Oecetis houghtoni, Blahnik, Roger J. & Holzenthal, Ralph W., 2014

Blahnik, Roger J. & Holzenthal, Ralph W., 2014, Review and redescription of species in the Oecetis avara group, with the description of 15 new species (Trichoptera, Leptoceridae), ZooKeys 376, pp. 1-83 : 32-39

Oecetis houghtoni sp. n. Figs 10, 11, 12, 34, 42, Map 2

Diagnosis.

Oecetis houghtoni is most similar to, and most likely to be confused with, Oecetis avara . At least in material from Minnesota it is distinctly darker in color, brownish, rather than yellowish or yellowish-brown, and has less distinct forewing spots (sometimes nearly absent). The 2 species can generally be identified by color attributes alone. However, there are other differences. In general, the ventral lobe of the inferior appendage is less projecting than in Oecetis avara and the angle it forms with the dorsal lobe tends to be somewhat rounded, without the “wrinkling” apparent in Oecetis avara , and the posterior margin of the dorsal lobe is somewhat angular. The latter character is subtle, but once noticed is very useful. The angle between the dorsal and ventral lobes is usually slightly acute or nearly at a right angle, and thus may be difficult to distinguish from the distinctly acute angle of Oecetis avara . The phallobase in Oecetis houghtoni is arched ventrally, but usually not as strongly deflexed apically as in Oecetis avara (this character is variable in both species). Also, the phallobase tends to be more uniformly sclerotized (not as sclerotized apically). In most specimens examined, the forewing chord is more narrowly spaced in Oecetis houghtoni than in Oecetis avara , often with the veins more or less diagonal (Fig. 34A), or with the s and r-m veins very closely spaced. Oecetis houghtoni also differs significantly from Oecetis avara in COI barcode sequence (Fig. 58). The possibility that this difference may represent unrecognized species diversity had already been commented on by Zhou et al. (2011).

Adult.

Forewing length: male (8.0-10.0 mm), female (6.2-8.3 mm). Color light brown (darker than Oecetis avara ). Antennae whitish with indistinct, narrow annulations at intersection of antennomeres. Forewing spots very small and indistinct; spots at base of discal and thyridial cells and base of fork V usually evident; veins of forewing chord narrowly spaced, usually more or less diagonal, either evenly spaced (Fig. 34A) or s and r-m veins slightly closer; chord with crossveins lightly pigmented; spots at apices of major veins either absent or very indistinct (usually not evident). Setae along veins in apical part of forewing mostly apically directed, not or only slightly laterally diverging. Fringe of setae along costal margin of forewing dense, short, not strongly projecting.

Male genitalia.

Segment IX very short, with elongate setae along posterolateral margin. Tergum X with narrow, deflexed mesal lobe, apex of lobe tapered, with small sensilla; lobe continuous basoventrally with short, paired lateral membranous projections. Preanal appendage relatively short, length about 2 times maximum width (shorter, on average, than Oecetis avara ), simple in structure, apical setae elongate. Inferior appendage with prominent rounded dorsal lobe and angularly projecting ventral lobe; projection of ventral lobe only moderately protruding, typically forming a somewhat acute angle with dorsal lobe, but varying to a somewhat obtuse angle, angle usually rounded, not noticeably “wrinkled’ at articulation; posterior margin of dorsal lobe characteristically angulate and somewhat mesally infolded; mesal margin of ventral lobe, as viewed ventrally (Fig. 10F), strongly bent near base; basomesal projection of appendage weakly rounded, with short, stiff setae; dorsal lobe with stout, mesally-curved setae on dorsal margin and stout, ventrally-curved setae on mesal surface. Phallobase very short, tubular basally, ventral margin curved, apex not strongly down curved, only moderately sclerotized; ventral apex, as viewed caudally, U-shaped (Fig. 10C). Phallotremal sclerite prominent, basally forming short tubular collar, ventral margin projecting, apex acute; asymmetrical lateral sclerite present.

Holotype.

Male (pinned), USA: Minnesota: Lake Co., Baptism River at State Hwy. 1, Eckbeck campground, 47°22.137'N, 91°13.767'W, 320 m, 24.vii.1996, Holzenthal & Huisman (UMSP) (UMSP000050387).

Paratypes.

