Isoperla roguensis Szczytko & Stewart, 1984

Sandberg, John B. & Kondratieff, Boris C., 2013, The Isoperla Of California (Plecoptera: Perlodidae); Updated Male Descriptions And Adult Keys For 18 Western Nearctic Species, Illiesia 9 (5), pp. 34-64 : 55

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Isoperla roguensis Szczytko & Stewart


Isoperla roguensis Szczytko & Stewart

( Figs. 14 View Figs a-d, 20 View Figs e)

Isoperla roguensis Szczytko & Stewart 1984 .

Holotype ♂, Oregon, Curry County, mouth of Rogue River.

Isoperla karuk Baumann & Lee 2009 . View Cited Treatment

Holotype ♂, California, Humboldt County, Klamath River @ junction of Aikens Creek . Syn. Sandberg, 2011b.

Male. Aedeagus: sclerotized posterior process present; body of aedeagus with one posterior lobe, one large dorsal lobe, and one anterior lobe ( Fig. 14a View Figs ); one bulbous and usually bi-hemispherical shaped patch of spinulae above sclerotized process and a small pair of spinule patches placed laterally ( Figs. 14 View Figs a-c); sclerotized process length approaching 0.5 mm, blade-like in lateral view ( Fig. 14a View Figs ), distal margin expanded and slightly membranous in posterior view ( Fig. 14b View Figs ), shape of distal expanded margin variable, and narrow proximal portion of sclerotized process usually inverted inside posterior aedeagal membrane. Abdominal terga 8-9, 9, 9-10: without stout spinulae or long stout setae. Posterolateral margins of at least abdominal segment 8 with scale-like setae clustered in brushes of several setae. Paraprocts: curved dorsally, length if straightened subequal to combined first and second cercal segments, tapering abruptly to tiny sharp apices ( Fig. 14c View Figs ). Vesicle: rounded lobe, widest at base with broadly rounded apical margin ( Fig. 14d View Figs ).

Isoperla roguensis shares similar characters with the species of the I. marmorata complex ( Table 1 View Table 1 ). See comments under I. fulva . Three distinct spinule patches distinguishes this species. Recently, Sandberg (2011b) placed I. karuk Baumann & Lee 2009 as a junior subjective synonym.

The previously described everted anterior tubelike lobes ( Szczytko & Stewart 1984, fig. 55) remained inverted after live eversion, their positions indicated by a pair of small inverted areas of membrane (openings). After clearing in KOH, the internal tubelike processes were visible with openings along anteroapical margin ( Fig. 20e View Figs , ventral aspect provided clearest view).

Additional Material Examined. CALIFORNIA, Plumas Co., MF Feather River, FR 12N61X access off Hwy 70, 10.5 mi (16.9 km) SE Quincy, 39.86453°N, 120.76138°W, 18/ VI /2013, J.L. York, 1♂, 1♀ ( JBSC); GoogleMaps Jamison Creek, 1.6 mi (2.6 km) E Two Rivers exit off Hwy 70, 39.813°N, 120.6821°W, 19/ VI /2013, J.L. York, 1♀ ( JBSC). GoogleMaps


Mykotektet, National Veterinary Institute














Isoperla roguensis Szczytko & Stewart

Sandberg, John B. & Kondratieff, Boris C. 2013

Isoperla karuk

Baumann & Lee 2009: 55

Isoperla roguensis

Szczytko & Stewart 1984: 55