Acuthana, Domahovski & Cavichioli, 2018

Domahovski, Alexandre C. & Cavichioli, Rodney R., 2018, Two new remarkable genera and two new species of Gyponini (Hemiptera: Cicadellidae: Iassinae) from Brazil, European Journal of Taxonomy 476, pp. 1-17 : 4-7

Genus Acuthana gen. nov.

urn:lsid:zoobank.org:act:5B8D7B54-084D-4352-897C-F303E8DE6D32

Figs 2 –22, 44–45

Type species

Acuthana transgressa gen. et sp. nov.

Diagnosis

Head ( Fig. 2 ), with median length of crown slightly less than half interocular width; head surface dorsally with transverse parallel striae; ocelli closer to eyes than to median line and equidistant between anterior and posterior margins of crown; laterally ( Fig. 4 ), with crown-face transition defined with three carinae. Forewing ( Fig. 5 ) anterior half with venation indistinct, heavily punctuated; posterior half distinctly tapered toward apex, venation reticulated. Male with sternite VIII ( Fig. 6 ) triangular ventrally, strongly produced and fully hiding subgenital plates. Aedeagus ( Figs 13–14 ) with atrial processes; dorsal apodeme strongly developed laterodorsally.

Etymology

The generic name Acuthana , comes from the Latin word ‘ acutus ’ and means ‘acute’. It refers to the forewing with apical portion distinctly acute. The suffix ‘ -ana ’ is common in names of other genera of Gyponini .

Description

MEASUREMENTS. Body length: male 8.7 mm; female 9.0 mm.

HEAD ( Figs 2–4 ). Dorsal view: not produced anteriorly, median length of crown slightly less than half interocular width; crown with anterior margin broadly rounded; surface slightly convex, with transverse parallel striae; transocular width of head nine-tenths humeral width of pronotum; ocelli closer to eyes than to median line and equidistant between anterior and posterior margins of crown; frontal view: face as wide as high; clypeus ca 1.6 times longer than wide, lateral margins parallel, apex straight; maxillary plates produced ventrally as far as clypeus apex; frons as long as wide, flat, not excavated below anterior margin of crown; frontogenal suture not surpassing antennal ledges and distance from eye internal margins equal to maximum clypeus width; antennal ledge carinate and transversal; lateral view: crown-face transition defined, thick, with three clearly defined carinae.

PRONOTUM ( Fig. 2 ). Transverse striae on disc and posterior third dorsally; lateral margins shorter than eye length, convergent anterad; posterior margin slightly excavated; laterally ( Fig. 4 ) slightly declivous; head and pronotum in continuous slope.

MESONOTUM ( Fig. 2 ). Wider than long.

FOREWING ( Fig. 5 ). Anterior half with venation indistinct, heavily punctuated; posterior half distinctly tapered toward apex, venation reticulated; appendix moderately developed.

LEGS. Profemur four times longer than high; AV row formed by five–six setae and PV row absent; protibia circular-shaped in cross section; AV row formed by short setae in basal half and four–five thick, long setae in distal half; PD row formed by four long setae with some intercalary short setae; PV row developed, with four long setae; metafemur with setal formula 2:2:1; metatibia AD row with intercalary setae between macrosetae; PV row with setae of apical half long and heterogeneous in length and thickness, with long, thick setae followed by four slightly shorter and thinner setae; first tarsomere with outer row of setae absent and inner row formed by approximately nine very short setae, apex with four platellae; second tarsomere apex with two apical platellae.

MALE TERMINALIA. Sternite VIII ( Fig. 6 ) triangular, strongly produced and fully hiding subgenital plates. Pygofer ( Fig. 8 ) simple, without processes. In dorsal view, style ( Fig. 10 ) very elongated; outer lobe conspicuous. Aedeagus ( Figs 13–14 ) with atrial processes; dorsal apodeme strongly developed laterodorsally.

