Diestostemma rubriventris ( Schmidt, 1928 )

Pinto, Ângelo Parise, Mejdalani, Gabriel & Takiya, Daniela Maeda, 2017, Unraveling the white-clothed Diestostemma Amyot & Serville: a taxonomic revision of the American sharpshooters of the D. bituberculatum complex (Hemiptera: Cicadellidae), Zootaxa 4281 (1), pp. 135-164 : 157-159

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) .

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.

Figures

FIGURE 93. Map of northern South America with distribution records of the Diestostemma bituberculatum species complex. Colored areas correspond to the Neotropical regionalization of biotic elements by Morrone (2014). Abbreviations: OR, Orellana Province, Ecuador; MDD, Madre de Dios Department, Peru; AM, Amazonas, RO, Rondônia, and MT, Mato Grosso, for Brazilian States.

FIGURES 31 – 36. Female habitus of species of the Diestostemma bituberculatum complex in dorsal (31, 33, 35) and lateral (32, 34, 36) views. 31 – 32. Paratype of D. gervasioi sp. nov. (Ecuador, Orellana Province, USNM); 33 – 34. Paratype of D. olivia sp. nov. (Ecuador, Orellana Province, USNM); 35 – 36. D. rubriventris (Schmidt, 1928) (Peru, Madre de Dios Department, DZRJ). Scale bars = 5 mm.

FIGURES 37 – 45. Habitus of males (37, 39, 41, 43) and females (38, 40, 42, 44 – 45) of the Diestostemma bituberculatum species complex in ventral view. 37 – 38. Holotype and paratype of D. albinoi sp. nov. (Ecuador, Orellana Province, EPNC, USNM); 39 – 40. D. bituberculatum (Signoret, 1855) (French Guiana, Cayenne Arrondissement, INHS, DZRJ); 41 – 42. Holotype and paratype of D. olivia sp. nov. (Ecuador, Orellana Province, EPNC, USNM); 43 – 44. Holotype and paratype of D. gervasioi sp. nov. (Ecuador, Orellana Province, EPNC, USNM); 45. D. rubriventris (Schmidt, 1928) (Peru, Madre de Dios Department, DZRJ). Scale bars = 5 mm.

FIGURES 46 – 55. Diagrammatic representation of the sclerotized dark vein (SDV) areas of forewings of males (46, 48, 50, 52) and females (47, 49, 51, 53 – 55) of the Diestostemma bituberculatum species complex in dorsal view. 46 – 47. D. albinoi sp. nov.; 48 – 49. D. bituberculatum (Signoret, 1855); 50 – 51. D. gervasioi sp. nov.; 52 – 53. D. olivia sp. nov.; 54 – 55. D. rubriventris (Schmidt, 1928). Abbreviations: AM = anal margin; CM = costal margin; CS = claval suture.

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.

FIGURES 25 – 30. Female habitus of species of the Diestostemma bituberculatum complex in dorsal (25, 27, 29) and lateral (26, 28, 30) views. 25 – 26. Paratype of D. albinoi sp. nov. (Ecuador, Orellana Province, USNM); 27 – 28. D. bituberculatum (Signoret, 1855) (French Guiana, Cayenne Arrondissement, DZRJ); 29 – 30. Paratype of D. cavichiolii sp. nov. (Brazil, Mato Grosso State, DZUP). Scale bars = 5 mm.

FIGURES 15 – 24. Male habitus of species of the Diestostemma bituberculatum complex in dorsal (15, 17, 19, 21, 23) and lateral (16, 18, 20, 22, 24) views. 15 – 16. Holotype of D. albinoi sp. nov. (Ecuador, Orellana province, EPNC / USNM); 17 – 18. D. bituberculatum (Signoret, 1855) (French Guiana, Cayenne Arrondissement, INHS); 19 – 20. Holotype of D. cavichiolii sp. nov. (Brazil, Mato Grosso State, DZUP); 21 – 22. Holotype of D. gervasioi sp. nov. (Ecuador, Orellana Province, EPNC / USNM); 23 – 24. Holotype of D. olivia sp. nov. (Ecuador, Orellana Province, EPNC / USNM). Scale bars = 5 mm.