CANADA: Ontario: Ottawa, Ottawa Champlain Rapids, 6.vii.1978, C.M. & O.S. Flint, Jr. 1 male (pinned) (NMNH); Ottawa River, 5 mi N Dunrobin, 45°28.1'N, 75°58.8'W, 25.vii.1996, C.M. & O.S. Flint, Jr., 1 male (pinned) (NMNH); Kearney, Magnetawan River, 23.viii.1983, O.S. Flint, Jr., 1 male (pinned) (NMNH); Killaloe, Brennans Creek, 18.viii.1983, O.S. Flint, Jr., 1 male (pinned) (NMNH); USA: Arkansas: Montgomery Co., Little Missouri River, Albert Pike, 28.viii.1980, E.J. Bacon, 15 males (alcohol) (UMSP); same locality, 19.ix.1980, E.J. Bacon, 1 male, 17 females (alcohol) (UMSP); same locality, 20.ix.1980, E.J. Bacon, 1 male, 6 females (alcohol) (UMSP); same locality, 24.ix.1981, E.J. Bacon, 53 males, 85 females (alcohol) (UMSP); Michigan: Cedar River, 25.viii.1937, L.R. Penner, 1 male (pinned) (UMSP); Minnesota: Aitkin Co., Snake river, Silver Star Road, 46°12.000'N, 93°15.000'W, 29.vi.2001, D.C. Houghton, 263 males, 287 females (alcohol) (UMSP); Aitkin Co., Swan River, nr. State Road 200, 47°00.5000'N, 93°15.500'W, 12.vii.2000, D.C. Houghton, 317 males, 302 females (alcohol) (UMSP); Aitkin Co., 15.vii.1938, D.G. Denning, 1 male (pinned) (UMSP); Anoka Co., Coon Creek, 13.vi.1937, D.G. Denning, 1 male, 3 females (pinned) (UMSP); Anoka Co., 27.vi.1938, D.G. Denning, 1 female (pinned) (UMSP); Becker Co., Pike Lake, Elbow Lake Road, 47°07.000'N, 95°31.333'W, 04.vii.2000, D.C. Houghton, 1 male (alcohol) (UMSP); Becker Co., Ottertail River, mi. 162, Hubbel Pond WMA, 16.viii.1982, N. Kirsch, 2 males, 7 females (alcohol) (UMSP); Beltrami Co., Shotley Bridge, County Road 111, 48°03.500'N, 94°31.667'W, 04.vii.2000, D.C. Houghton, 3 males, 1 female, (alcohol) (UMSP); Beltrami Co., Upper Red Lake, County Road 108, public access, 48°03.917'N, 94°42.167'W, 25.viii.2000, D.C. Houghton, 1 male, 1 female (alcohol) (UMSP); Carlton Co., Silver Creek, Jay Cooke State Park, 46°38.666'N, 92°21.000'W, 14.vii.2001, D.C. Houghton, 2 males, 2 females (alcohol) (UMSP); Cass Co., Big Rice Lake, State Road 06, 46°59.500'N, 93°57.333'W, 30.vi.2000, D.C. Houghton, 2 males (alcohol) (UMSP); Cass Co., Boy River, County Road 53, 47°04.667'N, 94°06.333'W, 30.vi.2000, D.C. Houghton, 319 males, 206 females (alcohol) (UMSP); Cass Co., Mabel Lake, Mabel Lake campground, 47°03.500'N, 94°04.000'W, 30.vi.2000, D.C. Houghton, 5 males, 7 females (alcohol) (UMSP); Cass Co., Shingobee River, County Road 83, 47°00.666'N, 94°40.000'W, 30.ix.2000, M.P. Monson, 11 males, 7 females (alcohol) (UMSP); Cass Co., Birch Bridge, County Road 132, 47°02.000'N, 93°52.000'W, 30.vi.2000, D.C. Houghton, 1 female (alcohol) (UMSP); Cass Co., Cass Lake, 30.vii.1935, R.H. Nagel, 1 female (alcohol) (UMSP); Cass Co., Cass Lake, 10.vii.1936, R.H. Daggy, 1 male (pinned) (UMSP); same locality, 19.vii.1936, R.H. Daggy, 1 female (pinned) (UMSP); Cass Co., 3-11.vii.1937, L.W. Orr, 1 male, 14 females (pinned) (UMSP); Clearwater Co., Iron Springs Bog Sci. Nat. Area, Sucker Creek, 47.253°N, 95.242°W, el 457 m, 13.viii.1988, M. Monson, 1 male (alcohol) (UMSP); same locality, 29.vi.1989, M. Monson, 1 female (alcohol) (UMSP); Clearwater Co., Itasca State Park, Mississippi River at County Road 117, 28.vi.1993, Holzenthal, 1 male, 1 female (pinned) (UMSP); Clearwater Co., Itasca State Park, 2.vii.1939, C.E. Nickel, 1 male (pinned) (UMSP); Cook Co., Temperance River, Sawbill Trail, 47°43.667'N, 90°52.834'W, 16.vii.2000, D.C. Houghton, 28 males, 40 females (alcohol) (UMSP); Cook Co., Superior National Forest, Temperance River at National Forest Campground, R.J. Blahnik, 1 male, 1 female (pinned) (UMSP); Crow Wing Co., Crow Wing Lake, State Road 371, 46°43.333'N, 94°21.500'W, 24.vi.2000, D.C. Houghton, 1 male (alcohol) (UMSP); Crow Wing Co., Little Pine River, Perry Lake Road, 46°37.000'N, 94°00.067'W, 20.viii.1999, D.C. Houghton, 25 males, 67 females (alcohol) (UMSP); Crow Wing Co., Pine River, County Road 11, 46°34.333'N, 94°02.000'W, 29.vi.2000, D.C. Houghton, 32 males, 3 females (pinned), 223 males, 120 females (alcohol) (UMSP) (NMNH); Douglas Co., Fairfield Creek, State Road 27, 45°52.333'N, 95°13.500'W, 23.vi.2000, D.C. Houghton, 1 male (alcohol) (UMSP); Douglas Co., Lake Carlos, Lake Carlos State Park, 45°59.500'N, 95°19.834'W, 23.vi.2000, D.C. Houghton, 3 males, 1 female (alcohol) (UMSP); Douglas Co., headwaters Long Prairie River, Lake Carlos State Park, 45°58.916'N, 95°19.67'W, 23.vi.2000, D.C. Houghton, 146 males & females (alcohol) (UMSP); Hubbard Co., Straight River, County Road 111, 48°52.333'N, 95°01.667'W, 03.vii.2000, D.C. Houghton, 142 males, 193 females (alcohol) (UMSP); Hubbard Co., Long Lake, County Road 06, public access, 46°51.500'N, 95°01.333'W, 03.vii.2000, D.C. Houghton, 1 female (alcohol) (UMSP); Hubbard Co., LaSalle Creek at County Road 40, 47°20.940'N, 95°09.900'W, el 425 m, 12.vi.1988, M. Monson, 17 males, 6 females (alcohol) (UMSP); same locality 25.vi.1988, M. Monson, 36 males 53 females (alcohol) (UMSP); same locality, 02.vii.1988, M. Monson, 31 males, 106 females (alcohol) (UMSP); same locality, 24.vii.1988, M. Monson, 127 males 67 females (alcohol) (UMSP); same locality, 26.vii.1988, M. Monson, 66 males 55 females (alcohol) (UMSP); same locality, 13.viii.1988, M. Monson, 113 males 42 females (alcohol) (UMSP); same locality 22.viii.1988, M. Monson, 17 males 34 females (alcohol) (UMSP); same locality, 10.ix.1988, M. Monson, 1 female (alcohol) (UMSP); same locality, 29.vi.1989, M. Monson, 162 males, 69 females (alcohol) (UMSP); same locality, 16.vii.1989, M. Monson, 108 males 97 females (alcohol) (UMSP); same locality, 27.vii.1989, M. Monson, 115 males, 35 females (alcohol) (UMSP); same locality, 13.viii.1989, M. Monson, 83 males, 49 females (alcohol) (UMSP); same locality 30.ix.1989, M. Monson, 1 male (alcohol) (UMSP); Itasca Co., Popple River, County Road 126, Chippewa National Forest, nr. Dora Lake, 47°43.546'N, 94°04.952'W, 10.vii.1999, D.C. Houghton, 1 male, 5 females (alcohol) (UMSP); Itasca Co., Bear Lake, headwaters Bear River, 47°40.634'N, 93°16.081'W, 14.vii.1999, D.C. Houghton, 2 females (alcohol) (UMSP); Itasca Co., Bear River, County Road 52, George Washington State Forest, 47°42.413'N, 93°15.424'W, 14.vii.1999, D.C. Houghton, 2 males, 3 females (pinned) (UMSP); Itasca Co., Deer Creek at County Road 230, 7 mi E Effie, 1 mi N Hwy. 1, 47°50.845'N, 93°29.333'W, 400 m, 29.vi.1996, Holzenthal et al., 26 males (pinned) (UMSP); Itasca Co., Big Fork River at Hwy. 1, 6.5 mi E Effie, 47°50.465'N, 93°30.156'W, 390 m, 28.vi.1996, Holzenthal et al., 10 males, 2 females (pinned) (UMSP); Itasca Co., outlet of Wabena Lake at