Isoperla obliqua Zwick, 1978

Murányi, Dávid, 2011, Balkanian species of the genus Isoperla Banks, 1906 (Plecoptera: Perlodidae), Zootaxa 3049, pp. 1-46 : 32-33

Isoperla obliqua Zwick, 1978 stat. n.

Isoperla tripartita obliqua Zwick, 1978 — Zwick 1978: 230 (original description of male).

Material examined: GREECE: Achaia prefecture: Ano Vlassia , Mts Erimanthos, Selinous Stream, 1000 m, 25.05.1992, leg. H. Malicky, det. G. Vinçon: 2m 2f ( HNHM; one penial armature prepared on slide) .

Diagnosis: This species is characterized by a coloured medial penial armature that is divided into an upper and a lower part. Its upper medial armature is further divided into diverging, tear drop-shaped left and right arms with a lower medial armature that is weakly subdivided. All scales on armatures are spike-like and the lateral penial armatures vestigial.

Complementary description: General appearence, dimensions, male and female abdomen: Similar to I. tripartita tripartita as redescribed above. Head and pronotal pattern of the examined specimens remind one of that depicted in Fig. 96, but with rugosities on the occiput.

Penis: Lobes and the distribution of non coloured scales, hairs and sensilla cannot be studied in detail because the specimens were collected without an everted penis. However, the narrow stripe of hydra-like scales, characteristic for the species group, can be detected. The medial penial armature is in agreement with the original description ( Zwick 1978: Figs. 72j, k). Lateral penial armatures are vestigial, consisting of only a few uncoloured spikelike scales.

Larva, egg: unknown.

Affinities: See I. tripartita tripartita above.

Ecology and distribution: The species was originally described from the Greek Euboea Island, Andros Island , the Peloponnes and the Greek mainland ( Zwick 1978). The species has not been referenced since its description. The known localities are submontane streams and spring outlets, the adults being caught in May, usually in common with a diverse community of stoneflies .

Remarks: The area of the species completely overlaps with I. tripartita tripartita , so I propose full species status herein. Nevertheless, as it was already stated in the original description ( Zwick 1978), transitional forms towards I. tripartita tripartita occur and the validity of the taxon requires further investigation.