Legrandella is a genus of synziphosurine,[1] a paraphyletic group of fossil chelicerate arthropods.[2][3] Legrandella was regarded as part of the clade Prosomapoda.[2][4][5][6][3][7] Fossils of the single and type species, L. lombardii, have been discovered in deposits of the Devonian period in Cochabamba, Bolivia.[7][2]
The prosoma of Legrandella covered by a vaulted carapace with anterior projection, blunt genal cornua (posterolateral corners), humped cardiac lobe and pairs of radiated grooves.[1] Alongside Pseudoniscus roosevelti, Legrandella lombardii is one of the few synziphosurine species that confirmed to have lateral compound eyes.[8] The eyes are slit-like, located just below the ophthalmic ridges on each side of the carapace.[1] The opisthosoma is externally 11-segmented, subdivided into a 8-segmented preabdomen and 3-segmented postabdomen.[1] Tergite of the 1st preabdomimal segment is a reduced microtergite while the remaining 7 tergite possess axial nodes and spine-like tergopleurae (lateral extension).[1] each of the postabdominal segment is cylindrical and bore reduced tergopleurae.[1] The telson is triangular in cross section, but the distal region is yet to be discovered.[1]