County Road 49, ca. 11 mi N Grand Rapids, 411 m, 47.407°N, 93.485°W, R. Blahnik & F. Muñoz, 30 males, 3 females (pinned) (UMSP); Kittson Co., Caribou, 30.vi.1941, D.G. Denning, 1 male (alcohol) (UMSP); Koochiching Co., Black River, State Highway 11, 48°30.667'N, 93°48.000'W, 24.viii.2000, D.C. Houghton, 1 male, 2 females (alcohol) (UMSP); Koochiching Co., headwaters Black River, Fiero F.R., 48°25.888'N, 94°11.985'W, 11.vii.1999, D.C. Houghton, 2 males (alcohol) (UMSP); Koochiching Co., Black River, Indian Pines F.R., 48°27.986'N, 94°11.391'W, 11.vii.1999, D.C. Houghton, 2 males, 1 female (alcohol) (UMSP); Koochiching Co., Rainy River, confl. Little Fork River, State Highway 11, nr. International Falls, 48°31.174'N, 93°34.174'W, 12. vii.1999, D.C. Houghton, 64 males, 103 females (alcohol) (UMSP); Koochiching Co., Little Tamarac River, Lost River F.R., 48°04.634'N, 94°22.467'W, 13.vii.1999, D.C. Houghton, 3 males, 5 females (alcohol) (UMSP); Koochiching Co., Lost River, Lost River F.R., Pine Island State Forest, 48°05.320'N, 94°15.943'W, 13.vii.1999, D.C. Houghton, 1 male (alcohol) (UMSP); Koochiching Co., Big Fork River, State Highway 11, public access, Pine Island State Forest, nr. International Falls, 48°30.700'N, 93°42.754'W, el 244 m, 12.vii.1999, D.C. Houghton, 2 males (pinned) (UMSP); Lake Co., Gooseberry River, County Road 03, 47°10.000'N, 91°34.500'W, 11.vii.2001, D.C. Houghton, 87 males, 103 females (alcohol) (UMSP); Lake Co., W Branch Beaver River, County Road 3, 47°15.250'N, 91°22.834'W, 18.vii.1999, D.C. Houghton, 14 males, 2 females (alcohol) (UMSP); Lake Co., same data as holotype, 10 males (pinned) (UMSP); same locality, 30.vi.1991, R.J. Blahnik, 7 males (pinned) (UMSP); same locality, 11.viii.1991, Huisman & Holzenthal, 2 females (pinned) (UMSP); Lake of the Woods Co., Rapid River, County Road 98, 48°30.000'N, 94°39.500'W, 05.vii.2000, D.C. Houghton, 301 males 153 females (alcohol) (UMSP); Lake of the Woods Co., Zippel Bay State Park, 48°52.000'N, 94°50.000'W, 07.vii.2000, D.C. Houghton, 209 Males, 113 females (alcohol) (UMSP); Lake of the Woods Co., Moose Creek, County Road 01, 48°30.000'N, 94°36.000'W, 05.vii.2000, D.C. Houghton, 1 male 3 females (alcohol) (UMSP); Mahnomen Co., White Earth River, State Road 113, 47°10.667'N, 95°47.667'W, 04.vii.2000, D.C. Houghton, 583 males, 542 females (alcohol) (UMSP); Mahnomen Co., Little Elbow Creek, County Road 04, 47°12.000'N, 95°39.000'W, 04.vii.2000, D.C. Houghton, 3 males, 3 females (alcohol) (UMSP); Marshall Co., Middle River, County Road 04, 48°20.333'N, 96°49.000'W, 24.vii.2000, D.C. Houghton, 1 male (alcohol) UMSP); Mille Lacs Co., Lake Mille Lacs, Cove Bay, 46°06.667'N, 93°37.333'W, 28.vi.2000, D.C. Houghton, 1 male, 1 female (alcohol) (UMSP); Mille Lacs Co., Bradbury Bridge, County Road 103, 46°01.500'N, 93°41.500'W, 28.vi.2000, D.C. Houghton, 23 males, 30 females (alcohol) (UMSP); Mille Lacs Co., Rum River, Mille Lacs Kathio State Park, 46°07.000'N, 93°45.500'W, 28.vi.2000, D.C. Houghton, 287 males, 316 females (alcohol) (UMSP); Morrison Co., Platte River, County Road 35, 45°56.167'N, 94°14.917'W, 24.v.2000, D.C. Houghton, 81 males, 183 females (alcohol) (UMSP); Morrison Co., Pike Creek, Charles Lindberg State Park, 45°57.333'N, 94°23.500'W, 24.vi.2000, D.C. Houghton, 