Riethia stictoptera Kieffer

(Figs. 1E, 2K, 4D, 4H, 5B, C, I, 6N)

Riethia stictoptera Kieffer 1917: 203

Riethia astictica Kieffer 1917: 205 . Synonymy by Freeman 1961: 678.

[All types of both species, MNH (Musei Nationalis Hungarici, Budapest, Hungary) believed lost by Freeman 1961; not found since].

Material examined (collected Cranston, deposited ANIC, unless otherwise stated): AUSTRALIA: Queensland ♂, McIlwraith Range, 15 km WNW Bald Hill, [estimated 13°44’S 143°20’E], 27.vi.–12.vii.1989 (Naumann) #2103 ; 1♂, 8Pe, nr. Mareeba, Davies Ck., 17°01'S 145°35'E, 17–18.xii.1997, #2104–5, 3 Pe, 19–20.vi.1997 ; 3 Pe, 27– 28.viii.1997, 8 Pe, 17–18.xii.1997 ; 4 Pe, Palmerston N.P., Learmouth Ck., 17°35'S 145°42'E, 8–9.iv.1997, #2107 ; Le /P, nr Cardwell, 5 Mile Ck., 18°19.41'S 146°02.55'E, 17.xii.1997, #2110 ; ♂, Lawn Hill N.P., Musselbrook, Am- phitheatre, 18°21'S 133°51'E, 13.v.1995, #2108; Le / Pe / ♀, Paluma, Birthday Ck., 1.x.1998 (McKie) ; Pe, unnamed ck. s. of Paluma, 19°01’S 146°13’E, 25–26.iii.1998 ; Pe, Eungella N.P., Dalrymple Rock Rd., 950 m a.s.l., 21°02’S 148°34’E, 22.iii.1998.

New South Wales: Pe, Chaelundi S.F., Chandlers Ck., 30°02.22'S 152°29.26'E, 11.iv.1996, #2132; Pe, Barrington Tops, Dilgry R., 31°54'S 151°34'E, 14.iv.1990, #2119; ♂ (mounted from pinned by Cranston), Hornsby, 9.x.1958, at light (D.J. Lee) det. P. Freeman 1958 ; Pe, Farnworth Ave., Megarritys Ck., 33°53.10'S 150°36.30'E, 7.v.1993 (' AWT ’), #2154; Pe, Scotchey’s Ck., Lachlan Ck., 33°54'S 151°27'E, 7.v.1993 (' AWT ’), #2154; Pe, Belmore Falls, Barrengarry R., 34°38'S 150°33'E, 16.xii.1992, #2122 ; 3Pe, 3.iv.1991; Pe, Taralgo Ck., 34°22′S 149°54′E, 8.x.1991 (Drayson) #2136; ♂, 12 m. west of Euston, 34°45’S 142°45’E, AN#28, 18.xii.1967 (Nankivell & Gassner) ; Pe, nr. Tarago, L. Bathurst, e. shore (the Morass), 35°03′S 149°44′E, 16.x.1993, #2130; 3Pe, Endrick R., 6 km. E. of Nerriga, 35°05′S 150°08′E, 1.ix.1988, #2116; Shoalhaven R., 2Pe, Hillview, 35°11'S 149°57'E, 17.iii.1992, #2127; ♂, Windellama, 35°21'S 149°44'E, 17.ii.2019 ; Le / Pe / ♀, Warri Bridge, 35°21'S 149°44'E, 28.i.1992 ; 4Pe, 31.iii.1991, #2123; Pe, 17.iii.1992, #2125; 3Pe, Monga S.F. [N.P.], Mongarlowe R., 35°23'S 149°55'E, 2.ii.1991, #2120; Pe, Ballalaba Bridge, 35°34'S 149°47'E, 2.ii.1991, #2124; Le/Pe, Currowan S.F., Cabbage Tree Ck., 35°34'S 150°02'E, 30.iii.1994, #2128,9; 5 Pe, 21.i.1999 (MVAUS09 CTC#); Pe, Kosciuszko N.P., Yarrangobilly R., 35°44'S 148°29'E, 15.i.1991, #2133; Pe, S.W. Araluen, Deua R., 35°45'S 149°57'E, 9.xii.1990, #2118; Pe, same except 29.iii.1988, #2117; 6Pe, Kosciuszko N.P., 3 Mile Dam, 25.xii.1991; #2134; ♂, 6 m. north of Narellan, 35°59'S 145°55'E, AN#28.1, 13.xii.1963 (Martin) ; Albury, Murray River, Pe, Union Bridge, 36°05'S 146°58'E, #2150, P ♂, 30.i.1991 (Cook) ; 8Pe, ‘Station 6’, 36°06'S 147°01'E, 26.vii.1989 (Taylor/Cook) #2151–2; Pe, Noreuil Park, 36°05'S 146°56'E (Cook), #2138, Le/Pe/ ♀, 24.i.1990, #2139; c. 50Pe, Waterworks, 36°07'S 146°54'E, vi.–1990 – iv.1991 (Cook) # 2140–49; Le / Pe / ♂, ‘ Corp’ reared’ (? Cook); Mt. Imlay, Wallagaraugh R., 37°15'S 149°41'E, 13.i.1994, #2135.

