Unraveling the white-clothed Diestostemma Amyot & Serville: a taxonomic revision of the American sharpshooters of the D. bituberculatum complex (Hemiptera: Cicadellidae)
Author
Pinto, Ângelo Parise
Author
Mejdalani, Gabriel
Author
Takiya, Daniela Maeda
text
Zootaxa
2017
4281
1
135
164
journal article
28697
10.11646/zootaxa.4281.1.14
da5b3047-b669-4276-89ef-69ecf31d33ff
1175-5326
816007
DE0BD9D9-B661-43DF-90BA-4F31C4B3ADC9
Diestostemma rubriventris
(
Schmidt, 1928
)
LSID http://zoobank.org/urn:lsid:zoobank.org:act:B042E769-5367-4215-BC9B-8842A6D88600 (
Figures 35–36
,
45
,
54–55
,
92–93
)
Leucopepla rubriventris
Schmidt, 1928
: 37
–38 (description of female
holotype
from
Cuiabá
,
Mato Grosso
,
Brazil
in
MZPW
, comparison with
D. bituberculatum
);—
Metcalf (1965: 470, catalog)
;—
Young & Nast (1963: 269, invalid subsequent designation of the female
holotype
as
lectotype
)
;
Diestostemma rubriventris
(
Schmidt, 1928
)
:—
Young (1968: 32–33, comb. nov., note on the sternite VII of the female lectotype [holotype], record from Peru [sic!])
;—
McKamey (2007
: 289, catalog, records from Brazil and Peru based on
Metcalf 1965
and
Young 1968
).
Material examined (
1
♀
).
PERU
.
[
Madre de
Dios Region
:
Tambopata Province
,
Tambopata National Reserve
],
Rio Tambopata
,
Explorer’s Inn
,
Rio Tower
(
12°50’12.48”S
,
69°17’36.18”W
, [
205 m
a.s.l.
]),
10.XII.2003
,
Svenson
leg. (
DZRJ
)
.
FIGURES 87–92.
Female sternite VII of species of the
Diestostemma bituberculatum
complex
in ventral view. 87. Paratype of
D. albinoi
sp. nov.
(Ecuador, Orellana Province, USNM); 88.
D. bituberculatum
(French Guiana, Cayenne Arrondissement, DZRJ); 89. Paratype of
D. cavichiolii
sp. nov.
(Brazil, Mato Grosso State, DZUP); 90. Paratype of
D. gervasioi
sp. nov.
(Ecuador, Orellana Province, USNM); 91. Paratype of
D. olivia
sp. nov.
(Ecuador, Orellana Province, USNM); 92.
D. rubriventris
(Schmidt, 1928)
(Peru, Madre de Dios Department, DZRJ). Scale bars = 1 mm.
Type
repository.
Holotype
female by monotypy in
MZPW
, examined by photos (
Wilson
et al.
2009
[2015]).
Measurements (mm, n = 1).
Total length (from anterior of head to tip of forewings) 20.7; crown length 2.4; transocular distance 3.8; interocular distance 2.7; distance between compound eye and mesal line 1.3; distance between ocellus and mesal line 0.9; pronotal disc maximum width 4.9; pronotal disc maximum length 3.9; forewing length 16.9; metathoracic femur length 4.0; metathoracic tibia length 7.7.
Diagnosis.
A large, dorsolaterally white and ventrally realgar colored
Diestostemma
with two pronotal humps and small dark areas on the forewing. This species has the pronotal humps strongly projected and can be further distinguished from other species of the
D. bituberculatum
complex by the distal SDV rounded (
Figs. 35–36
,
54–55
; usually H-shaped in other
D. bituberculatum
species complex,
Figs. 25–34
,
46–53
), slightly more distally located at about proximal 0.33 (
Figs. 35–36
; around
0.25 in
other
D. bituberculatum
species complex,
Figs. 15–34
) and posterior margin of sternite VII of females bilobed, almost straight mesally (
Fig. 92
; trilobed in
D. albinoi
sp. nov.
,
D. bituberculatum
, and
D. olivia
sp. nov.
,
Figs. 87–88, 91
). The shape of the female sternite VII is very similar to those of
D. cavichiolii
sp. nov.
and
D. gervasioi
sp. nov.
In addition to the diagnostic characters discussed above under these species, the longer sternite VII with ratio between maximum width and mesal length of 1.3 will distinguish
D. rubriventris
from these two species (ratio of ±
1.5 in
D. cavichiolii
sp. nov.
and
D. gervasioi
sp. nov.
).
Distribution.
Known from the
type
locality in the Brazilian Cerrado in
Mato Grosso
State and from the Peruvian Amazonian Forest (
Fig. 93
).