FEMALE TERMINALIA. Valvulae ( Figs 15 –16) surpassing pygofer apex. Second valvula (Fig. 19) curved ventrally, very elongated, more than six times longer than maximum height; apical portion (Fig. 20) with irregular teeth on dorsal margin and some small teeth on ventral margin near apex. Gonoplac (Figs 21–22) with short macrosetae near apex.

Distribution

Brazil (Mato Grosso).

Remarks

The head of Acuthana gen. nov. is similar to those of Ponana Ball, 1920 , Costanana DeLong & Freytag, 1972 , Regalana DeLong & Freytag, 1975 and Nullana DeLong, 1976 , which all have the crown surface with transverse parallel striae and the crown-face transition clearly defined, not rounded as in Polana DeLong, 1942 , and with transverse carinae or striae. The new genus is probably more related to Costanana by the shape of the male sternite VIII strongly produced and fully hiding the subgenital plates as in some species (e.g., Costanana cella DeLong & Freytag, 1972 and Costanana flavina DeLong & Freytag, 1972 ) and the shape of the subgenital plate tapered apically with apex acute, which is common in several species of this genus. However, species of Costanana are characterized by the forewings with the basal half of costal margin yellow, aedeagus without atrial processes and aedeagal shaft commonly with apical processes.

The characteristics of the forewing of Acuthana gen. nov. are very unusual. The basal half with many punctuations resembles the forewing of Dragonana Ball & Reeves, 1927 whereas the presence of reticulations on the apical half similar to Gyponana Ball, 1920 and Chloronana DeLong & Freytag, 1964 . Moreover, the very tapered wing apex is not characteristic of the genera cited. The shape of the female second valvula in Acuthana gen. nov. is very elongated like in species of Costanana . However, most genera of Gyponini , including Costanana , have the second valvula curved dorsally ( Fig. 40 ) or approximately straight, but the new genus differs by the second valvula curved ventrally, which is a highly unusual characteristic in Gyponini .

Figures

Figs 15─22. Acuthana transgressa gen. et sp. nov., paratype, ♀ (DZUP 215370), terminalia. 15. Sternite VII and pygofer, ventral view. 16. Pygofer and valvulae, lateral view. 17. First valvifer and first valvula, lateral view. 18. Apex of first valvula, lateral view. 19. Second valvula, lateral view. 20. Apex of second valvula, lateral view. 21. Second valvifer and gonoplac, lateral view. 22. Apex of gonoplac. Scale bars: 15–16 = 1.0 mm; 17, 19, 21 = 0.5 mm; 18, 20, 22 = not to scale.

Figs 2–14. Acuthana transgressa gen. et sp. nov., holotype, ♂ (DZUP 215369). 2. Head and thorax, dorsal view. 3. Head, frontal view. 4. Head and thorax, lateral view. 5. Forewing. 6–14. Male terminalia. 6. Sternite VIII, ventral view. 7. Valve, anterior view. 8. Pygofer, valve and subgenital plate, lateral view. 9. Subgenital plate, ventral view. 10. Style and connective, dorsal view. 11. Connective, lateral view. 12. Style, lateral view. 13. Aedeagus, lateral view. 14. Aedeagus, posterior view. Scale bars: 2–4 = 1.0 mm; 5 = 2.0 mm; 6–10, 12 = 0.5 mm; 11, 13–14 = 0.25 mm.

Figs 36–43. Rectapona nigrifascia gen. et sp. nov., paratype, ♀ (DZUP 215372), terminalia. 36. Sternite VII and pygofer, ventral view. 37. Pygofer and valvulae, lateral view. 38. First valvifer and first valvula, lateral view. 39. Apex of first valvula, lateral view. 40. Second valvula, lateral view. 41. Apex of second valvula, lateral view. 42. Second valvifer and gonoplac, lateral view. 43. Apex of gonoplac. Scale bars: 36–37 = 1.0 mm; 38, 40, 42 = 0.5 mm; 39, 41, 43 = not to scale.