ACT / NSW: Jervis Bay, L. McKenzie, 35°09'S 140°41'E, 19.xii. 199 7, #2115; 13Pe, 7.ix.1996 (Wright); Pe, 28.iv.1997; Pe, 12.ix.1997; 1 Pe, 4.i.1998; Pe, 7.ii.1998.

ACT: ♂ (slide from pinned by Cranston), Gungahlin, 17.i.1959 (A.L.Dyce), det. Freeman 1960 ; L. Burley Griffin, Lotus Bay, 35°17'S 149°08'E, 29.xii.1991 (Rosewarne); #2114; 2Pe, below Cotter dam, 35°21'S 149°56'E, 7.xi.1987; #2111; Pe, Namadgi N.P., Orroral R., 35°39'S 149°59'E.

Victoria: Wodonga, Middle Ck., Pe, Down St., 36°10'S 146°52'E 22.i.1990 (Cook) #2160; 3 Pe, Beechworth Rd, 36°15'S 146°50'E (Cook) #2159; Pe, Boyes Rd., 7.xii.1989 (Cook) ; Le / Pe / ♀, Melbourne, Botanic Gardens, 37°50'S 145°00'E, 4.viii.1971 (Martin) ; Le/Pe/ ♂, Belgrave Reservoir, 37°55'S 145°21'E, 23.vii.1969 (Martin); Le/Pe/ ♂, Lilydale, 37°55’S 150°10’E, L. coll. 11.vii.1962, em. 7.xi.1962 (Martin); Le/Pe/ ♀, same except L. coll. 16.vii.1962, em. 25.x.1962; ♀, Werribee R., 37°55’S 145°40’E, 21.xi.1985, L. coll. 21 xi.1995, em. 27.x.1962 (Martin); 1♂, Yarra River, 2km S. Wonga Park (Neboiss), 23.ii.1976 ; Pe, Swan L., 38°12'S 141°19'E, 20.xii.1996 (Wright).

