Tryella lachlani, 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 : 289-290

Tryella lachlani n.sp.

Figs. 12, 56a,b, 73, 74, 90

Species “G” Ewart, 1993: 139–140, fig. 14.

Abricta sp. –Zborowski & Storey, 1995: 87 (figured).

Types. QUEENSLAND— Holotype 3, K179837, York Downs , 50 km E of Weipa, 28.xii.1983, MBM , in AM. Paratypes as follows: 233, K179838 and K179839, 2♀♀, K179840 and K179841, same data as holotype; 233, K46340 , K179986, Moa , Banks I., Torres St., 10.i.1920, W. McLennan; all in AM . 13, Hammond Island , 10.i.1964, B.M. 1964-179, M. Nikitin, in BM . 433 (1 male genitalic preparation no. AB19), 4♀♀, Hammond Island , Torres Strait, 14.i.1987, R . B. Lachlan; 13, Hammond Island , Torres Strait, 14.xii.1974, R . B. Lachlan; 5733 (3 male genitalic preparations Nos AB 18, AB80, AB87), 38♀♀, same data as holotype; 433, 2♀♀, waterhole nr Wenlock Riv. x-ing, Portland Roads rd, 13°06'S 142°56'E, 120 m, 31.xii.1994, GAD ; 1♀, near Mt Croll N of Coen, 8.i.1988, MBM ; all in MSM. 233, 1♀, same data as holotype; all in QM . 1♀, Moa I., Torres Strait , (no date), J.W. Schomberg, in SAM . PAPUA NEW GUINEA —1 3, Oriomo Agr. Sta , W Distr., i–iv.1960, G. Rio, in DPIB .

Etymology. Named after Robert Lachlan who collected the first examples of this species seen by me, as well as many other rare and valuable cicadas.

Description

Male ( Figs. 56a, 73, 74). Head. Black with ferruginous postclypeus that sometimes has its midline blackened; anteclypeus ferruginous to black. Rostrum brown and black, usually black dorsally and at apex; passing bases but not apices of hind coxae. Antennae black or brown. Head usually with some fine silver pubescence, primarily confined to lorum below. Thorax. Pronotum ochraceous with a broad black middorsal fascia that spreads laterally both against anterior margin to back of eyes and against posterior margin to merge with black pronotal collar. Mesonotum ferruginous except for black around cruciform elevation, this black pale on teneral or partly teneral individuals. Thorax above usually without obvious silver pubescence. Thorax below black or nearly so and bearing fine silver pubescence. Wings. Hyaline. Fore wings usually without noticeable infuscations but often with an extremely weak infuscation at distal end of apical cell 1 and a few individuals also very weakly infuscated at base of apical cell 2 and sometimes 3; venation black or sometimes brown, costa ochraceous; basal cell weakly tinted translucent amber; basal membrane orange; costa and veins on basal third or so sometimes bearing a little silver pubescence not visible to naked eye. Hind wings with a smoky black infuscation at distal end of vein 2A which, in most specimens, fills the distal end of anal lobe, the proximal end sharply pointed; remainder of anal lobe suffused translucent amber hiding cream plaga; venation tending pale brown basally becoming dark towards apex. Legs. Ferruginous often with black in region of fore leg femoral spines. Opercula. Black or nearly so; usually covered by silver pubescence not always obvious to naked eye; clearly separated exposing apex of sternite I and barely concealing tympanal cavities. Abdomen. Tergites black with much of dorsal and subdorsal area ochraceous; tergite 2 substantially black; tergite 3 black with ochraceous dorsal band along posterior margin; tergites 4–7 dominantly ochraceous with black increasingly reduced to sublateral region; tergite 8 black on anterior half or a little less, otherwise ferruginous. Sternite 2 black; sternites 3–8 ferruginous, 3–6 often with pale cream posterior margins to varying extent. Abdomen above and below without noticeable pubescence. Tymbals. Usually 11 long tymbal ribs, otherwise as for generic description. Genitalia ( Figs. 73, 74). Pygofer black and ochraceous, usually black dorsally and partly or entirely so laterally; upper pygofer lobe in lateral view very broad at base, gradually tapering to a sharp or rounded point at apex, and usually very gently curved upwards, in ventral view nearly straight and tilted slightly inwards; basal lobe in lateral view like a very long thin finger, gently curved, nearly equal in length to upper pygofer lobe, not fused with inner secondary lobe by broad webbing. Uncal lobes scoop-like and gently upturned at their distal ends; lateral process of uncus in lateral view small and rounded. Conjunctival claws simple, sharply pointed, directed ventrally. Flabellum a very small mid-ventral rounded lobe. Palearis adjoining flabellum and continuing along much of length of theca, small and gradually tapering to zero at proximal end.

Female ( Figs. 12, 56b). Colour and markings similar to male except for abdomen above. Dorsal and subdorsal areas dominantly ochraceous but usually less brilliant than that of male, otherwise black; a black middorsal blotch usually present at base; tergite 8 always with a distinct black band following anterior margin. Abdominal segment 9 dull ochraceous to brown with dorsal area and dorsal beak black. Ovipositor sheath black or dark brown; extending clearly beyond dorsal beak.

Measurements. n = 1033, 10♀♀ (includes smallest and largest of available specimens). Length of body: male 15.1– 19.2 (17.0); female 17.1–20.0 (18.4). Length of fore wing: male 22.1–25.3 (23.1); female 22.0–27.1 (24.1). Width of head: male 5.7–7.1 (6.3); female 6.4–7.0 (6.8). Width of pronotum: male 5.7–7.3 (6.4); female 6.2–7.2 (6.9).

Distinguishing features. It is unlikely that the distinctive male of this species, with its bright ochraceous pronotum and abdominal tergites, will be confused with that of any other Tryella species.

Females are less distinctive but nevertheless are readily identifiable by their ochraceous pronotum and abdomen, lack of (or rudimentary) fore wing infuscations and their black or blackish cruciform elevations. Confusion is most likely to occur between atypical females of lachlani and atypical females of burnsi ; the black cruciform elevation of lachlani immediately distinguishes it from burnsi which always has the cruciform elevation light brown. The Key to species should resolve doubtful cases.

Distribution ( Fig. 90). South-west Papua New Guinea, Torres Strait islands and northern Cape York Peninsula of Queensland. The specimen from Oriomo on mainland Papua New Guinea just north of Daru Island, represents the only record of any Tryella or allied species from Papua New Guinea. From Queensland there are records from just five localities, Moa Island (= Banks Is.), Hammond Island, near Heathlands Station ( Ewart, 1993), York Downs (50 km east of Weipa) and near Mt Croll (near Coen). This species is sometimes locally common. Adults have been taken in December and January but they may also occur later in the season.

Habitat. Open Melaleuca woodland where adults favour the outer branches of these trees. There are no confirmed reports of adults inhabiting other tree species.

Song. Adults sing both during the day and at dusk. Ewart (1993) describes the song of this species (his Species G) as “a continuous, rapidly pulsating, high pitched humming, quite soft, and not easily located”. A frequency range from 1–10kHz was noted by Ewart and he provides an oscillogram and frequency graph of the call.