BackgroundStem-relatives of many winged insect orders have been identified among Pennsylvanian fossils (Carboniferous Period). Owing to their presumed 'basal' position in insect phylogeny, stoneflies were expected to occur at this period. However, no relative has ever been designated convincingly.ResultsIn this paper, we report specimens belonging to a new fossil insect species collected from the Tupo Formation (Pennsylvanian; China). The wing venation of Gulou carpenteri gen. et sp. nov. exhibits character states diagnostic of the order Plecoptera, but lack character states shared by unequivocal representatives of the order. Derived from this identification, the delimitation of the fossil species is ascertained based on comparison of several extant stonefly species. This comparative analysis allowed a trait present in G. carpenteri gen. et sp. nov., but rarely occurring in extant species, to be documented and highlighted as atavistic. Affinities of taxa formerly proposed as putative stem-stoneflies are reconsidered in the light of the new discovery.ConclusionsGulou carpenteri gen. et sp. nov. is considered the only genuine Plecoptera reported from the Pennsylvanian. Continuing efforts on the systematics of Pennsylvanian winged insects indicate a fauna more diverse than previously appreciated. It suggests that insects already had a long, yet undocumented, history by this time.

No abstract

No abstract

The Ephemeroptera, Plecoptera and Trichoptera (EPT; mayfly, stonefly and caddisfly, respectively) faunas of the southern Appalachian Mountains are rich in species, including many endemic species. The species richness is a result of unique geological, climatological, and hydrological features of the region. Humans have impacted, and are impacting, the stream faunas in several significant ways, primarily through air pollution (with acid precipitation), introduction of exotic forest pests, impoundments (ponds and reservoirs), sedimentation (from road building, development, deforestation, farming), toxic substances (industrial effluent, agricultural and golf course insecticides), and organic enrichment (agricultural and golf course fertilizers, trout farm effluent). Nineteen species of Bphemeroptera, 17 species of Plecoptera and 38 species of Trichoptera are identified as examples that are probably rare and vulnerable to extirpation in the southern Appalachian Mountains. The task of saving the streams and their biotas from further degradation will require thoughtful public discourse and thorough baseline and long‐term research efforts.

Perlesta placida (Hagen), long regarded as a widespread variable species, is a complex of at least 12 species which differ in pigmentation, egg morphology and male and female genital structures. Species removed from the synonymy of P. placida (= Chloroperla virginica Banks, 1898; = P. virginica immaculata Klapálek, 1921) include P. cinctipes (Banks, 1905), P. decipiens (Walsh, 1862) (= Perla brunnipennis Walsh, 1862, syn. n.; = Isoperla texana Banks, 1914, syn. n.; = P. costalis Klapálek, 1921, syn. n.) and P. nitida Banks, 1948. New species described include P. adena, P. baumanni, P. bolukta, P. browni, P. lagoi, P. nelsoni and P. shubuta. Lectotypes are designated for most older species, including P. frisoni Banks, 1948, which is also valid, and all are redescribed from types.