Illyria viridis Moulds & Marshall 2022, sp. n.
Creators: name: Moulds, Max
name: Marshall, David C.
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Cicadidae
Illyria
Illyria viridis

description: Illyria viridis sp. n.
urn:lsid:zoobank.org:act: C2761892-97A3-4C9F-AF66-B10AB3A977C6
(Figs 1, 15, 21–23)
Common name. Yidiyidi, the name originating from the Wuggubun people who know this cicada well.
Etymology. Named from the Latin adjective viridis meaning green and pertaining to the green colour of this species.
Types. Holotype male, 40 km E of Durack R. x-ing, Gibb R. road, Western Australia, 29.xii.1991, M.S. & B.J. Moulds (WAME 113416) (WAM). Paratypes as follows: WESTERN AUSTRALIA: 2 males, 40 km W of Kununurra, 6.i.1986, M.S. & B.J. Moulds (AMS). 4 males, 3 females, Durack, Great Northern Highway, 16.005°S 128.418°E, 21.i. 2020, S. Ong; 1 male, near Molly Springs, Victoria Highway, 15.811°S 128.485°E, 26.i.2020, S. Ong; 2 males, Wuggubun Springs, Wuggubun Indigenous Community, 15.961°S 128.380°E, 7.ii.2020, S. Ong; 2 males, 40 km W of Kununurra, 6.i.1986, M.S. & B.J. Moulds; 1 male, AU.WA.DRK, Gibb R. Rd, at Durack R./ Bamboo Ck jct. 15º51.613’S 127º21.963’E, 240 m, 19.xi.2011, K. Hill, D. Marshall (DE). 2 males, 40 km W of Kununurra, 6.i.1986, M.S. & B.J. Moulds (LP). 1 male, Valentine Springs, Valentine Springs Rd, Kununurra, 15.720°S 128.652°E, 1.ii.2020, S. Ong, PMH Coll #CIC 2410; 2 males, 40 km W of Kununurra, 6.i.1986, M.S. & B.J. Moulds (PH). 15 males, 40 km W of Kununurra, 6.i.1986, M.S. & B.J. Moulds; 12 males (2 genitalia preps. BUR11, NTR1), 1 female, 40 km E of Durack R. x-ing, Gibb R. road, 29.xii.1991, M.S. & B.J. Moulds; 14 males, 8 km E of Durack R. x-ing, Gibb R. road, 30.xii.1991, M.S. & B.J. Moulds; 18 males (3 Simon Lab. vouchers 11.AU. WA.DRK.01, 11.AU.WA.DRK.02, 11.AU.WA.DRK.03, 11.AU.WA.DRK.05 in ethanol), 2 females, Gibb R. Rd, at Durack R./ Bamboo Ck jct. 15º51.61’S 127º21.96’E, 240 m, 19.xi.2011, K. Hill, D. Marshall (MSM). 8 males, Gibb R. Rd, at Durack R./ Bamboo Ck jct. 15º51.61’S 127º21.96’E, 240m, 19.xi.2011, K. Hill, D. Marshall (WAME 113417-113424) (WAM). NORTHERN TERRITORY: 5 males, 2 females, Gurrandalng [=Goorrandalng] camping area, Keep River Nat. Park, 15°52’S 129°03’E, 100 m, 4.i.1993, G. and A. Daniels (MSM). 5 males, 2 females, Gurrandalng camping area, Keep River Nat. Park, 15°52’S 129°03”E, 100 m, 4.i.1993, G. and A. Daniels (NTM).
Distribution and habitat (Figs 15b, 21). Known only from an area within 150 km of Kununurra in the far north-eastern corner of Western Australia. The most western locality is the Durack River on the Gibb River Road, and the most eastern is just over the Northern Territory border at Keep River. Adults are found in long grass that usually has a mixture of both live and dead leaves and is often found growing next to small water channels. Adults appear after the first rains in December and can be locally common through to at least mid February.
