Tryella, Moulds, 2003

Moulds, M. S., 2003, An Appraisal of the Cicadas of the Genus Abricta Stål and Allied Genera (Hemiptera: Auchenorrhyncha: Cicadidae), Records of the Australian Museum 55, pp. 245-304 : 271-272

Genus Tryella n.gen.

Type species: Tryella ochra n.sp.

Included species: adela n.sp., burnsi n.sp., castanea (Distant) , crassa n.sp., graminea n.sp., infuscata n.sp., kauma n.sp., lachlani n.sp., noctua (Distant) , occidens n.sp., ochra n.sp., rubra (Goding & Froggatt) , stalkeri (Distant) , willsi (Distant) .

Etymology. Derived from the Greek tryelis meaning ladle or stirrer and pertaining to the prominent ladle-like or scoop-like uncal lobes of this genus.

Diagnosis. Postclypeus slightly to moderately produced. Rostrum almost reaching or slightly passing hind coxae. Ocelli amber to ruby red. Width of head including eyes as wide as or slightly narrower or wider than anterior part of pronotum and as wide as or narrower than mesonotum; width of abdomen equal to that of thorax. Pronotal collar narrow with lateral angles ampliate and rounded; rudimentary and essentially confluent with adjoining sclerites anterior of lateral angles. Wings hyaline or with very weak translucent tint. Fore wing with or without infuscation; costal margin ampliate to node, the maximum dilation greater than width of costal vein; basal cell usually with translucent pigmentation, hyaline in some species. Hind wing plaga broad along much of vein 3A plus inner margin of anal lobe, narrow along vein 2A usually to its distal end; plaga usually edged by black infuscation partly expanded along wing margin at distal end of 2A. Tymbals ( Figs. 22– 29) with 9–11 long ribs evenly spaced but slightly converging dorsally; basal plate small. Male opercula almost tear-drop in shape, weakly angled inwards before midpoint; nearly flat; meeting or almost meeting and extending distally to or just beyond limits of tympanal cavities. Body and basal wing veins bearing silver pubescence, varying in degree between species but most abundant on newly emerged individuals.

Male genitalia ( Figs. 48–49, 67–74, 79–86, 92–101) with pygofer dorsal beak large, long and pointed; upper pygofer lobes strongly developed in most species but in some short and robust; basal pygofer lobes usually divided into a primary outer and secondary inner lobe (undivided in occidens ), the outer lobe in lateral view either long and finger-like or substantially webbed to inner basal lobe. Uncal lobes widely separated; in ventral view somewhat scoop-like, the distal end of each upturned and cupped; in lateral view with a wing-like lateral process near base, sometimes short, sometimes long. Aedeagus in lateral view straight or gently curved for most of its length, basal plate a fused pair of nearly circular discs; conjunctival claws directed laterally or ventrally, robust, claw-like; some species with a flabellum and/or palearis.

Female abdominal segment 9 long, nearly conical; ovipositor ( Figs. 9–14) long, in lateral view with modest dorsal and ventral slopes, wedge-shaped; ovipositor sheath reaching to or a little beyond apex of dorsal beak.

Distinguishing features. The scoop-like uncal lobes and wing-like lateral processes of the uncus are unique to Tryella species. Tryella species also differ from allied genera except Aleeta by having the fore wing costa strongly ampliate to node, the maximum dilation clearly wider than costal vein. The conjunctival claws at distal end of male theca are far more developed in Tryella than in other genera.

Remarks. The separation of Tryella from Aleeta (its sister group in Australia) is strongly supported both by electrophoretic data (Serkowski & Moulds, unpub. data) and the cladistic analyses. Electrophoretic data show a long genetic distance between the six Tryella species examined and Aleeta curvicosta , while cladistic analyses of morphological data show strong character support for this generic separation ( Figs. 15–17). For details see Rationale for New Taxa, pp. 254–255.

Distribution. Mainly tropical and subtropical Australia, both coastal and inland, but also central Australia, temperate eastern Australia and southwestern Papua New Guinea.

Habitat. The majority of species inhabit trees and shrubs, especially Eucalyptus and other Myrtaceae . One species, T. graminea , is confined to grass. Adults inhabiting trees and shrubs perch along the trunks and branches, but are found most often on those with a diameter less than 50 mm.

Biology. In monsoonal and arid regions adults mostly emerge after heavy summer rains. Eggs are probably laid in live plant tissue but this requires confirmation.

Adults of all species tend to group together in local aggregations, those of some species even clustering on just one or several adjoining trees or shrubs. They are active both during the day and at dusk and all species, except perhaps graminea , are readily attracted to light. In fact the large majority of specimens in collections has been taken in this way.

Males call both during the day and at dusk. Calling males tend to aggregate and singing usually occurs in chorus.