52 males, 27 females (alcohol) (UMSP); Morrison Co., Mississippi River, Charles Lindberg State Park, 45°57.000'N, 94°23.333'W, 24.vi.2000, D.C. Houghton, 1 male, 3 females (alcohol) (UMSP); Murray Co., Smith Lake, Lake Shetek State Park, 44°05.841'N, 95°41.473'W, 305 m, 01.viii.1999, D.C. Houghton, 1 female (pinned) (UMSP); Pennington Co., Thief River Falls, 20.viii.1941, D.G. Denning, 1 male, 20 females (alcohol) (UMSP); same locality, 18.vii.1941, D.G. Denning, 11 females (alcohol) (UMSP); Pine Co., Sand Creek, County Road 30, 46°07.667'N, 92°37.500'W, 28.vi.2001, D.C. Houghton, 35 males, 47 females (alcohol) (UMSP); Pine Co., Little Sand Creek, 1 mi E Cloverdale, 16.vii.1971, 6 males (alcohol) (UMSP); same locality, 8.viii.1971, 1 male (alcohol) (UMSP); same locality, 6.vii.1971, 1 male (alcohol) (UMSP); Pine Co., L. Pine Creek, State Road 18, 46°12.000'N, 92°59.500'W, 29.vi.2001, D.C. Houghton, 5 males, 17 females (alcohol) (UMSP); Pine Co., Big Pine Lake, State Road 18, 46°13.000'N, 93°01.500'N, 29.vi.2001, D.C. Houghton, 1 male, 1 female (alcohol) (UMSP); Pine Co., Kettle River, Banning State Park, 46°10.000'N, 92°50.000'W, 28.vi.2001, D.C. Houghton, 8 males, 4 females (alcohol) (UMSP); Pine Co. Kettle River, 9.viii.1991, L.J. Luedeman, 10 males, 11 females (alcohol) (UMSP); Polk Co., Red Lake River, US Route 75, 47°46.666'N, 96°38.000'W, 23.vii.2000, D.C. Houghton, 5 females (alcohol) (UMSP); Polk Co., Crookston, 7.vii.1935, D.G. Denning, 1 male, 2 females (pinned) (UMSP); same locality, 18.vii.1935, D.G. Denning, 1 female (pinned) (UMSP); same locality, 3.vii.1936, D.G. Denning, 1 female (pinned) (UMSP); same locality, 27.vii.1936, D.G. Denning, 1 female (pinned) (UMSP); same locality, 29.vi.1937, D.G. Denning, 1 male, 1 female (pinned) (UMSP); same locality, 4.vii.1937, D.G. Denning, 2 females (pinned) (UMSP); Ramsey Co., Lake Johanna, 6.vii.1937, D.G. Denning, 1 female (pinned) (UMSP); Ramsey Co., St. Paul, University golf course, A.A. Granovsky, 2 females (pinned) (UMSP); Ramsey Co., St. Paul, University Farm, 14.vii.1936, A.A. Granovsky, 1 female (pinned) (UMSP); Rock Co., un. spr., Mound Lakes, Blue Mound State Park, 43°43.000'N, 96°10.175'W, 07.vi.2000, D.C. Houghton, 1 male, 1 female (alcohol) (UMSP); Roseau Co., Roseau River, Winner F.R., 48°38.000'N, 95°29.000'W, 08.vii.2000, D.C. Houghton, 219 males, 167 females (alcohol) (UMSP); Roseau Co., Roseau River, Winner F.R., nr. Beltrami Island State Forest, 48°38.950'N, 95°28.967'W, 31.viii.1999, D.C. Houghton, 545 males, 858 females (alcohol) (UMSP); Roseau Co., Hayes Lake, Hayes Lake State Park, 48°38.083'N, 95°31.583'W, 08.vii.2000, D.C. Houghton, 3 males 3 females (alcohol) (UMSP); Roseau Co., Hansen Creek, Winner F.R., 48°38.000'N, 95°27.500'W, 08.vii.2000, D.C. Houghton, 4 males, 21 females (alcohol) (UMSP); Roseau Co., W Branch Warroad River, County Road 5, Beltrami Island State Forest, 48°44.867'N, 95°19.916'W, 31.viii.1999, D.C. Houghton, 1 female (alcohol) (UMSP); Saint Louis Co., Cloquet River, Bear Lake Road, 47°12.750'N, 91°56.500'W, 17.vii.2000, D.C. Houghton, 544 males, 513 females (alcohol) (UMSP); Saint Louis Co., Bear Lake, Cedar Bay campground, 47°12.500'N, 91°55.500'W, 17.vii.2000, D.C. Houghton, 3 males, 1 female (alcohol) (UMSP); Saint Louis County, Lake