Tasmania: ♂, Flinders Island, Lady Barron, Scott’s Lagoon, AF 1#3.2, 40°10’S 148°22’E, 11.ii.1976 (Martin & Lee); Le/Pe/ ♂, Table Cape, 7km n.w. Wynyard, 40°56’S 145°41’E (Martin) #2171; 2Pe, Waterhouse CA, Little Waterhouse L., 40°52’S 147°36.5’E, 22.iii.1997 (Wright, Swanson) #2309; 10Pe, nr Weldborough, Nothofagus Forest, 41°10’S 147°54’E, 20–25.iii.1993 (Trueman et al.). #2181–2 ; Cradle Mt. – L. St Clair N.P., Pe, L. Ayr, 41°49’S 146°03’E, 25.i.1990, #2169 ; ♂, Cradle Mt N. P., 41°41’S 145°50’E, AT#27.4, 18.x.1972 (Martin); Pe, West Coast Ranges, L. Selina, 41°53’S 145°36’E, 27.iii.1997 (Wright, Swanson) #2310; Pe, Central Plateau, nr. L. Ada, 1160 m a.s.l., 41°53’S 146°25’E, 15.iii.1997 (Wright) ; ♂, L. Leake, 42°00’S 147°48’E, AT#29.1, 21.x.1972 (Martin); Le/ P., L. St Clair (Martin, Timms) #2169; Pe, L. St Clair, 42°06’S 146°11’E, 19.i.1990, #2173; ♂, Le/Pe/ ♂, Penstock La- goon, 13 miles S. Miena, 42°05’S 146°46’E, 1.x.1971 (Martin); 2Pe, Forgotten L., 980 m a.s.l., 42°06’S 146°07’E, 25.iii.1997 (Wright) #2311; ♂ (pharate), Tooms L., 28 km. south-east of Ross, 42°19’S 148°10’E,AT#18.1, 12.x.1972 (Martin & Timms); Pe, Mt. Field N.P., Backhouse Tarn, 1140 m a.s.l., 42°40’S 146°34’E, 7.ii.1992, #2174 ; Pe, L. Seal, 900 m a.s.l, 42°40’S 146°35’E, #2180; 3Pe, 1♂, L. Fenton, 1006 m a.s.l,, 42°40’S 146°37’E, #2178, 9; 2 Pe, L. Dobson, 1040 m a.s.l,, 42°41’S 146°35’E, #2177; L, 2 Pe, Fairy Tarn, 940 m a.s.l,, 42°42’S 146°35’E, 7.ii.1992, #2175–6; Pe, Beatties Tarn, 970 m a.s.l., 42°42’S 146°48’E (Wright) #2313.

South Australia: 5 Pe, Ewens Ponds, 38°01'S 140°49.5'E, 19.xii.1996 (Wright) #2307; 4Pe, Mount Gambier, L. Edward, 37°37.6'S 140°36.2'E, 22.xii.1996 (Wright), #2308; Pe / ♂, 7 m. depth, 19.viii.1975 (Martin, Canning); #2167.

Western Australia: 3♂, Kimberley, Synnot Ck., CALM site 25/1, 16°31’S 125°16’E, 17–20.vi.1988 (Weir) #2102.

Northern Territory: 5♂, 1♀, Kakadu N.P., Radon Spring, 12°45’S 132°55’E, 13–14.iv.1989, #2095; ♂, Boro- alba Creek Springs, 19 km. NE by E. Mt Cahill, 22.dec.1972, D.H. Colless, at light; ♂, Graveside Ck., 13°18’S 132°32’E, viii.1989 (Dostine) #2098 ; Pe, Arnhem Land, nr. Narbaluk, Cooper Ck., 12°18’S 133°20’E, 27.v.1988, #2099; Pe, W. MacDonnell Range, inner Serpentine Gorge, 23°35’S 132°31’E, 8.iii.1995, #2101; 2Pe, Serpentine Gorge, 23°41’S 133°43’E, 27.v.1992, #2100.

Other material. Le/Pe/ ♂, Victoria, Emu Bottom (Martin) AV.141 (ZSM), det. Riethia stictoptera by Martin, confirmed M. Spies (pers. comm. 2019).

Description. Male. Thorax brown, with distinctive darker vittae. Legs pale with brown bands across femoraltibial junctions, at apices of tibia and tarsomeres 1–3, and all of tarsomeres 4–5; abdomen with brown transverse bands on segments 2–4 or 5. Wing membrane darkened over forks of R and FCu. TIX setae fine, long medially, shorter laterally, arranged into two closely approximated clusters. Genitalia (Fig. 1E) with uniquely shaped gonostylus, triangular, tapering medially to narrow and slightly hooked point, bearing only simple setae. Superior volsella (Fig. 2K) large medially directed lobe, with microtrichia and macrotrichia, without posterior projection. Inferior volsella separate from superior volcella, fused to inner margin of gonocoxite excepting short free section, with long simple setae, without pectinate scales. Pseudovolsella absent. Mensural features as in Table 1.

