Ontogenetic development of chaetotaxy in Tenuipalpidae: a survey with special reference to sexual dimorphism

Abstract

In this paper, we provide a comparative survey of ontogenetic development of chaetotaxy in the family Tenuipalpidae, with the aim to compare patterns among species/genera and to discover some general trends. We also want to find gaps within published literature and provide suggestions for future studies. Although we focused on the ontogeny of setal developments, we also reviewed sexual dimorphism in chaetotaxy in the family Tenuipalpidae.

A new flat mite of the genus Brevipalpus Donnadieu (Trombidiformes: Tenuipalpidae) from Brazil, with complete ontogenetic pattern of setal additions

“…Similarly, the addition of l' is delayed to the adult in Raoiella species, where l' is added to femora I–II or femur I only in the adult stage. This is in contrast to the more common pattern within the family where seta l' is added to femora I–II in the deutonymph stage, which is observed in several Tenuipalpus species as well as Ultratenuipalpus , Acaricis , Prolixus and Lisaepalpus (Welbourn et al 2017; Gu & Zhang 2020; Castro et al 2023b).…”

“…Setae d and lʺ are added to genua I-II in the deutonymph, while seta l′ is present on genu III in the larva and added to genu IV in the protonymph. The expression of seta l′ on genu III in the larva follows a common pattern also seen in other genera such as Acaricis, Cenopalpus, Meyeraepalpus, Pentamerismus, Raoiella and some Tenuipalpus species (Beard et al 2014(Beard et al , 2018Welbourn et al 2017;Gu & Zhang 2020;Negm et al 2020); whereas the presence of setae l′ on genu IV is uncommon in the family. Other species of Tenuipalpus add seta l′ on genu III in the deutonymph.…”

“…Ontogeny. This is the first study of the complete pattern of setal additions during ontogenetic development from larva to adult female in a Brevipalpus species (Gu & Zhang 2020); however, the adult male remains unknown. The additions to the coxal setae match the standard pattern for the superfamily Tetranychoidea (Lindquist 1985).…”

“…Coxal setae 1c , 2c and 3b are added in the protonymph and 2b and 4b are added in the deutonymph. Setae l' are added on trochanters III in the protonymph, which is a common pattern for the family (Welbourn et al 2017; Gu & Zhang 2020); however, the pattern of adding seta v' to the trochanters on B. canastra sp. nov. deviates from the standard.…”

“…nov. is consistent with that of B. incognitus (Navia et al 2013). Brevipalpus is unique within the family Tenuipalpidae as the only genus whose species add a second solenidion on the tarsus II in the female (Gu & Zhang 2020). The presence or absence of the paraxial solenidion ω' is a traditional character used to separate species groups within the genus (Meyer 1979; Baker & Tuttle 1987).…”