Mesozoic Trichoptera with reduced venation

• Published in: Zoosymposia
• Main Authors: SUKATSHEVA, IRINA D., VASSILENKO, DMITRY V.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Zoosymposia 2016
• Subjects: caddisflies; Jurassic–Cretaceous boundary; Dysoneuridae; Baissoferidae; Taymyrelectronidae; Taymyr; Taymyr Peninsula
• Online Access: http://www.mapress.com/j/zs/article/view/zoosymposia.10.1.37; https://doi.org/10.11646/zoosymposia.10.1.37

The reduction of fore-wing venation by Mesozoic Trichoptera presumably occurred in two directions. The first, traditional direction was related to the decrease in size of their bodies, and it has been recorded for Trichoptera found in Cretaceous fossil resins. These insects are very small, they have a strongly reduced venation, which is more typical for Cenozoic or recent caddisflies than for the Cretaceous ones. Botosaneanu & Wichard (1983) described the family Taymyrelectronidae from Cretaceous resins from the Taymyr Peninsula, whose representatives had a common area free of any veins in their forewings other than DC, MC, and TC cells. The second direction is typical for primitive Trichoptera and does not concern the size of their bodies. Starting with the beginning of the Mesozoic, the Triassic and the Lower Jurassic, certain changes in the caddisflies’ morphology were noted. Thus, the reduction of veins occurred by their merging, desclerotization, disappearance, and formation of strange large bullas on R. The reduction occurred by the merging of veins, or their desclerotization or disappearance (e.g., loss of forks F1 and F4 in Dysoneuridae Sukatsheva 1968 and Baissoferidae Sukatsheva 1968). Among recent caddisflies, the Kokiriidae McFarlane 1964 are close to the Mesozoic ones because they do not have forks F1 and F4 in their forewings.