Taxonomy of the Family Teneriffiidae (Acari: Prostigmata: Anystoidea): Generic Synonymies with the Key to World Species of the Family.

The family Teneriffiidae Thor has an equivocal and patchy generic history due to a lack of proper diagnostic character/s, causing the addition of an over-sufficient number of genera (i.e., nine) for the 28 described species. The present study aimed to resolve those taxonomic uncertainties related to generic divisions and species assignments by thoroughly reviewing all the published literature of the family, identifying key diagnostic character/s for generic divisions while debating on previously used morphological features. In the present research, only two genera, Teneriffia Thor and Parateneriffia Thor, are considered valid genera in the family Teneriffiidae, based on the absence and presence of palpgenu oncophysis, respectively. The previously used other generic diagnostic characters such as coxal setal formula, pectination strength of leg claws, absence or presence of genital papillae, genital discs, and pedal solenidion have been argued for their inconsistencies. A total of four species were synonymized with the closely related species, while additional notes for six poorly described species are given. Moreover, the key to the genera and species of the family Teneriffiidae is provided.

Does the sampling of date palm fruits help in early detection of date palm mite, Oligonychus afrasiaticus (Acari: Tetranychidae)?

Early pest detection in an agroecosystem is desired for efficient pest management. A proper sampling plan is thus required with adequate sampling units and a small sample size. The date palm mite, Oligonychus afrasiaticus, is a severe pest of date fruits and its early detection is most needed. The present research aimed to identify whether a certain bunch direction or strand position of date fruit bunches could help in the early detection of date palm mite. The research was conducted in two climatic regions of Saudi Arabia, on six date palm cultivars and during four fruiting seasons. The date palm mite population dynamics data were collected from four bunch directions and three strand positions. For early pest detection, the population estimation started from the first appearance of the mite on the fruit bunches in each season, continuing till the first 3 weeks. The results depicted a clumped distribution of date palm mite in all bunch directions and strand positions. There was no significant difference in the mean date palm mite population, neither among three-strand positions nor among the four bunch directions. The mean population over the weeks showed that date palm mite almost equally infested the fruit bunches from all four directions and increased with non-significant differences. It is suggested that the plant parts basally adjacent to fruit bunches should be focused on the early detection of date palm mite.

New subgenera and a new species of the genus Raphignathus Dugès (Prostigmata, Raphignathidae), with taxonomic notes on the genus Neoraphignathus Smiley & Moser.

Four new subgenera in the genus Raphignathus Dugès are hereby proposed: Raphignathus (Raphignathus), subgen. nov., Raphignathus (Monoraphignathus), subgen. nov., Raphignathus (Diraphignathus), subgen. nov., and Raphignathus (Triraphignathus), subgen. nov. These subgenera are diagnosed by the number of setae on the interscutal membrane of females. A new species, R. (D.) neohecmatanaensissp. nov., is described and illustrated based on females collected from Ziziphusspina-christi Mill. (Rhamnaceae). The taxonomic status of the monotypic genus Neoraphignathus Smiley & Moser and three species (R.evidus, R.hsiufui, and R.johnstoni) are discussed. A key to world species of the family Raphignathidae is given.

New Genus and New Subgenera of Camerobiid Mites (Acari: Prostigmata: Camerobiidae) with a Key to World Species of the Genus.

A new genus, Monobius Alatawi and Kamran, is hereby proposed for the two already described species, viz; M. electrus (Zmudzinski) and M. meyerae (Bolland). In addition, the monospecific genus Tillandsobius Bolland is synonymized with the genus Tycherobius Bolland due to variations in the setae number of tibiae I-IV. Further, the genus Neophyllobius Berlese is categorized in two new subgeneric divisions as Neophyllobius Berlese and Monophyllobius Mirza. The number and position of the midventral setae on tarsi I-IV are considered as strong diagnostic generic and subgeneric diagnostic characters. The present study also includes the key to all known species of the genus Neophyllobius. The morphological characters of ten poorly described Neophyllobius species were studied in detail through published literature. The ambiguities in the ventral idiosoma setal notation are highlighted and discussed. It is concluded that two intercoxal setae 3a-4a are always present on small platelets, paired aggenital setae (ag) are present anteriorly and paired genital setae (g) present posteriorly on genital shield. In addition, five records of new species for Saudi Arabia are reported along with re-descriptions of three species.

