Diestostemma cavichiolii, Pinto & Mejdalani & Takiya, 2017

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 : 145-148

Diestostemma cavichiolii sp. nov.

LSID http://zoobank.org/urn:lsid:zoobank.org:act:E1642F7C-9FEC-4FBF-86DC-2CB833354B2E ( Figures 5–6 , 19–20 , 29–30 , 63–65 , 78–80 , 89 , 93 )

Material examined (3 ♂, 7 ♀). Holotype ♂. BRAZIL. Mato Grosso State: Sinop [municipality (11°51’50.40”S, 55°30’14.40”W, 377 m a.s.l.)], X.1975, M. Alvarenga leg. ( DZUP) ; 2 ♀ paratypes, same data as holotype but ( DZUP) ; 1 ♂, 2 ♀ paratypes, same data as holotype but X.1976 ( DZRJ) ; 1 ♂, 1 ♀ paratypes, same data but ( MNRJ) ; 1 ♀ paratype, Vila Vera [nowadays Vera municipality (12°18’21.60”S, 55°19’01.20”W, 372 m a.s.l.)], X.1973, M. Alvarenga leg. ( DZUP) ; Rondônia State: 1 ♀ paratype, [Itapuã do Oeste], FLONA [do] Jamari , light (09°08’45.00”S, 63°00’42.00”W, 112 m a.s.l.), 3–5.IX.2012, R.R. Cavichioli leg. ( DZUP 213687 ).

Measurements of the male holotype (mm). Total length (from anterior of head to tip of forewings) 18.6; crown length 2.4; transocular distance 3.7; interocular distance 2.5; distance between compound eye and mesal line 1.2; distance between ocellus and mesal line 0.7; pronotal disc maximum width 4.5; pronotal disc maximum length 3.7; forewing length 14.7; metathoracic femur length 3.5; metathoracic tibia length 7.2.

Description of the male holotype. Head ( Figs. 5 , 19–20 ). Crown maximum length 0.65 of transocular distance and about same length of interocular distance (ratio of 0.85) in dorsal view; anterior margin rounded with very small convexity at insertion of nymphal blade-like frontal process; epicranial suture indistinct; posterior portion with low M-shaped elevation from ocellar base to posterior margin, connected laterally to strong ridge posterior to ocular suture; frons with deep muscle impressions laterally, median portion flattened, dorsal surface convex; frontogenal suture extending onto crown to ocellar level. Ocellus located at level of anterior limit of compound eye, distinctly closer to eye than mesal line (ratio of distances between ocellus and eye with eye to mesal line 0.31). Epistomal suture indistinct. Clypeus anterior margin slightly higher than level of profile of frons in lateral view.

Thorax ( Figs. 5 , 19–20 ). Pronotum maximum width at posterolateral angles 1.2 times wider than transocular distance; maximum length (at level of humps) 1.6 times longer than crown length; lateral margins slightly convergent anteriorly; disc sculptured dorsally by punctures and callosities, punctures numerous and closer to each other at posterior 0.66; pair of small bean-shaped anterolateral pits posterior to anterior margin, followed by smooth polished elevated area; anteromesal area slightly depressed into rhombus shape bordered by slightly elevated polished areas (callosities); posterior 0.40 dorsally projected into two rounded humps; callosities bordering rhombus with depressed mesal anterior area ill-defined; small mesal callus at posterior margin; posterior margin sinuous with widened, shallow W-shaped outline; dorsolateral carina (dorsopleural carina sensu Young 1968) ill-defined anteriorly, strongly rounded; lateral lobe of pronotum not clearly punctured, with median rounded ridge, posterior margin projected into long forefinger-like process (genus thumb-like process). Mesonotum not punctate, pairs of rounded pits at scutum and rounded processes at division between scutum and scutellum; scutellum with longitudinal carina at about posterior 0.4, but indistinct at posterior portion. Forewing coriaceous (tegmen appearance); surface strongly punctured, punctures minute at distal area; venation sclerotized and moderately elevated at posterior 0.5 of corium, reticulate, except the area from brachial cell to anal margin of wing, including first apical cell; two distinct sclerotized dark vein areas (SDV): (1) a small rounded area at clavus near wing base adjacent to claval sulcus and (2) a large H-shaped area located at about 0.25 proximal of wing, between ScP&RA&M and claval sulcus, costal portion of ‘H’ smaller than anal portion. Hind wings membranous and densely coated by brochosomes. Metathoracic leg with femoral chaetotaxy with setal formula 2:0:1:0 (AD1 and PD1 + AD3?) and 2:2:2:1 (= fig. 56 of Rakitov 1998; AD1 and PD1 + AD2 and PD2 + AD3 and PD3 + AD4); tibia with anteroventral row of flattened and same size setae along entire length, posteroventral row dimorphic, with hair-like longer setae at about proximal 0.66 and with shorter flattened setae at distal 0.33; ratio of length of each individual tarsomere by total tarsus length (excluding pretarsus) equal to 0.41, 0.29 and 0.29, respectively.

