Diptacus rubuscolum Trinidad, Duarte and Navia (Eriophyoidea: Diptilomiopidae) on blackberry (Rubus ulmifolius Schott) in Mexico: occurrence, complementary description, and biology

Blackberry (Rubus ulmifolius Scott) is an economically important crop in Mexico. Eriophyoidea mites are among the most important arthropod pests affecting production of this crop worldwide. Despite this, reports on species diversity of Eriophyoidea on blackberry in Mexico are scarce. We sampled six orchards from two municipalities in the state of Michoacan, the most important region for blackberry production. Sampling was carried out monthly between May and November 2018. Only one species of eriophyoid mite was found, Diptacus rubuscolum Trinidad, Duarte and Navia. We conducted a detailed morphological study of this mite and a complementary description is presented. In addition, we obtained partial sequences of the mitochondrial cytochrome oxidase subunit I (mt COI), the 18S and 28S of the rRNA. The duration of each developmental stage was determined under controlled conditions (25 °C, 60% RH and 12:12 light regime). We confirmed the identity of D. rubuscolum by comparing partial sequences of the D2 region within the 28S rRNA from our samples and sequences retrieved from GenBank. Overall, morphological characteristics were in line with the type specimens. However, some differences on body shape and empodium structure were pointed out. The developmental stages of D. rubuscolum were egg, larva, nymphochrysalis, nymph, imagochrysalis and adult, with a mean duration of 75 (±10), 56 (±9), 21 (±7), 41 (±8), 19 (±6) and 114 (±12) hours respectively. The information produced provides insight and knowledge on the occurrence of this species on blackberry in Mexico as well as on original biological aspects.