Dilobopterus nelsoni, Quintas & Felix & Lima & Mejdalani, 2017

Quintas, Victor, Felix, Márcio, Lima, Douglas Felipe Dos Santos & Mejdalani, Gabriel, 2017, Two new species of Dilobopterus Signoret, 1850 and the male of D. segmentalis (Signoret, 1853) from Southeastern Brazil, with taxonomic notes on the genus (Hemiptera: Cicadellidae: Cicadellini), Zootaxa 4281 (1), pp. 127-134 : 128-130

Dilobopterus nelsoni sp. nov.

( Figures 1–8 , 26 )

Total length 6.7 mm (male holotype), 6.6–6.8 mm (male paratypes, n = 5).

Head and thorax. Head ( Figs. 1 , 26 ) moderately produced anteriorly; median length of crown approximately 1/ 2 of interocular width and 3/10 of transocular width; antennal ledges, in lateral view, with anterior margin steeply declivous, slightly concave superiorly and slightly convex inferiorly; face with frons convex, swollen, muscle impressions inconspicuous; epistomal suture incomplete; clypeus, in lateral view, slightly swollen, its profile continuing contour of lower portion of frons. Thorax ( Figs. 1 , 26 ) with lateral pronotal margins approximately parallel; posterior margin slightly concave; dorsopleural carinae strongly declivous anteriorly. Forewings ( Figs. 2 , 26 ) mostly membranous, translucent; veins mostly distinct, except on clavus. Hind legs with meron slightly exposed; femoral setal formula 2:1:1; length of first tarsomere approximately equal to combined length of second and third tarsomeres. Other features of head and thorax as in the generic description of Young (1977: 104).

Color ( Figs. 1–2 , 26 ). Ground color of anterior dorsum (head, pronotum, and mesonotum) dark brown to black with yellow spots as follows: crown with eight (holotype) small spots, three pairs around ocelli, one pair on central portion close to posterior margin (two paratypes with additional pair on anterior margin); pronotum (holotype) with four spots, pair of smaller ones on anterior third and pair of larger ones, closer to lateral margins, on median third (two paratypes without anterior pair of spots; one paratype with five small spots near anterior margin and no posterior pair of spots; one paratype with four small spots near anterior margin plus posterior pair of spots); mesonotum (holotype) with pair of smaller spots laterobasally on scutum and pair of larger spots laterobasally on scutellum (in the paratypes, the first pair of spots can be very small or even absent). Forewings brown to dark brown, translucent, with large vitreous area on basal half occupying much of discal and brachial cells on corium and outer area of clavus but divided diagonally by dark brown claval sulcus. Face with frons dark brown to black medially and yellow laterally; centrolateral portions of frons with alternating dark brown to black and yellow narrow transverse stripes; clypeus, much of lorum, maxillary plate, and posterior area of gena dark brown to black, anterior area of gena yellow; labrum and labium mostly yellow. Thorax laterally mostly yellow, ventrally with more extensive dark brown to black areas; legs mostly yellow. Abdomen, in ventral view, yellow, with dark brown to black marks on basal portions and central area of sternites; subgenital plates, in ventral view, brownish-yellow, apex dark brown; pygofer mostly red.

Male genitalia. Pygofer ( Fig. 3 ), in lateral view, strongly produced posteriorly; posterior margin convex; without processes; with numerous dispersed macrosetae absent only on basal fourth. Subgenital plates ( Fig. 4 ), in ventral view, triangular, not extending as far posteriorly as pygofer apex; separate throughout their length; with uniseriate macrosetae along outer margin, microsetae also present. Connective ( Fig. 5 ), in dorsal view, Y-shaped; with median keel; not extending as far posteriorly as style apex. Style ( Fig. 5 ), in dorsal view, with apophysis elongate; without conspicuous preapical lobe; apex obliquely truncate, foot-shaped. Aedeagus ( Fig. 6 ) symmetrical; shaft, in lateral view, with large dorsal lobe; without processes; gonoduct distinct; gonopore located apically. Paraphyses ( Figs. 7–8 ), in dorsal view, with stalk elongate and expanded apically; expanded portion of stalk bearing pair of processes directed anteriorly; rami conspicuously asymmetrical; left ramus with larger spine basally and smaller one medially; right ramus bifurcated basally into ventral and dorsal arms, both armed with inner spine.

Female unknown.

Intraspecific variation. The number and position of the yellow spots of the anterior dorsum vary intraspecifically as detailed above in the description.

Known distribution. Atlantic Rainforest, Southeastern Brazil, Rio de Janeiro State.

Type material. Male holotype: “BR/RJ [Rio de Janeiro State] - Angra dos Reis, \ Usina nuclear \ 26/II/2002 \ N. Ferreira-Jr. col.” ( MNRJ) . Paratypes: five males, four with the same data as the holotype ( MNRJ, DZRJ) and one “BR/RJ - Angra dos Reis, \ Perequê 24-25/V/2002 \ N. Ferreira-Jr. col.” ( MNRJ) .

Etymology. The new species is described in honor of our colleague and friend Prof. Dr. Nelson Ferreira Junior (Departamento de Zoologia, Instituto de Biologia, Universidade Federal do Rio de Janeiro) in recognition of his contribution to the study of Brazilian aquatic beetles. He was the collector of the type series.

Taxonomic notes. Among the known Dilobopterus species, D. nelsoni sp. nov. is most similar to D. demissus (Fabricius, 1803) , D. dispar (Germar, 1821) , and D. disparulus Young, 1977 . In these three species, the ground color of the anterior dorsum is dark brown or black with brown or yellow marks (see Wilson et al. 2009) and the rami of the paraphyses are asymmetrical. Dilobopterus nelsoni sp. nov. can be distinguished from these three species, as well as from the remaining ones of the genus, by the following combination of features: (1) crown ( Figs.

1, 26 ) with eight small yellow spots, being three pairs around the ocelli and one pair on the central portion close to the posterior margin (an additional pair can be present on the apical portion); (2) stalk of the paraphyses ( Fig. 8 ) elongate, expanded apically and with a pair of processes directed anteriorly; (3) rami of the paraphyses ( Figs. 7–8 ) strongly asymmetrical and armed with spines (left ramus with a larger spine basally and a smaller one medially; right ramus bifurcated basally into ventral and dorsal arms, both armed with an inner spine); and (4) dorsal lobe of the aedeagus ( Fig. 6 ) large, without emarginations or processes.

Figures

FIGURES 1 – 8. Dilobopterus nelsoni sp. nov. 1, head, pronotum, and mesonotum, dorsal view (male paratype). 2, forewing. 3 – 8, male genitalia. 3, pygofer, lateral view. 4, valve and subgenital plate, ventral view. 5, connective and style, dorsal view. 6, ejaculatory reservoir, aedeagus, and basal segment of anal tube, lateral view. 7, paraphyses, laterodorsal view. 8, paraphyses, dorsal view. Scale bars: 1 = 1 mm, 2 = 2 mm, 3 – 8 = 0.5 mm.

FIGURES 26 – 29. Body in dorsal view (antennae and legs not depicted). 26, Dilobopterus nelsoni sp. nov., male holotype (total length 6.7 mm). 27, D. sakakibara sp. nov., male holotype (t. l. 6.9 mm). 28, D. segmentalis (Signoret, 1853), male (t. l. 9.0 mm). 29, D. trinotatus (Signoret, 1853), female (t. l. 9.0 mm). The last three species belong to the trinotatus group (see text for details).