Female. Pigmentation as in male, AR 0.35, LR 1 1.0–1.05.

Pupa. Brown with darker dorsal thorax, anterior wing sheaths and lateral apophyses on all abdominal segments; comb brown. Cephalothorax with crenulate frons without warts, thorax rugose with multiserial tubercle rows on anterior dorsum. Hook row on II continuous, occupying c 45–50% tergite width, with continuous conjunctival spinule bands on III–IV. Pedes spurii B well developed on II, vortex large. Abdomen (Fig. 4D): tergite II with small triangular area of armament narrower than and just anterior to hookrow, without anterior spines, TIII–V with armament more or less rectangular, quite dense, with anterior transverse band at least as broad and of larger spinules than of posterior armament, TIII–V with strong anterior spinules and attenuated triangular medioposterior area; TVI with anterior ovoid area slightly separated from posterior area, TVII and VIII with modest microspinulation anteriorly. Taeniate setae V–VIII 3, 4, 4, 5, on VIII with L 3–5 clustered with respect to L 1–2. Comb (Fig. 4H) with 1 stronger, triangular spine directed postero-medially, 2–3 weaker inner spines. Anal lobe with 55–65 taeniae in disorganised biserial row.

Larva. Head capsule yellow with dark postmentum and broad almost black occipital margin; mentum (Fig. 5B) and 4 inner mandibular teeth (Fig. 5C) golden-brown. Clypeus (Fig. 6N) oval, wider anteriorly with somewhat flared anterolateral lobes; clypeal setae placed near to lateral margin. Inner margin of mandible with one broad lobe near insertion of seta subdentalis and 3 spines near mid-point of mola. Antenna (Fig. 5I) with AR 1.2–1.4; 3 rd segment much longer than 2 nd, with conventional wall (not thinned as in other taxa with long 3 rd segment). Ventromental plates 6–17% wider than mentum width. Mensural features as in Table 2.

Diagnosis. The combination of banded legs and unique gonostylus morphology is diagnostic. The short gonostylus fused to, and uncertainly separated from the gonocoxite, tapers abruptly to a postero-medially directed point, and bears only simple setae.

The pupa of R. stictoptera is much less distinctive. It has a continuous hook row and conjunctives with continuous spinule rows restricted to III, IV with V bare. Tergite II is almost free of spinules, with, at most, postero-medially of small spinule area, narrower than the hook row. DIfferentiation from a rather similar pupa of R. plumosa can be made on the larger spinule area on tergite II of R. plumosa and lack of a pedes spurii B.

The larva of Riethia stictoptera has a characteristically darkened prementum but pale genae, an antennal ratio of c. 1.4 and the clypeus variably broadened anteriory (Fig. 5M).

Remarks. The gonostylus shape of this species is unique and although the gonostylus illustrated by Kieffer (1917: Fig. 6b) is folded back on top of the gonocoxite, the diagnostic shape can be inferred.

A recent paper concerning Manoa by Qi et al. (2017) recognises two different barcode DNA sequences for R. stictoptera suggesting a misidentification in database(s). The author of sequence CAUS02310, identifies the vouchered larva as a species of Kiefferulus, and not Riethia (Dr Jon Martin, Melbourne, pers. comm.). As stated under R. azeylandica above, the larval voucher MV903 (Cranston et al. 2010) identified as R. stictoptera is corrected here to R. azeylandica (q.v.).

Distribution and ecology. Riethia stictoptera is the most widespread and pollution tolerant of species of Riethia . Although the only Western Australian record is from the Kimberley (the n.w. of the state), the species occurs widely across the border in Northern Territory including the ‘red centre’ and in the centre of Queensland’s Cape York Peninsula. In eastern Australia, R. stictoptera is found from 13°S to central Tasmania at 42°S and westwards in South Australian lakes. This species is found in a diversity of standing waters from ornamental pools, ponds, lowland billabongs to upland oligotrophic tarns. It is found also in large nutrient-enriched rivers such as the Murray River between Victoria and New South Wales.