Coloration. Head and thorax ground color brownish to ochre-yellow with few light brown to brown irregular areas. Crown with pair of ill-defined light brown spots over M-shaped elevation adjacent to posterior margin, larger than ocellus. Pronotal disc orange-yellow over V-shaped mesal anterior callosity; lateral and ventral surfaces of thorax similar in color to dorsal surface, legs brownish-yellow proximally, brown to dark brown distally, prothoracic tibia and tarsus dark brown to black, mesothoracic tibia slightly lighter, metathoracic tibia light brown, tarsal claws dull reddish-brown in all legs. Forewing with two SDVs, one small basal spot and large typical Hshaped marking at anterior 0.25; entire anal margin of clavus, continuing over inner margin of apical cell, brown to dark brown. Hind wings translucent white. Abdomen color lost due to maceration.

Male terminalia (based on the holotype). Pygofer ( Fig. 63 ) dorsal margin slightly concave at middle; posterior margin rounded ventrally, dorsoposterior margin with wide concavity and slightly emarginated dorsally; microsetae distributed throughout lobe. Valve, in ventral view, transverse, subrectangular; fused laterally to pygofer lobe; articulated to subgenital plate. Subgenital plate ( Fig. 64 ) subquadrangular, 1.1 times longer than wide at base in ventral view; posterior margin broadly rounded; dorsal surface with strong tooth-like process near outer margin, associated with style apex; microsetae distributed throughout ventral surface, slightly longer posteriorly. Style ( Fig. 65 ), in dorsal view, without preapical lobe; apex of apophysis truncate, directed posteriorly; ventral margin with small, preapical dentiform process and two minute apical processes. Connective ( Fig. 65 ) Y-shaped, 2.4 times longer than maximum width at base; arms joined anteriorly in dorsal view. Aedeagus ( Figs. 78–80 ) strongly sclerotized; broad basally, gradually narrowing distally into cylindrical, curved, sickle-shaped shaft; shaft apex truncated in lateral view, slightly expanded dorsally; basiventral process cylindrical up to about proximal 0.6, bulbous and with spine-like process basally, constricted before bifurcating into pair of biconical rami; rami of basiventral processes with tips surpassing shaft apex, widest at distal 0.5, distally strongly divergent in posterior view, with large concave area at divergent portion.

Female terminalia. Sternite VII ( Fig. 89 ) with maximum width about 1.8 of mesal length in ventral view; posterior margin sinuous, with three convex lobes, mesal lobe poorly projected into rounded triangular plate, not extending distally as far as lateral ones, lateral lobes with distinct longitudinal carina along entire length, strongly projected into two narrow divergent blades.