Cloquet River, Pequaywan Road, 47°06.833'N, 90°59.083'W, 17.vii.2000, D.C. Houghton, 146 males, 152 females (alcohol) (UMSP); Saint Louis Co., Smith Lake Spillway, Pequaywan Road, 47°08.000'N, 91°55.667'W, 17.vii.2000, D.C. Houghton, 41 males, 58 females (alcohol) (UMSP); St. Louis Co., Vermillion River, State Road 24, 48°07.400'N, 92°31.300'W, 20.vii.1999, D.C. Houghton, 1 male, 11 females (alcohol) (UMSP); St. Louis Co., Vermillion River, F.R. 491, 48°15.750'N, 92°33.500'W, 28.viii.2000, D.C. Houghton, 27 males, 21 females (alcohol) (UMSP); Saint Louis Co., Duck Creek, Echo Trail, 48°06.500'N, 92°03.667'W, 15.vii.2000, D.C. Houghton, 1 male (alcohol) (UMSP); St. Louis Co., St. Louis River, Jay Cooke State Park, 46°38.500'N, 92°21.000'W, 14.vii.2001, D.C. Houghton, 11 males, 32 females (alcohol) (UMSP); St. Louis Co., Coyote Creek, Pequaywan Road, 47°11.500'N, 91°52.000'W, 17.vii.2000, D.C. Houghton, 1 female (alcohol) (UMSP); St. Louis Co., Jenkins Creek, Town Line Road, 47°22.333'N, 91°57.333'W, 14.vii.2000, D.C. Houghton, 3 females (alcohol) (UMSP); St. Louis Co., Cadotte Lake, Cadotte Lake campground, 47°22.667'N, 91°54.917'W, 14.vii.2000, D.C. Houghton, 3 females (alcohol) (UMSP); Stearns Co., St. Cloud, 25.vii.1938, D.G. Denning, 3 males, 6 females (pinned) (UMSP); Todd Co., Birch Lake Creek, County Road 2, 46°47.666'N, 94°47.833'W, 16.vi.2000, D.C. Houghton, 1 male, 1 female (alcohol) (UMSP); Wadena Co., Shell River, Shell City Landing campground, 46°47.500'N, 94°56.500'W, 03.vii.2000, D.C. Houghton, 31 males, 34 females (alcohol) (UMSP); Yellow Medicine Co., Minnesota River, Mile 243.9, T115N, R38W, S28, 14.viii.1980, N. Potthoff, 2 males, 1 female (alcohol) (UMSP); Mississippi: Clark Allen Branch, Rt. 11, N Enterprise, 12.v.1988, C.M. & O.S. Flint, Jr., 2 males (pinned) (NMNH); Lauderdale, Chunky R., Dunn’s Falls Pk., 15 mi S Meridian, 13.v.1988, C.M. & O.S. Flint, Jr. 1 male (pinned) (NMNH).

Etymology.

We take pleasure in naming this species Oecetis houghtoni after Dr. Dave Houghton, Hillsdale College, Michigan, whose extensive survey work on the caddisflies of Minnesota provided the strongest evidence that this species is distinct from Oecetis avara .

Remarks.

While Oecetis houghtoni can be separated from Oecetis avara in the upper Midwest, USA, based on the characters listed, we were not always sure about specimens from other localities, due to the variation encountered. Once better understood, it is possible that this variation will be found to fall within the 2 species. However, it is also possible that additional undescribed species are represented. In particular, a form similar to Oecetis houghtoni in color and development of the forewing chord seems to be widespread in the Eastern United States and Canada, but differs in that the ventral lobes of the inferior appendages are very obtusely angled (Fig. 28A). This is possibly the form illustrated by Ross (1944) as Oecetis avara . We are not sure whether this form is referable to Oecetis houghtoni or represents yet another species. This form is discussed in more detail in the section on unassigned material following the species descriptions, but is not included among the paratype material. A somewhat similar form also occurs on the west coast of the United States.