Geelus viertanddraad, Stiller, 2020

Stiller, Michael, 2020, A new leafhopper genus Geelus and 12 new species (Hemiptera, Cicadellidae Deltocephalinae) from Southern Africa, Zootaxa 4786 (3), pp. 301-344 : 335-337

Geelus viertanddraad sp.n.

( Figs 18 A–D, 19A–L)

Diagnosis. Aedeagal shaft tubular, in lateral and dorsal view straight, subbasally with paired, ventral teeth, subapically with paired, dorsal teeth; dorsal apodeme membranous, produced anteriad; preatrium semispherical. Pygofer lobe rectangular, apices rounded, dorso-apical process straight, oriented ventromediad. Female sternite 7 with wide, shallow, uniformly curvate notch.

Etymology. Afrikaans nouns in apposition, vier, four, tand, tooth, and draad, wire, for the four teeth on the aedeagal shaft. Gender masculine.

Color. Male and female. The short series of specimens is yellow to pale yellow. ( Figs 18A, B ). Crown and pronotum yellow ( Fig. 18C ).

Male. Measurements. n=5. Length from apex of crown to apex of tegmina 5.11–5.31 mm. Crown median length 0.46–0.50 mm. Crown length next to eye 0.33–0.38 mm. Pronotum length 0.55–0.59 mm. Head width across eyes 1.39–1.44 mm. Pronotum width 1.31–1.35 mm. Ocellus diameter 56.0 μm; interocular distance 68.7–82.5 µm. Apical angle of crown 112.6°±3.0°.

Pygofer lobe. Process orientation, ventromediad; process acuminate, with subapical tooth on ventral margin; process origin, medially near posterodorsal margin of pygofer lobe; process straight; pygofer lobe widely merged with pygofer, dorsally indicated by acute notch; lobe rectangular, posterior dorsal and ventral apices rounded; anterior apodeme long, position dorsolateral ( Figs 19E, 19G ). Subgenital plate and pygofer lobe apices equidistant ( Fig. 19E ).

Anal tube. Ventrobasal margin produced into sclerotized, ventrad, rounded lobe ( Fig. 19E ), without membranous recess. In dorsal view with medial margins constricted as in Fig. 19G .

Subgenital plate. Number of macrosetae, more than 40 long and short macrosetae, up to 5 irregular rows along lateral margin; medioposterior angle acute, narrowly rounded, distal lateral margin straight, basal lateral margin curvate; length: width, 1.1–1.5; position of style relative to subgenital plate and valve, extending half-way into subgenital plate ( Fig. 19F ).

Valve. Shape lenticular ( Fig. 19F ).

Style. Apophysis without large ventral tooth, but fine serration laterally; apophysis digitate, sublinear, width half as wide as width across preapical lobe; preapical lobe obtuse; ratio of length to width of apophysis 2.3–2.7 ( Fig. 19D ).

Connective. Stem length relative to arm length, one third length of arms; stem width relative to width across arms, about half as wide ( Fig. 19H ).

Aedeagus. Shaft thick, tubular; apex of shaft rounded, desclerotized, shaft subapically with dorsolateral paired teeth, subbasally with ventral paired teeth, both pairs similar, curvate, blunt; shaft sclerotized, straight in lateral and dorsal or ventral views; dorsal apodeme desclerotized, in lateral view, directed anteriad, in dorsal view forked, elongate, slightly asymmetric; preatrium semispherical ( Figs 19 A–C).

Female. Measurements. n=3. Length from apex of crown to apex of tegmina 5.18–5.40 mm. Crown median length 0.50 mm. Crown length next to eye 0.37 mm. Pronotum length 0.56 mm. Head width across eyes 1.41–1.47 mm. Pronotum width 1.34–1.36 mm. Ocellus diameter 44.7–57.9 μm; interocular distance 72.7–85.9 µm. Apical angle of crown 110.9°±1.2°.

Sternite 7. Posterior margin with wide, shallow, uniformly rounded notch, as wide as width of sternite 7. Sternite 8 desclerotized ( Figs 18D , 19L ).

Valvifer 1. In lateral view, irregularly rectangular, anterior angle acute, dorsal margins of both valvifers round- ed, and ventral margins more or less straight ( Figs 19I, J ), anterior margin fused to valvula 1; in dorsal view, merged broadly ( Fig. 19K ), forming a furrow-like structure with ventral margin.

Material examined. Holotype male. Namibia , CCDL27841 , Kamanyab, (-19.629, 14.841), Jan[uary]–Mar[ch] 1925, Mus[useum] Exped[ition] ( SANC) . Paratypes. 4♂, 3♀. Namibia , 4♂, 3♀, ibid. holotype. ( SANC) .

Remarks. Four males and one female were dissected, without signs of parasites. Specimens were remounted onto card points from minutens on card rectangles. Present spelling of the locality is Kamanjab, Kunene region in north western Namibia . The color and rounding of the crown corresponded with the other species of Geelus . The aedeagus of this species is thick, as in G. haakdraad , G. kinkeldraad , G. lemdraad , G. nektanddraad and G. stompdraad , and with some correspondence to G. haakdraad . Distinguishing features of the aedeagus between G. viertanddraad and G. haakdraad are the former with straight shaft, subapical and subbasal paired teeth; the latter with sublinear shaft, subapical lateral paired teeth and dorsal, disk-like complex structure respectively. Unique in this species is the ventral basal lobe of the anal tube, and additionally the aedeagus with semicircular preatrium and asymmetric, desclerotized, anteriad dorsal apodeme. The subgenital plate is triangular, with distal medial and lateral margins straight, to a greater degree than in any other species of Geelus . In this regard there is some similarity to G. dundraad or G. driehoekdraad , but both have the entire lateral margin curvate. The pygofer lobe is rectangular, as in G. haakdraad and G. lemdraad .

Figures

FIGURE 18. Geelus viertanddraad gen.n. & sp.n., male and female, habitus views. A. Male, dorsally; B. Female, dorsally; C. Head, dorsally; D. Sternite 7, ventrally.

FIGURE 19. Geelus viertanddraad gen.n. & sp.n., male and female genitalia, line drawings. A. Aedeagus, ventrally; B. Aedeagus, laterally; C. Aedeagus, dorsally; D. Style; E. Genital capsule, laterally; F. Subgenital plate; G. Genital capsule, dorsally; H. Connective; I. Valvifer 1, laterally; J. Valvifer 1, laterally; K. Valvifer 1, dorsally; L. Sternite 7.