Variation of paratypes. Female and male paratypes are very similar to the holotype, though some are more densely coated by brochosomes; other minor differences are here described. Crown maximum length 0.52–0.62 of transocular distance and almost the same as interocular distance (ratio of 0.82–0.95) in dorsal view; some males and females with anterior margin with a very small concavity at insertion of the nymphal blade-like frontal process. Ratio of distances between ocellus and eye with eye to mesal line 0.17–0.25. Longitudinal posterior carina on mesonotum varying from defined to ill-defined. Forewing with the large H-shaped sclerotized dark vein area (SDV) imperfect with costal portion sometimes strongly reduced forming a somewhat T-shaped marking, or interrupted with costal and anal portions not in contact. Metathoracic leg with femoral chaetotaxy with setal formula greatly variable (2:0:0:0, 2:1:0:0, 2:0:1:0, 2:1:1:0, 2:0:2:0, 2:1:2:0, 2:0:1:1, 2:1:1:1 and 2:1:2:1). Female from Rondônia with sternite VII lateral lobes with very faint carinae. Abdomen largely yellowish-brown.

Measurements (mm, n = 4). Usually females are larger than males, but largest males are larger than smallest females. Total length (from anterior of head to tip of forewings) 18.3–20.8; crown length 2.0–2.4; interocular distance 2.5–2.7; transocular distance 3.9–4.0; distance between compound eye and mesal line 1.0–1.3; distance between ocellus and mesal line 0.8–0.9; pronotal disc maximum width 4.5–4.9; pronotal disc maximum length 3.7– 3.9; forewing length 14.4–16.6; metathoracic femur length 3.7; metathoracic tibia length 6.7–7.8.

Diagnosis. A large, dorsolaterally white and ventrally yellowish-brown Diestostemma with two pronotal humps and small dark areas on the forewing. Males and females of D. cavichiolii sp. nov. are the smallest amongst species of the D. bituberculatum complex and can be distinguished from almost all species of the group, except D. bituberculatum and D. rubriventris , by the pronotal disc virtually lacking dark areas. However, it can be distinguished from these two species by only two SDV areas on the forewing (few specimens of D. bituberculatum also have two SDV), abdomen yellowish-brown, and pronotal humps less projected ( Figs. 5–6 , 19–20 ; usually three SDV, abdomen realgar colored, and humps distinctly more projected in D. bituberculatum and D. rubriventris , Figs. 3–4 , 39–40, 45 , 48–49, 54–55 ).

Males are easily distinguished from all known males of the D. bituberculatum complex by the large spine-like process at the proximal portion of the basiventral process of aedeagus and biconical shape of the process rami in posterior view ( Figs. 78–80 ; proximal portion of basiventral process lacking process and rami slightly to strongly flattened in all other species, Figs. 72–77 , 81–86 ).

Females posterior margin of sternite VII bilobed (mesal margin very slightly projected) with lateral lobes reaching distally farther than mesal margin. These characters allow the separation of D. cavichiolii sp. nov. from all species of the complex, except D. gervasioi sp. nov. and D. rubriventris ( Fig. 89 ; sternite VII trilobed in D. albinoi sp. nov., D. bituberculatum and D. olivia sp. nov., Figs. 87–88, 91 ). The new species can be distinguished from these two species by its sternite VII lateral lobes with a distinct longitudinal carina along the entire length and tips divergent in ventral view ( Fig. 89 ; lateral lobes not carinated and tips almost parallel in D. gervasioi sp. nov. and D. rubriventris , Figs. 90, 92 ).

Distribution. Known from three localities at the Brazilian Amazonian Forest at Rondônia State and at the Cerrado Domain in the Chaco biogeographical province at Mato Grosso State, Brazil ( Fig. 93 ). Although present in the Cerrado, most likely this species inhabits riparian forests with a strong Amazonian connection.

Biological and ecological data. The single male from Rondônia was collected using a light sheet apparatus, similarly to almost all samples of Diestostemma species preserved in collections.

Etymology. Specific name based on the surname in genitive singular after the eminent leafhopper specialist Rodney Ramiro Cavichioli (Universidade Federal do Paraná), a former student of Dr. A.M. Sakakibara, in honor of his contribution to our knowledge of sharpshooters and the first researcher to identify this species as new.