Phenology and abundance of date palm mite Oligonychus afrasiaticus (McGregor) (Acari: Tetranychidae) in Riyadh, Saudi Arabia.

In the present study, we evaluated the effect of management practices, fruit season, host habitats (young and old fronds, date fruits and grasses), and temperature on the phenology and abundance of the date palm mite (DPM). The study was conducted in two date palm orchards (two plots each): a managed and an unmanaged plot. The phenology of DPM was assessed based on adult cumulative mite days (ACMDs), while mean mite density was used to assess the mite abundance on different host habitats. The ACMDs and mean mite density were significantly different between managed and unmanaged plots on different host habitats in both fruiting and off-seasons. The date fruits had highest ACMDs during fruiting season. While young fronds had significantly higher ACMDs than on old fronds an grasses during both seasons in both plots.. The temperature and season type significantly affected the mean density of DPM eggs and adults. There was a significant effect of host habitats mean density of DPM eggs and immatures. Based on the adult phenology and abundance of DPM, the mite overwinters in young fronds and aerial offshoots of infested date palm trees. These overwintering DPM caused the seasonal date fruit infestation, each year. Additionally, different phytophagous and predatory mites, which co-occur with DPM, and were found on different host habitats affected the phenology and abundance of DPM. Moreover, the change in DPM body color was related to the host habitat that they fed in. Exceptionally, the brown color of females collected during the winter season could be due to physiological changes due to low temperature. In DPM males collected from different host habitats throughout the study, some morphological variations in the width of the knob, height of the hook, and the angle between the knob axis and dorsal margin of the shaft were also recorded. The results of this study suggest that young fronds and grasses are the suitable sites for DPM survival and overwintering. Hence, the management practices, early in the fruit season and/or during off fruit winter months, should be directed towards these habitats. These could provide efficient reduction in seasonal infestation of DPM.

Molecular and phenotypic variations in Eutetranychus orientalis (Klein) populations from Saudi Arabia.

The oriental red spider mite, Eutetranychus orientalis (Klein) is a major pest of citrus in many countries including Saudi Arabia (SA). The morphological variations among the different populations of E. orientalis were reported. In the present study, phenotypic variations based on 40 different morphological characteristics were evaluated in 10 E. orientalis populations collected from different hosts and regions of SA. Further, ITS2-rDNA sequences were used to confirm the identity of these phenotypically varying populations. Phenotypic variations in all populations were found in the shape and length of dorsal setae, striation pattern between setae d1 and e1, and leg chaetotaxy. The rDNA sequence analysis of these morphologically varying populations resulted in 10 different ITS2 Saudi haplotypes. The phenotypic and genetic variations were more related to the host plants rather than their geographic distribution. The E. orientalis population collected from Phoenix dactylifera was phenotypically distinct and genetically divergent. The populations collected from citrus species were also more phenotypically and genetically related to each other than to populations collected from non-citrus host plants. The haplotypes recovered from Ziziphus sp., Morus sp., and Azadirecta indica from different regions were grouped in the same sub-clade. Further, the ITS2 haplotypes of Saudi E. orientalis recovered from Citrus reticulata from Riyadh and Al Ula were 100% identical to the ITS2 haplotypes recovered from Citrus sp. from Israel. It is concluded that phenotypic variations exist among different populations of E. orientalis inhabiting different host plants. This species should be identified carefully by considering phenotypic intraspecific variations.

Webbing life type and behavioral response of the date palm mite, Oligonychus afrasiaticus, to webbing residues on leaves and fruits of date palm.

