&
Kashmir
:
Sri Nagar
,
3.x.1981
,
Dworakowska
;
1♀
,
Mizoram
:
Lunglei
,
20.xi.1981
,
C.S. Wesley
(
BMNH
)
.
PAKISTAN
:
1 ♂
,
Abbottabad
,
15.vi.1963
,
on
Asparagus
(BMNH)
.
FUGURES 1 A–L.
Species of
Drabescus
from Indian subcontinent. Habitus, dorsal and lateral views. A–D,
D. angulatus
Signoret
: male from Bandrol (A–B) and female from Srinagar (C–D); E–F,
D. austroindicus
sp. nov
.
; G–J,
D. kempi
Pruthi
, male (G–H) and female (I–J); K–L,
D. limbaticeps
Signoret.
FIGURES 2 A–L.
Species of
Drabescus
from Indian subcontinent. Habitus, dorsal and lateral views (A–F) and female sternite VII (G–L). A–B,
D. nervosopunctatus
Signoret
; C–D,
D. nigrofacialis
(Distant)
; E–F,
D. shillongensis
Rao
; G,
D. angulatus
Signoret
; H,
D. kempi
Pruthi
; I,
D. limbaticeps
Signoret
; J,
D. nervosopunctatus
Signoret
; K,
D. nigrofacialis
(Distant)
; L,
D. shillongensis
Rao.
FIGURES 3 A–I.
Species of
Drabescus
from Indian subcontinent, faces. A–B,
D. angulatus
Signoret
male (A) and female (B); C,
D. austroindicus
sp. nov
.
; D–E,
D. kempi
Pruthi
, male (D) and female (E); F,
D. limbaticeps
Signoret
; G,
D. nervosopunctatus
Signoret
; H,
D. nigrofacialis
(Distant)
; I,
D. shillongensis
Rao
, male.
FIGURES 4 A–G.
Species of
Drabescus
from Indian subcontinent.
D. stramineus
Distant
, lectotype female: A, dorsal view; B, lateral view; C, face and thoracic sternites, ventral view; D, abdomen ventral view; E, data labels; F.
Drabescus
sp.
, nymph; G.
D. limbaticephs
(Stål)
, adult in natural habitat.
FIGURE 5 A–G.
Species of
Drabescus
from Indian subcontinent, forelegs, front view. A,
D. angulatus
Signoret
; B,
D. austroindicus
sp. nov
.
; C,
D. limbaticeps
(Stål)
; D,
D. kempi
Pruthi
, male; E,
D. nervosopunctatus
Signoret
; F,
D. nigrofacialis
(Distant)
; G,
D. shillongensis
Rao
, male.
FIGURES 6 A–F.
Drabescus angulatus
Signoret
, male genitalia. A, pygofer and anal tube, lateral view; B, valve and subgenital plates, dorsal view; C, style and connective, dorsal view; D, aedeagus, lateral view; E–F, aedeagus, dorsal and ventral views.
Remarks
. This species was described from an unknown number of female specimens (
syntype
(s)) with the following data: “Indes nord” in “coll. Signoret”. A type was examined by
Zhang & Webb 1996: 25
and designated as
lectotype
. Colouration of this species is very variable. This species can easily be recognized among the species of the Indian subcontinent by the following combination of characters: male pygofer strongly and abruptly narrowed in basal 0.4 and then gradually narrowed in lateral view, about 2× as long as basal width; style almost linear and the basal processes of the aedeagus slightly shorter than the shaft in both ventral and posterior views and their apices convergent apically; female sternite VII with posterior margin concave and medially with U-shaped excavation.
Ghauri (1964)
was the first to record this species from
Pakistan
. Two females from Mizoram, Lunglei (BMNH) are externally similar to this species but have a pronounced medial longitudinal yellow band on the pronotum and mesonotum and the oblique posterior margin of the pregenital sternite either side of midline straight rather than sinuate.