Acta Palaeontologica Polonica

A new phylloblattid dictyopteran—first fossil insect from the Arroyo Totoral Formation (Cisuralian, Permian) of La Rioja Province, Argentina

María B. Lara and Bárbara Cariglino

Acta Palaeontologica Polonica 71 (1), 2026: 19-28 doi:10.4202/app.01254.2025

The first fossil insect from the Cisuralian (Lower Permian) Arroyo Totoral Formation, south of Sierra de los Llanos, Paganzo Basin, southeastern La Rioja Province, Argentina is reported. A new species of Phyloblattidae (Dictyoptera), Anthracoblattina macucai sp. nov., is described from an almost complete forewing and based on its general venation scheme (e.g., distinct narrowing of the strip-like costal field near wing base, widened areas between the main veins, Sc pectinated, R and M slightly sigmoidal, twigs provide fan-like covering of the wing apex, the first forks of both R and M located between the first third and the half of the wing length, CuA straight, ends at the transition of the wing tip into the posterior wing border, CuP fluently curved, broad interspace between CuP and AA, cross-venation anastomosing- striate to reticulate). Additionally, we discuss the taxonomic position of A. macucai sp. nov. in relation to other phyloblattid species described from Carboniferous–Permian South American outcrops. Finally, we analyze this new fossil “cockroachoids” within its paleofloristic context and depositional environment. A. macucai sp. nov. represents the first known Permian insect found for both the La Rioja Province and the Arroyo Totoral Formation, pointing the unit as promising for the search of fossil insects in Argentina.

Key words: Dictyoptera, Phyloblattidae, Arroyo Totoral Formation, Cisuralian, Permian, Argentina.

María B. Lara [maria.belen.lara@uda.cl; lara.maria.belen@live.com.ar; ORCID: https://orcid.org/0000-0003-1621- 5594], Departamento de Química y Biología, Facultad de Ciencias Naturales, Universidad de Atacama, Av. Copayapu 485, Copiapó, Chile; Centro de Ecología Aplicada del Litoral (CECOAL-CONICET-UNNE), Ruta Provincial 5, km 2.5, 3400, Corrientes, Argentina. Bárbara Cariglino [barichi10@gmail.com; ORCID: https://orcid.org/0000-0002-4346-3502], Museo Argentino de Ciencias Naturales “Bernardino Rivadavia” (MACN), Av. Ángel Gallardo 470, C1405DJR, Ciudad de Buenos Aires, Buenos Aires, Argentina.


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