Discolopeus triacaenus, Stiller, 2019

Stiller, Michael, 2019, A new leafhopper genus Discolopeus and nine new species (Hemiptera, Cicadellidae, Deltocephalinae) associated with shrubs, trees and poisonous plants in South Africa, Zootaxa 4559 (2), pp. 201-244 : 226-227

Discolopeus triacaenus sp.n.

Fig. 14 a–h 15g–i, 19c.

Diagnosis. Crown short; two pairs of small wedge-shaped dark brown markings apically and subapically. Subgenital plate obovate; ratio of length to width 0.87–1.28. Aedeagal shaft apex anterodorsally with single tooth, subapex laterally with short paired tooth; uniformly curved posterodorsally, tubular; dorsal apodeme in dorsal view transverse bar-shape; aedeagal process long, subparallel, straight, acuminate, distal third acanthoid. Style apophysis acutely triangular, dorsomedially with narrow, right-angled digitate process. Connective with midsection concave, arms short. Pygofer lobe apex with sclerotized, acuminate, ventroposteriad process. Tergite X rectangular; tubular in dorsal view, apex ventrally with short, sclerotized, digitate, posteriad process.

Etymology. Named for the three teeth on the apex and subapex of the aedeagal shaft, with two nouns in apposition, Greek, three, trias, and tooth, akaina.

Male. External morphology. Specimens stramineous, with small dark brown to black marking submarginally on apex of crown ( Figs 15g, 15i ) or large marks with transvers line across disc ( Fig. 15h ). Pronotum with two pairs of circular brown marks near posterior margin of eye. Tegmina with brown marks in some cells and most veins embrowned ( Figs 15 g–i).

Male. Measurements. Overall length 4.80–4.86 mm; crown length 0.41–0.47 mm; crown length next to eye 0.37–0.38 mm; pronotum length 0.52–0.55 mm; head width 1.3 8– 1.44 mm; pronotum width 1.32–1.40 mm; ocellus diameter 42.0 µm; interocellar distance 56.0 µm.

Male. Genitalia. Genital capsule short in lateral view, large lobulate anterior apodeme in Willowmore and Beaufort West specimens (as in Figs 11a, 11b ), absent in Oudtshoorn specimen ( Fig. 14a ). Tergite X long, tubular, with sclerotized process on ventroposterior margin ( Fig. 14a ). Subgenital plate extending beyond posterior margin of pygofer lobe ( Fig. 14b ). Pygofer lobe with wide, triangular base, apex with sclerotized, acuminate, ventroposteriad process; macrosetae dorsomedially, up to 15 long macrosetae, about 8 shorter macrosetae ( Fig. 14b ). Subgenital plate with medial margin straight, adjacent margins subparallel; lateral margin at base concave; distally curvate, posterior margin curvate; macrosetae grouped near apex, up to 20 macrosetae, fine setae apically and laterally ( Fig. 14c ). Subgenital plate with ratio of length to greatest width 0.87–1.28 (n=3). Aedeagus with shaft tubular, curvate, apex with single, anterodorsal tooth and subapically with paired lateral tooth ( Figs 14e, 14f ); ventrodistal half of shaft with membranous ridge surrounding gonopore ( Fig. 14e ); dorsal apodeme in lateral view short, in dorsal view transverse with short arms ( Fig. 14f ), atrium elongated, articulated with connective at midsection, aedeagal paraphysis elongate, longer than shaft, tubular, apex acuminate or with small barb, distal third acanthoid ( Figs 14d, 14e ). Style with apophysis weakly sclerotized, straight, broadly acuminate, directed posteriad, dorsally at mid-section with digitate, right-angled process, process as long as width across mid-section; preapical lobe rounded, preapical angle acute; anterior medial arm short, anterior lateral arm elongate ( Figs 14g, 14h ). Connective with mid-section concave, long, arms short, right-angled to mid-section ( Fig. 14f ).

Female. Unknown.

Material examined. Holotype male. Eastern Cape Province. Willowmore , (-33.2801 23.4861), 16.i.1984 J.G. Theron . Paratypes 2♂. 1♂, Rust en Vrede (waterfall) Oudtshoorn (-33.3943 22.3575), Mus (eum) Expedition, x.1951 ; 1♂, Beaufort West (-32.3517 22.5908), 24.i.1982 J.G. Theron .

Remarks. Of the specimens examined, from Beaufort West ( Fig. 15i ), Rust en Vrede near Oudtshoorn ( Fig. 15g ) and Willowmore ( Fig. 15h ), all were dissected previously, so the original position of the aedeagus within the genital capsule is unknown. Apices of the aedeagal paraphysis are broken off in the Beaufort West specimen and the Rust en Vrede, Oudtshoorn specimen has the subgenital plate dismembered. The colour pattern of the crown of the holotype ( Fig. 15g ) and Beaufort West specimen ( Fig. 15i ) is lighter and in the Oudtshoorn specimen it is darker ( Fig. 15h ). Styles with a medial digitate process are also found in D. tetracaenus . Discolopeus thigmacaenus has a similar style, but without the median digitate process. All other species of Discolopeus have digitate, compressed or depressed style apophyses, with serrate ventral margins and sometimes a single larger apical or ventral tooth. The point distribution map of D. triacaenus is in Fig. 19c .

Figures

FIGURE 11a–h. Discolopeus thigmacaenus n.gen. & sp., male and female genitalia, line drawing. a. Genital capsule, dorsally; b. Genital capsule, laterally; c. Subgenital plate, ventrally; d, e. Aedeagus, laterally and dorsally respectively; f. Style, dorsally; g. Connective; h. Sternite VII.

FIGURE 14a–h. Discolopeus tetracaenus n.gen. & sp., male and female genitalia, line drawing. a. Genital capsule, dorsally; b. Genital capsule, laterally; c. Subgenital plate, ventrally; d, e, f. Aedeagus, ventrally, laterally and dorsally respectively; g. Style, dorsally; h. Style apophysis, laterally.

FIGURE 15a–i. Discolopeus gen.n. species, habitus, D. triacaenus sp.n. a. Holotype, male; b. Paratype, male, Ladismith; c, d, e. Nietgenaamd, female; dorsally, laterally and face, respectively; f. Ladismith, female; D. tetracaenus sp.n.; g. Beaufort West, male; h. Rust en Vrede, Oudtshoorn, male; i. Holotype, male, Willowmore.

FIGURE 19a–c. Distribution maps of leafhopper species of Discolopeus gen.n. and associated plants. a. Hyaenanche globosa near Vanrhynsdorp and one record near Citrusdal (red squares); b. Potential natural distribution of D. copeus sp.n. in the southwestern parts of South Africa, Western Cape Province; c. Point distributions of D. colopeus sp.n., D. lissus sp.n., D. tetracaenus sp.n., D. thigmacaenus sp.n., D. triacaenus sp.n. and D. viraktamathi sp.n. in Western, Northern and Eastern Cape Provinces.