A NEW SPECIES IN THE RHEOCRICOTOPUS (R.) EFFUSUS GROUP FROM CANADA WITH A REVIEW OF THE NEARCTIC SPECIES OF RHEOCRICOTOPUS AND PARAMETRIOCNEMUS (CHIRONOMIDAE: ORTHOCLADIINAE) Abstract Author Namayandeh, Armin Taxanama Corp., 25 Mabelle Ave, Toronto, ON, M 9 A 4 Y 1, Canada. a.namayan@taxanama.com Author Beresford, David V. Department of Biology, Trent University, Peterborough, Ontario, Canada. davidberesford@trentu.ca text CHIRONOMUS Journal of Chironomidae Research 2018 2018-12-27 31 16 29 journal article 53576 10.5324/cjcr.v0i31.2531 45286bc4-05f8-4be7-823f-274ae690fd76 2387-5372 7994948 Parametriocnemus hamatus ( Johannsen, 1934 ) ( Figs 1a–e ) Material examined. Parametriocnemus ( 1 ♂ ), Old Man Joe Mt. (No such location was found in Québec), Québec, 26 April 1968 , Collected by D. R . Oliver, No. CH 767 Diagnostic characters. Virga with 2–3 long narrow branches. AnP with inflated basal 1/2 to 2/3 with 4 stout setae on each side. IVo narrow and apically hooked. Gc with large projecting CD. Male (n=1). Total length = 3.2 mm Coloration of slide-mounted specimen : Male head and thorax light brown, abdomen golden-brown, halter hyaline to slightly golden, and wing golden-brown. Head. Antenna ( Fig. 1a ), with 13 flagellomeres, ultimate flagellomere (L = 606 μm) with apical setae (L = 35 μm); AR = 1.3. Eyes bare, with parallelsided dorsomedial extension ( Fig. 1b ). Tentorium L = 147 µm ( Fig. 1b ). Four coronal setae, six orbitals in single row on each side, Clypeus squared (L = 64 µm, W = 68 µm), bearing nine setae. Palpomeres p 1–5 , lengths (µm): 36, 42, 141, 143, 207; p 3 with 2 sensilla chaetica. Thorax. As in Fig. 1c . Antropronotals 11, uniserial; prealars 6, uniserial. Scutum with six setae in single row. Wing. Wing with fine punctation and hairs covering most of membrane ( Fig. 1d ). L = 2.1 mm , W = 0.6 mm . R with 24 setae, R 1 with 15, R 4+5 with 60 setae. Costa extends pass R 4+5 . R 4+5 distal to M 3+4 . Cu curved. Legs. Fore legs with two spurs (Ls = 42 µm, 30 µm), mid tibia with two spurs (Ls= 34 µm, 24 µm) and hind tibia with 2 spurs (Ls = 59 µm, 19 µm) and comb with 12–13 stout setae. Pseudospurs are absent. Mid and hind femurs with keel. Pulvilli reduced. Lengths and proportions of legs in Table 1 . Hypopygium . As in Fig. 1e . Segment IX bilobed. Virga present with 2–3 long narrow branches. Anal point L = 61 µm. Superior volsella tapered. Inferior volsella narrow and apically hooked-shaped. Gonocoxite longer than wide (L = 203 µm, W = 85 µm) with cluster of long setae medially just below the inferior volsella. Gonostyle more or less rectangular; crista dorsalis large triangular-shaped and strongly projecting above dorsal margin; megaseta L = 13 µm. HR = 3.8, HV = 2.4. Remarks. The species was first described by Johannsen, 1934 as Metriocnemus hamatus and indicated its close relationship with Meteriocnemus lundbecki Johannsen differing from the latter only in coloration and hypopygium. Sublette (1967) re-described the species as Paraphaenocladius hamatus (Joh.) with illustration of the male hypopygium.