Size, shape, and direction matters: Matching secondary genital structures in male and female mites using multiple microscopy techniques and 3D modeling.

Studies of female genital structures have generally lagged behind comparable studies of male genitalia, in part because of an assumption of a lower level of variability, but also because internal genitalia are much more difficult to study. Using multiple microscopy techniques, including video stereomicroscopy, fluorescence microscopy, low-temperature scanning electron microscopy (LT-SEM), and confocal laser scanning microscopy (CLSM) we examined whether the complex sperm transfer structures in males of Megalolaelaps colossus (Acari: Mesostigmata) are matched by similarly complex internal structures in the female. While both LT-SEM and CLSM are well suited for obtaining high-quality surface images, CLSM also proved to be a valuable technique for observing internal anatomical structures. The long and coiled sperm transfer organ on the chelicera of the males (spermatodactyl) largely matches an equally complex, but internal, spiral structure in the females in shape, size, and direction. This result strongly suggests some form of genital coevolution. A hypothesis of sexual conflict appears to provide the best fit for all available data (morphology and life history).

Review of the mite genus Krantzolaspina Datta & Bhattacharjee (Mesostigmata, Parholaspididae) with re-description of K. angustatus comb. nov. (Ishikawa) from Indonesia.

Herein, we update the diagnosis and description of the genus Krantzolaspina Datta & Bhattacharjee and provide a list of the three valid species including new combinations and synonyms, as follows: 1) Krantzolaspina angustatus (Ishikawa, 1987) comb. nov. (= Indutolaelaps jiroftensisHajizadeh et al., 2017syn. nov.), 2) K. rebatii Datta & Bhattacharjee, 1989 and 3) K. solimani (Metwali, 1983) comb. nov. Finally, we re-describe K. angustatus (Ishikawa, 1987) comb. nov. based on the holotype from Japan, voucher specimens from Iran and additional females that we found in soil samples from oil palm plantations in Sumatra, Indonesia.

The biology of Megalolaelaps colossus (Acari: Dermanyssina).

Aspects of life history and host interactions of Megalolaelaps colossus were studied in a laboratory environment. These mites appear to require a host for survival, but hosts do not survive very long in a laboratory setting, leading to a modified rearing protocol relying on regular host replacement. Specific data on phenology and incidence are reported. Direct observations on feeding, mating, transmission, and interaction with other mites could not be obtained, but indirect observations allow some hypotheses in each of these areas.

Review of the mite genus Ololaelaps (Acari, Laelapidae) and redescription of O.formidabilis Berlese.

A species of laelapid mite, Ololaelapsformidabilis, is redescribed based on male and female adults from soil in Sumatra, Indonesia. This species is distinguished from other Ololaelaps species by its metapodal platelet narrowly fused with the parapodal plate and by its hologastric shield having two inverted-V-like ridges. The genus is redescribed based on a review of the literature and examination of specimens of some species. Valid species of Ololaelaps are listed and accompanied by notes on morphological characters to assist future revision of the genus.