Observations on the chaetotaxy of the legs in the free-living Gamasina (Acari: Mesostigmata)

Abstract

Studies on the chaetotaxy of the legs of the free-living Gamasina have shown that segmental chaetotactic patterns provide valuable taxonomic criteria for the classification of the group. The application of leg chaetotaxy to the classification of the Gamasina at species, genus and family levels is discussed. A system of setal nomenclature is introduced for individual leg segments.Evans, Gwilym O. 1963. "Observations on the chaetotaxy of the legs in the free-living Gamasina (Acari: Mesostigmata)." Bulletin of the British Museum

Two new species of Gaeolaelaps (Acari: Mesostigmata: Laelapidae) from Iran, with a revised generic concept and notes on significant morphological characters in the genus

“…The notation for idiosomal setae follows that of Lindquist & Evans (1965) adapted by and Lindquist (1994), and that for leg and palp setae follows that of Evans (1963aEvans ( , 1963b. Distinction of idiosomal pore-like structures as glandular openings (gland pores or solenostomes) versus poroids (proprioceptors or stress receptors, often called 'lyrifissures') were distinguished based on previous work by Athias-Henriot (1969b, 1975 on various Mesostigmata and by Krantz & Redmond (1987) on Macrochelidae, and their notation generally follows that of Athias-Henriot (1975) for the dorsal idiosoma, and Athias-Henriot (1971) for the ventral idiosoma.…”

A new mite species of the genus Lasioseius (Acari: Gamasina: Ascidae) from central Europe

“…All measurements in micrometers (µm) used in the text and figures were taken from slide-mounted specimens with stage calibrated ocular micrometer. The anatomical nomenclature and morphological features of specimens in this paper follow the classification by Evans (1958Evans ( , 1963 suggested for the family Ascidae, later used and completed by Lindquist & Evans (1965) and Halliday et al (1998). The differential diagnosis of the species reflects the key for the genus Lasioseius given by Christian & Karg (2006).…”

“…These authors placed the genus Lasioseius in the family Podocinidae, taking into account Karg's classification of Mesostigmata (Karg 1965(Karg , 1993. While the position of the genus Lasioseius in the family (Ascidae or Podocinidae) is still disputable, the majority of acarologists prefer the more complex family-level classification suggested by Halliday et al (1998) based on wider set of characteristics supported by the information on leg chaetotaxy (Evans 1963). Despite of different understanding of classification of family-level characteristics, the morphological features and the classification of the genus Lasioseius is clear for most of the acarologists.…”

Two new taxa of Parholaspidae Evans, 1956 (Acari, Mesostigmata) from Tenerife (Canary Islands)

“…Morphological observations, measurements (given in micrometers and made with stage-calibrated eyepiece micrometers) and illustrations were made using compound microscopes equipped with phase-contrast optical systems. Idiosomal setal notation follows Lindquist & Evans (1965), with modifications for the caudal region as given by Lindquist (1994) and Lindquist & Moraza (1999); leg chaetotaxy follows Evans (1963). Idiosomal notation of glands and lyrifissures follows Johnston & Moraza (1991).…”