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Lateral view of a Female Hexagenia limbata (Ephemeridae) (Hex) Mayfly Dun from the Namekagon River in Wisconsin
Hex Mayflies
Hexagenia limbata

The famous nocturnal Hex hatch of the Midwest (and a few other lucky locations) stirs to the surface mythically large brown trout that only touch streamers for the rest of the year.

Dorsal view of a Sweltsa (Chloroperlidae) (Sallfly) Stonefly Nymph from the Yakima River in Washington
This species was fairly abundant in a February sample of the upper Yakima.
27" brown trout, my largest ever. It was the sub-dominant fish in its pool. After this, I hooked the bigger one, but I couldn't land it.
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Stonefly Species Oroperla barbara (Gilltail Springflies)

Species Range

Physical description

Most physical descriptions on Troutnut are direct or slightly edited quotes from the original scientific sources describing or updating the species, although there may be errors in copying them to this website. Such descriptions aren't always definitive, because species often turn out to be more variable than the original describers observed. In some cases, only a single specimen was described! However, they are useful starting points.

Source: A Compendium Of Distributional Records For Oroperla Barbara Needham, 1933 (Plecoptera: Perlodidae), With Additional Documentation Of Reproductive Morphology And Biology

Adult habitus [Previously described by Jewett (1966)]. Male forewing length 15.0 mm (n = 1); female forewing length 19.0 - 20.5 mm (n = 3). Body dark brown, wings transparent with dark veins. Head dark brown with yellow markings; pronotum dark with a narrow, median yellow stripe. Antennae brown, cerci pale brown (Fig. 1). Abdominal gills present on ventrolateral corners of segments 1 - 7 (Fig. 9). Male epiproct and 10 th tergal complex [Previously described by Jewett (1966)]. Hemiterga of tergum 10 attenuated to form digit-like curved structures (Fig. 3). Black, Y-shaped, prominent epiproct anchor located anteromedially between hemiterga, and a large membranous cowl extends posteriorly enclosing epiproct. Epiproct bent sharply at a near right angle at posteroventral region of cowl (Fig. 4); most of epiproct very darkly sclerotized within cowl, but a short apical section lacks strong sclerotization. Much of epiproct surface covered with fine, densely packed setae. Epiproct tip in lateral aspect slightly excavated and not quite as wide as the more basally located and heavily sclerotized section. In dorsal aspect, a pair of darkly sclerotized paragenital plates are imbedded in the membranous cowl. Lateral stylets not evident. Aedeagus glabrous and recurved over terminal abdominal segments (Fig. 8). Dorsal aspect narrow, expanding into large, lateral lobes, narrowing abruptly with a rounded apex (Fig. 7). Lateral aspect with relatively constant width from base to anterior lobes, apex pointing downward and terminating in rounded tip (Figs. 8 - 9). Female subgenital plate [Previously described by Siegfried et al. (1977)]. Subgenital plate broad basally, narrowed apically and bearing a variably shaped shallow median notch (Figs. 5 - 6). Most of sternum 9 membranous, but posterior margin bearing a slender, black, transverse sclerite. Midlateral membranous field of sternum 9 also bearing a pair of subtriangular sclerites.

Egg (n = 8) [Previously described by Siegfried et al. (1977) and Stark & Szczytko (1984, 1988)]. Total length 623 µm, egg body length 561 µm, egg collar length 62 µm, egg diameter 419 µm, collar diameter 129 µm (Figs. 10 - 12). Chorionic surface covered throughout with hexagonal follicle cell impressions (FCI) (Figs. 10 - 15). Thick FCI walls surround a single, or a pair of pits (Fig. 15). FCI width near micropylar region 16 - 19 µm. Micropyles form irregular rows near mid-length; orifices small and often surrounded by rosettes composed of modified FCI’s (Fig. 15). Anchor hat-shaped with turned up brim (Fig. 13).

Start a Discussion of Oroperla barbara

Stonefly Species Oroperla barbara (Gilltail Springflies)

Species Range
Common Name
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