Riethia (Kieffer 1917) (Diptera: Chironomidae) revised for the Austro-Pacific region Author Cranston, Peter S. text Zootaxa 2019 2019-07-25 4646 3 461 500 journal article 25594 10.11646/zootaxa.4646.3.3 4a3d31ca-e16b-4ccf-8407-231aa27702f1 1175-5326 3351058 25CA4A18-955F-4EA7-8978-E93032B54A2E Riethia kakadu Cranston sp.n. ( Figs 2E , 3C, H, M ) urn:lsid:zoobank.org:act: DAE50FEA-2EF3-4FB6-9027-AB14F10A6364 Riethia K1 Cranston 1996 ; 2000 . Type material. Holotype ♂ , AUSTRALIA , Northern Territory , Kakadu N.P. , Radon Spring, 12°45’S 132°55’E , 13–14.iv.1989 ( Cranston ) #2206 ( ANIC ) . Paratypes ): 3♂ , as holotype ; ♂ , Kakadu N.P., Coronation Hill, S. Alliga- tor R., 13°35’S 132°26’E , 4–5.vi.1988 ; ♂ , Western Australia , Kimberleys , Adcock Gorge , 35 km SW Mt. Barnett , Gibb River Rd. [ 16°55'S 125°46'E ] E[ucalyptus] camuldulensis, ' Lux' , 13– 14.8.1995 , leg. M. Baehr ( ZSM ) . Other material (collected Cranston , deposited ANIC, unless otherwise stated, Pe excluded due to association by co-location only): 4 Pe , as holotype , 3 Pe as holotype except 6.vi.1988 ; Pe , Litchfield National Park , Petherick’s Rainforest , 13°07’S 130°39’E , 6.viii.1990 ; Pe, Coronation Hill, S. Alligator R., Gimbat spillway, 13°34’S 132°35’E , 19–20.iv.1989 ; 2 Pe , 13°10’S 130°41’E , Litchfield Park , Wongi Falls , 6.viii.1990 ; Pe, Koolpin Gorge, 13°30’S 132°35’E , 15/ 16.v.1992 , #2213; Pe, Katherine Gorge, below gorge #1, 14°20’S 132°25’E , 21–22.v.1992 ; Pe, same except gorge #1, 14°18’S 132°26’E , 21.v.1992 . Identified on morphology as R. cinctipes , but possibly R. kakadu : Northern Territory , 4L, Kakadu N.P., Burdulba Ck., 5.i.2007 (Hanley et al .) ( MV NT11 B1R1-4 , all 3i ) . Description. Male . Thorax yellow, with vittae weakly indicated as darker yellow; legs pale, without banding or with slight darkening of subapical femora. Wing membrane unmarked, veins pale. Setae of TIX fine, long, covering tergite. Gonostylus not broadened at junction with gonocoxite, which bears only simple setae. Superior volsella ( Fig. 2E ) covered in microtrichia with 1 long seta near base of digitus, posterior projection well developed, setose, melding into inferior volsella; digitus medially-directed, narrow, apically rounded, devoid of microtrichia, with 2 long simple setae, 1 towards base, 1 nearer apex; inferior volsella strong, with 5–7 pectinate scales and several simple setae. Pseudovolsella a strongly protruding tubercle with 3–4 proximated long setae ( Fig. 2E ). Mensural features as in Table 1 . Female unknown. Pupa (putative). Mid-brown, with darker brown dorsal thorax, anterior wing sheaths and lateral apophyses on abdominal segments V–VIII; comb brown. Cephalothorax rugulose with multiple rows of small tubercles along line of eclosion ( Fig. 3C ). Abdomen ( Fig. 3H ) with uninterrupted hook row occupying 40% of tergite width, conjunctival spinule bands on III and IV medially interrupted; pedes spurii B well developed; vortex strong. Tergite II with armament restricted to small triangular area anterior to hook row, without any indication of anterior transverse band, TII–VI with hour-glass shaped armament, TVII with strong anterior creases terminating without spinule; TVIII with microspinules anteriorly. Taeniate setae 3, 4, 4, 5, on VIII L 3–5 clustered. Comb ( Fig. 3M ) with 1 stronger spine, 2–3 weaker posteriorly-directed spines. Anal lobe with 45–50 +/- biserial taeniae. Larva unknown. Etymology. From the main location, Kakadu, the federally managed national park. To be treated as a noun in apposition. Diagnosis. The adult male has only simple setae on the gonostylus and the superior volsella, lacks pectinate scales. The digitus of the superior volsella lacks pectinate setae and seems characteristically narrow from the base, bearing only 1 inner and 1 outer seta. The pupa, which is associated only by co-occurrence, has an undivided hook row, lacks a conjunctival band on TV, and has the conjunctival rows on III and IV clearly divided medially. Remarks . No molecular data are available: specimens collected for the project did not produce DNA. DIstribution and Ecology. R. kakadu is known from northern Australia , in the areas of seasonal monsoonal rainfall. Most specimens have been collected in Kakadu and Litchfield National Parks which preserve some of the best quality waterways in northern Australia .