Remarks. The sternite VII of the female from Rondônia shows lateral lobes less carinated than other specimens, though it can be clearly associated to this species. Diestostemma cavichiolli sp. nov. is the smallest species of the complex and the pronotal humps are less projected than in all other species, thus it somewhat deviates from the diagnostic features of the group.

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 1 – 12. Head and prothorax of species of the Diestostemma bituberculatum complex in anterior view. 1 – 2. Male holotype and female paratype of D. albinoi sp. nov. (Ecuador, Orellana Province, EPNC, USNM); 3 – 4. Male and female of D. bituberculatum (Signoret, 1855) (French Guiana, Cayenne Arrondissement, INHS, DZRJ); 5 – 6. Male holotype and female paratype of D. cavichiolii sp. nov. (Brazil, Mato Grosso State, DZUP); 7 – 8. Male holotype and female paratype of D. gervasioi sp. nov. (Ecuador, Orellana Province, EPNC, USNM); 9 – 10. Male holotype and female paratype of D. olivia sp. nov. (Ecuador, Orellana Province, EPNC, USNM); 11 – 12. Male and female of D. reticulatum (Melichar, 1924) (Peru, Cusco Department, DZRJ). Scale bars = 2 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.

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 56 – 71. Male terminalia of species of the Diestostemma bituberculatum complex, pygofer in lateral view (56, 59, 63, 66, 69), subgenital plate in ventral view (57, 60, 64, 67, 70), and style and connective in dorsal view (58, 61 – 62, 65, 68, 71). 56 – 58. Paratype of D. albinoi sp. nov. (Ecuador, Orellana Province, DZRJ); 59 – 62. D. bituberculatum (Signoret, 1855) and detail of connective variation (French Guiana, Cayenne Arrondissement, INHS); 63 – 65. Holotype of D. cavichiolii sp. nov. (Brazil, Mato Grosso State, DZUP); 66 – 68. Holotype of D. gervasioi sp. nov. (Ecuador, Orellana Province, EPNC / USNM); 69 – 71. Holotype of D. olivia sp. nov. (Ecuador, Orellana Province, EPNC / USNM). Scale bars: 56, 59, 63, 66, 69 = 1 mm; 57 – 58, 60 – 62, 64 – 65, 67 – 68, 70 – 71 = 0.5 mm.

FIGURES 72 – 80. Aedeagi of species of the Diestostemma bituberculatum complex in lateral view (72, 75, 78), basiventral processes in posteroanterior (73, 76, 79) and posteroventral (74, 77, 80) views. 72 – 74. Paratype of D. albinoi sp. nov. (Ecuador, Orellana Province, DZRJ); 75 – 77. D. bituberculatum (Signoret, 1855) (French Guiana, Cayenne Arrondissement, INHS); 78 – 80. Holotype of D. cavichiolii sp. nov. (Brazil, Mato Grosso State, DZUP). Scale bars = 0.5 mm. Abbreviations: AB = aedeagal basiventral process bifurcation; AP = aedeagal basiventral process; AR = aedeagal basiventral process ramus; AS = aedeagal shaft; ED = ejaculatory duct.

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 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 81 – 86. Aedeagi of species of the Diestostemma bituberculatum complex in lateral view (81, 84), basiventral processes in posteroanterior (82, 85) and posteroventral (83, 86) views. 81 – 83. Holotype of D. gervasioi sp. nov. (Ecuador, Orellana Province, EPNC / USNM); 84 – 86. Holotype of D. olivia sp. nov. (Ecuador, Orellana Province, EPNC / USNM). Scale bars = 0.5 mm. Abbreviations: AB = aedeagal basiventral process bifurcation; AP = aedeagal basiventral process; AR = aedeagal basiventral process ramus; AS = aedeagal shaft; ED = ejaculatory duct.