Etymology.
The specific name
rubriventris
in combination with
Diestostemma
to form the taxon name
Diestostemma rubriventris
(
Schmidt, 1928
)
is a noun in apposition. It is formed by the Latin words
venter
(noun m., 3rd decl.; stomach, belly) and
ruber
(adjective; red). This compound word was formed by the stem
rubr-
plus termination
-is
in its genitive singular neuter form plus the noun
ventris
in genitive singular. The name means red abdomen. Based on its etymology, it is clear that the words agreement is between
ruber
and
venter
, instead of with
Diestostemma
. Consequently, the original spelling
rubriventris
(
Schmidt 1928, p. 37
) is correct and should not be affected by the generic combination. A red arsenic (realgar) colored abdomen is a common characteristic among some species of the
D. bituberculatum
complex.
Remarks.
Schmidt (1928, p. 37)
described
Leucopepla rubriventris
very likely based on a single female from Cuiabá municipality, Mato Grosso State, in the Brazilian Cerrado, deposited in the Stettin Museum (currently MZPW). Our specimen agrees very well with the original description and images from this type specimen (
Wilson
et al.
2009
[2015]; images E001271 and E001272), except for a less rounded spot (SDV area) on forewing (
Figs. 54–55
) and the four rounded pale spots (callosities) on the anterior portion of the pronotum (
Figs. 35–36
).
In the original description,
Schmidt (1928, p.
3 7–38
)
described only female characters and mentioned that the male was unknown. Additionally, he provided a single measurement rather than a range as given for other species in the same work (including cases where multiple specimens of a single sex were examined; e.g.,
Homoscarta boliviana
Schmidt, 1928
), indicating that
Schmidt (1928)
based his description of this species on a single female, which we interpret as the holotype by monotypy (ICZN 1999, art. 73.1.2). Based on this interpretation, subsequent nomenclatural acts designating this specimen as lectotype (
Young & Nast 1963
, p. 269;
Young 1968
, p. 32) are invalid. Therefore, the female from Brazil, Mato Grosso State, housed in MZPW, whose labels were transcribed by
Young & Nast (1963, p. 269)
, should be recognized as the holotype.
In the original description,
Schmidt (1928, p. 38)
noted the strong resemblance of his new species with
D. bituberculatum
, from which he distinguished it by the following features: (1) posterior margin of forewings blackish (“...Vorderflügelhinterrand bei der neuen Art geschwärzt...”) versus forewings partially black in
D. bituberculatum
; (2) sclerotized dark veins on forewings as a large rounded black spot located at the end of the basal third (“...ein größerer runder schwarzer Fleck befindet sich um Schluß des Basaldrittels...”) versus an H-shaped marking at the end of basal fourth in
D. bituberculatum
; and (3) posterior margin of sternite VII divided into two lobes (“...hat die neue Art nur 2 Lappen...”) versus trilobed in
D. bituberculatum
(
Fig. 88
, see also
Young 1968
, fig.
21i
). All species in this group have the posterior margin of the forewing dark brown to black, including
D. bituberculatum
. Although the remarkable modified dark vein areas (SDV), often lacking brochossomal coating, on the forewings form distinctive patterns that can be diagnostic at the species-level, they are greatly variable in some species, even among specimens from the same population. The H-shaped marking observed in most specimens of the
D. bituberculatum
complex can be reduced or incomplete, thus they may also exhibit a single spot similar to that observed in the
holotype
of
D. rubriventris
and the specimen herein studied (
Figs. 35–36
). Hence, characters 1 and 2 based on a single specimen are not reliable by themselves. On the other hand, the shape of the posterior margin of the sternite VII has been used as a source of characters for
Proconiini
in many studies (see discussions in
Mejdalani & Silva 2010
and
Dellapé 2015
,
2016
). Differences observed by
Schmidt (1928)
between sternites VII of
D. rubriventris
and
D. bituberculatum
, where “...der Mittellappen ist nicht vorhanden” [the middle lobe is not present] (
Schmidt 1928, p. 38
), may be due to damage of the
holotype
as mentioned by
Young (1968, p. 32)
. Thus, we provide a photo of the sternite VII of this species to confirm Schmidt’s observation (
Fig. 92
).
Nevertheless, the status of
D. rubriventris
remains questionable because males are still unknown and study of specimens from the type locality in Cuiabá is needed. Finally, the occurrence of
D. rubriventris
in Peru, cited by
Young (1968, p. 33)
, is very likely a
lapsus calami
or typographical mistake, considering the author stated that the species “...is known only from the female lectotype [sic]” from Brazil. Therefore, it is herein newly reported from Peru.