Adult description. Male (Figs 1a, 15a, 22a–d). Head brown, darkest around ocelli, paling towards eyes and often with a faint green tinge. Eyes in life pale tan. Postclypeus brown, similar in tone to that around ocelli. Anteclypeus brown, darkening towards apex. Rostrum brown, becoming black at apex; reaching bases of hind coxae. Thorax green dorsally, light brown ventrally. Pronotum often with (but sometimes lacking) a black or dark brown narrow fascia either side of midline, together these forming an inverted keyhole shape extending between anterior pronotal margin and pronotal collar; often irregular black or brown markings along sutures and extending laterally adjacent to the paranota and onto the pronotal collar lateral angles. Mesonotum with submedian and lateral sigilla black, the latter sometimes reticulate; scutal depressions black, and a black or dark brown mark between anterior arms of cruciform elevation that sometimes projects forwards in a lanceolate spike; cruciform elevation sometimes tending light yellowish brown. Forewing hyaline; costa light yellowish brown often with hints of green, most other venation on basal half also light yellowish brown; 2A+3A black adjacent to basal membrane; venation on distal half of wing dark brown or black; infuscation on veins forming bases of apical cells 2–5 and 7; distal ends of longitudinal veins forming apical cells 1–7 with an infuscated spot; basal cell tinted brown, often only on anterior half; basal membrane pale brown to pale pinkish orange. Hindwing venation dark brown to black except for very pale brown CuA, CuP, and 1A–3A; a narrow white plaga on 2A and a wide plaga on 3A, both reaching full length. Legs yellowish brown to dark brown, often with green tints; fore femora with spines short, the primary spine no longer than any other; meracantha dark brown basally becoming pale yellow distally. Opercula broad and rounded, not quite meeting or slightly overlapping, confined to margins of tympanal cavities; pale yellow with a large black suffusion on anterior distal half but not reaching apex. Abdomen with tergites brown, often darker or tending black on tergites 2 and 3; sternites yellowish brown to mid brown but always paler than tergites. Timbal covers similar in colour to tergite 2 but usually palest apically; reaching about half way across timbal cavity. Timbals as in generic description above.
Genitalia (Figs 22a–d). Uncus in lateral view gently curved, widest at about mid length and tapering on distal half to a bluntly rounded point; uncus in dorsal view barely tapered, the apex emarginate, the dorsal midline depressed.Aedeagus robust; basal plate in dorsal view terminating in a short, somewhat squared apical projection; two subapical ‘cerci’, one very long on left side protruding beyond thecal apex, the other ill-defined.
Female (Fig. 1b). Colouration and markings similar to male. Abdominal segment 9 brown on dorsal half, pale yellow on ventral half with a small dull black mark against ventral basal margin; apical spine black or tending so; ovipositor sheath distally black, projecting about 1.5 mm beyond apical spine.
Measurements. Range and mean (in mm) for 10 males, 9 females (includes smallest and largest specimens). Length of body (including head): male 15.6–17.3 (16.2); female (including ovipositor) 14.8–18.7 (16.5). Length of forewing: male 18.6–22.6 (20.6); female 17.7–20.5 (19.2). Width of head (including eyes): male 5.1–5.7 (5.4); female 4.8–5.5 (5.2). Width of pronotum (across lateral angles): male 5.6–6.2 (6.0); female 5.1–6.1 (5.8).
Distinguishing features. Illyria viridis sp. n. is closest to I. hilli in its overall green appearance and markings, and has somewhat similar male genitalia. It differs, however, in having the distal ends of the veins forming the apical cells each bearing an infuscated spot, in its distinctly swollen male abdomen and very large tympanal cavity the occupies half the length of the abdomen.
Song (Figs 23a–d). Recordings were examined only from the WA.DRK paratype location.
The male calling song is a continuous, slightly rattle-like call. Short syllables of generally 3–8 pulses are produced at a uniform rate of 23–27 syllables/s. The song oscillates between series of syllables of contrasting length, with syllable length slowly decreasing with a concordant drop in amplitude and then more suddenly returning to longer, louder syllables. The resulting phrases are about 4.5–7 s in duration. Occasionally, just as the shift to longer, louder syllables begins, short single pulses are produced between the syllables. Peak sound frequency varies slightly between 10–11.5 kHz, with a drop in the dominant frequency corresponding to the transition to longer syllables. Most sound energy is concentrated within the range 9.0–12.5 kHz. Sound intensity varies by a factor of 2 to 3 on the oscillogram scale.
Males sing both during the heat of the day and at dusk. Adults can often be plucked from grass stems while singing.
description: Published as part of Moulds, Max & Marshall, David C., 2022, New genera and new species of Western Australian cicadas (Hemiptera: Cicadidae), pp. 451-507 in Zootaxa 5174 (5) on pages 460-461, DOI: 10.11646/zootaxa.5174.5.1, http://zenodo.org/record/6986555