title: Ultrastructural and functional adaptations of the female reproductive system in the family Heterozerconidae (Acari, Anactinotrichida, Gamasida, Heterozerconina) and implications for the systematic position of the group.
abstract: Heterozerconidae is a poorly known, early derived mite family belonging to Heterozerconina (Monogynaspida, Gamasida (= Mesostigmata)). The systematic position of the family is still controversial and little is known about the biology and anatomy of the taxon. In this paper, the gross anatomy, ultrastructure and functional morphology of the female reproductive system are described comparing genera from different geographic areas. The occurence of podospermy (i.e. the use of a sperm transfer process carried by the fixed digit of the male chelicerae to inseminate females through secondary insemination pores instead of through the oviporus) as insemination mode in this family was documented. Nevertheless, morphological and functional evidence in the reproductive system of the females supports the idea that, in the same family, more than one insemination mode is present: some genera are plesiomorphically tocospemic (i.e. insemination through the oviporus) while others switched to podospermy. Such discovery is of fundamental importance for the determination of the relationship between the family Heterozerconidae and the family Discozerconidae, both belonging tentatively to Heterozerconina and for the phylogenetic position of the Heterozerconina among Gamasida.
authors.affiliation: Department of the Sciences of Agriculture, Food and Environment, University of Foggia, 71100, Foggia, Italy. Electronic address: antonella.dipalma@unifg.it.
authors.forename: A
authors.initials: A
authors.lastname: Di Palma
authors.affiliation: Escola Superior de Agricultura Luiz de Queiroz (ESALQ), Universidade de São Paulo (USP), 13418900, Piracicaba, SP, Brazil.
authors.forename: G J
authors.initials: GJ
authors.lastname: de Moraes
authors.affiliation: Entomology Department, Washington State University, Mount Vernon Northwestern WA Research & Extension Center, Mount Vernon, WA, 98273-4768, United States.
authors.forename: B S
authors.initials: BS
authors.lastname: Gerdeman
authors.affiliation: Ottenbohlstrasse 12, 88690, Mühlhofen, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Huber
authors.affiliation: Escola Superior de Agricultura Luiz de Queiroz (ESALQ), Universidade de São Paulo (USP), 13418900, Piracicaba, SP, Brazil.
authors.forename: E W
authors.initials: EW
authors.lastname: Kitajima
authors.affiliation: Allgemeine und Systematische Zoologie, Zoologisches Institut und Museum, Universität Greifswald, 17489, Greifswald, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Alberti
mesh_terms: D000818:Animals; D005260:Female; D005836:Genitalia, Female / Q000033:anatomy & histology / Q000502:physiology / Q000648:ultrastructure; D007314:Insemination; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D008925:Mites / Q000033:anatomy & histology* / Q000145:classification / Q000502:physiology* / Q000648:ultrastructure; D010802:Phylogeny; D012098:Reproduction
keywords: Insemination mode; Plesiomorphic characters; Podospermy; Secondary insemination system; Spermatophores; Tocospermy; Vesicle