The present study examined the webbing life type and behavioral response of date palm mite (DPM) Oligonychus afrasiaticus (McGregor) toward its webbing residues, in presence or absence of immature individuals, on leaves and fruits of date palm. DPM exhibited a complicated web life type on both the leaves and fruits of date palm, which is characterized by the following features: complicated irregular web structure; webbing density on the leaves is medium and on the fruits extremely high; eggs are always laid on the threads of web without web cover; fecal pellets are deposited on the substrate surface (both leaf and fruit); quiescent stages are on the silken web threads; and the preferred site for feeding and walking is under the web. Behavioral observation of DPM females revealed that the midrib of leaves and the base of fruits of date palm were the preferred sites for feeding and web construction. The number and development stage of DPM affected the behavioral response of females on date palm leaves but not on the fruits. DPM spent most time feeding under the web on both the leaves and fruits of date palm.

Response of the predatory mite Cydnoseius negevi (Acari: Phytoseiidae) to webbing of the date palm mite, Oligonychus afrasiaticus (Acari: Tetranychidae), on date palm fruits and leaves.

The behavioral response of a generalist phytoseiid predator, Cydnoseius negevi (Swirskii & Amitai) (Acari: Phytoseiidae) to the complicated webbing of the date palm mite (DPM) Oligonychus afrasiaticus (McGregor) (Acari: Tetranychidae) was evaluated for the first time on date palm leaves and fruits, both in the laboratory and on field-collected samples. Cydnoseius negevi used its first pair of legs in a swimming-like to-and-fro movement to penetrate the complicated webbing of DPM and demonstrated three attack behaviors, i.e., patrolling (PG), web invasion (WI), and web penetration (WP), against the webbing of DPM on date fruits and leaves. The time spent by the predator on attack behaviors was significantly longer in the laboratory for treatments where either more prey females or immature stages along with females were present. The time spent by C. negevi on response behaviors such as searching, grooming, and resting increased with increased number of DPM females and with the addition of immature stages along with DPM females. Cydnoseius negevi, even though being a generalist phytoseiid predator, showed its potential towards penetrating the complex dense webs of DPM on date palm fruits and leaves. If released in suitable numbers prior to establishment of DPM colonies, C. negevi may prove to be an effective biological control agent.

Mesostigmatic mites (Acari: Mesostigmata) of Saudi Arabia (excluding Phytoseioidea), new records and a key to the known species.

This paper reports on 35 species and 33 genera belonging to 18 families of the order Mesostigmata, collected from different provinces of Saudi Arabia. Among these, eight families, 21 genera and 30 species, mostly collected from date palm agroecosystem, are new to the fauna of Saudi Arabia. Five species reported previously are also recorded in this study. The collection data and distribution of all species recorded in this study as well as those reported previously are given. A comprehensive key to the females of the mesostigmatic mites reported from Saudi Arabia, except the Phytoseioidea, is provided.

The genus Paraplonobia Wainstein and Neopetrobia Wainstein (Acari, Trombidiformes, Tetranychidae) from Saudi Arabia: new species, new records and key to the world species of Paraplonobia.

The two tetranychid genera Paraplonobia Wainstein and Neopetrobia Wainstein (Trombidiformes: Tetranychidae) are reported for the first time from Saudi Arabia. Three new species Paraplonobia (Anaplonobia) arabica Mirza & Alatawi, sp. n., Paraplonobia (Anaplonobia) haloxylonia Alatawi & Mirza, sp. n. and Paraplonobia (Anaplonobia) tabukensis Kamran & Alatawi, sp. n. are described and illustrated based on adult females, collected from Prosopis juliflora (SW.) Dc. (Fabaceae) and Haloxylon salicornicum Bunge (Amaranthaceae) from two different regions of Saudi Arabia. Neopetrobia mcgregori (Pritchard and Baker) is redescribed and illustrated based on female collected from Cynodon dactylon L. (Poaceae).The diagnostic morphological features including leg chaetotaxy of all known species of the subgenus Anaplonobia is tabulated. A key to the world species of the genus Paraplonobia is also provided.