Evolution of parasitism in mammal-associated mites of the Psoroptidia group (Acari: Astigmata)

The distribution of parasitic mites of the Psoroptidia group on mammals was analyzed. Nearly all the mammal-associated Psoroptidia belong to the paraphyletic superfamily Sarcoptoidea. Mites of the family complex Psoroptidae (Lobalgidae, Psoroptidae, and Paracoroptinae) shifted from birds to parasitism on placental mammals independently from each other. Mites of the Sarcoptidae complex, comprising all the other mammal-associated Psoroptidia, originated from the common stalk of Psoroptidia independently. They are widely represented on both marsupial and placental mammals and are primarily or secondarily absent on Monotremata.     

Evolution of parasitism in mammal-associated mites of the group Psoroptidia (Acari:Astigmata)

Host-parasite relationships of mammals and astigmatan mites (Acariformes: Astigmata) belonging to the parvorder Psoroptidia are analyzed. The absolute majority of mammal-associated psoroptidians belongs to the paraphyletic superfamily Sarcoptoidea. Mites of the family complex Psoroptidae (Lobalgidae, Psoroptidae, and Paracoroptinae) shifted from birds to placental mammals independently from each other. Mites of the family complex Sarcoptidae, including all other sarcoptoid families, derived from the common stalk of Psoroptidia independently from the Psoroptid complex. Mites of the sarcoptid complex shifted from nidicoly in mammalian nests to the permanent parasitism on these hosts. They are widely represented on both marsupial and placental mammals and are absent on Monotremata.     

Origin and Evolution of Feather Mites (Astigmata)

Feather mites are highly specialized plumage and skin ectoparasites that are variously adapted for inhabiting certain microhabitats on a bird's body. Different feather mite taxa of higher (familial) rank adapted to the same microhabitats display similar main morphological adaptations even if they are rather distantly related to one another. Hypotheses on the evolution of general adaptations in morphology of feather mites during colonization and establishment in different microhabitats are presented. According to recent data, feather mites are a paraphyletic group consisting of three superfamilies: Analgoidea, Pterolichoidea and Freyanoidea. We present our view on the general feather mite phylogeny course at the familial rank for the Analgoidea by means of cladistic analysis. Co-speciation of parasites with their hosts is postulated as a main factor driving feather mite evolution. Examples are given of non-coevolutionary events, for example recolonization from one host species onto another, extinction and multiple speciation.     

Molecular identification and phylogenetic analysis of economically important acaroid mites (Acari: Astigmata: Acaroidea) in Korea

Molecular diagnosis is highly valuable for the species identification of microscopic mites. Here, we collected some economically important mites of the superfamily Acaroidea from various stored products in Korea. Those nucleotide sequences of ribosomal second internal transcribed spacer (ITS2) and the mitochondrial cytochrome oxidase subunit I (COI) regions were determined by PCR using universial primers. In nucleotide sequence comparison at GenBank database, seven species including Rhizoglyphus robini, R. echinopus, Sancassania sp. Acarus siro, Tyrophagus putrescentiae, T. similis in Acaridae and Suidasia medanensis in Suidasiidae were identified. Particularly, COI sequences of R. robini, R. echinopus, Sancassania sp. and T. similis were firstly determined. Our results suggest that the phylogenetic relationships inferred from the ITS2 region, rather than COI region, were similar to those derived based on their morphological classification. Our study provides molecular information for the identification and phylogenetic relationship of acaroid mites in Korea.     

Origin and higher-level relationships of psoroptidian mites (Acari: Astigmata: Psoroptidia): evidence from three nuclear genes

Phylogenic relationships of the Psoroptidia, a group of primarily parasitic mites of vertebrates, were investigated based on sequences from three nuclear genes (4.2 kb aligned) sampled from 126 taxa. Several morphological classification schemes and a recent molecular analysis, suggesting that the group may not be monophyletic were statistically rejected by newly generated molecular data, and the results are robust under a range of analytical and partition strategies. Six families Psoroptidae, Lobalgidae (mammalian parasites), Pyroglyphidae (house dust mites and parasites inside feather calamus), Turbinoptidae (upper respiratory track parasites of birds), Psoroptoididae (downy feather mites), and Epidermoptidae (skin parasites of birds) form a well-supported monophyletic group (the epidermoptid-psoroptid complex). These relationships, recovered by combined and separate analyses of all gene partitions, were previously suspected based on some morphological evidence, but evidence has been dismissed as resulting from convergence based on similar parasitic ecologies. The existence of the epidermoptid-psoroptid complex and the statistical rejection of Sarcoptoidea (the morphology-based group joining all mammal-associated mites) indicate that current classification criteria, influenced as they are by host preferences, need to be reassessed for non-pterolichoid superfamilies. However, two of our findings remain sensitive to analytical methods and assumptions: (i) the families Heterocoptidae and Hypoderatidae as the first and second closest outgroups of Psoroptidia, respectively, and (ii) the superfamily Pterolichoidea (including Freyanoidea) forming a sister clade to the remaining psoroptidian superfamilies. Our findings suggest that (i) house dust mites (Pyroglyphidae: Dermatophagoidinae) originated from a parasitic ancestor within the core of Psoroptidia, violating a basic principle of evolution that it is virtually impossible for a permanent parasite to become free-living, and (ii) there were at least two shifts from presumably avian to mammalian hosts.     

Antigenic characterization of Psoroptes spp. (Acari: Psoroptidae) mites from different hosts

Immunoblotting with defined antigens and antisera revealed extensive and nearly complete antigenic cross-reactivity between Psoroptes spp. mites from a bighorn sheep, a mule deer, a cow, and a rabbit. Antigenic differences were not detected between mites from the sympatric bighorn sheep and mule deer. However, minor antigenic differences between mites from the cow and rabbit suggested that these mites were distinct from each other, as well as from the mites from the bighorn sheep and mule deer. These results are consistent with earlier morphologic studies of these populations of mites and provide additional support for the hypothesis that putative populations and/or species of Psoroptes mites may not be reproductively or ecologically isolated, particularly when their hosts are sympatric.     

Larval parasitism of spring-dwelling alpine water mites (Hydrachnidia,Acari): a study with particular reference to chironomid hosts

During faunistic investigations on spring habitats in the alpine National Park Berchtesgaden (Bavaria, Germany), water mites were found to be the group with the highest share of species strongly adapted to springs. At four sample sites at two spring complexes, insect emergence was screened for parasitism by larval water mites. A total of at least 36 host species were recorded as being parasitized by 19 water mite species. As in many other habitats, the most important host taxon was shown to be the nematoceran family Chironomidae, both in the number of species and individuals parasitized. Likewise, the number of water mite species attached to chironomids was high. Further host species were found among the Plecoptera, Trichoptera, Coleoptera, Limoniidae and Empididae (Diptera). These taxa were only parasitized by a single water mite species in each case. For 13 mite species, new hosts were recorded for the first time. For another six species, the known host spectrum could be confirmed and/or supplemented. The parasitological data presented (e.g., prevalences, selected attachment sites on the host, larval phenology, intensity of parasitism) provide, in most cases, basic information concerning previously unknown parasite–host associations. At this time, the reason for the strong crenobiosis in water mites cannot be explained by their parasitism.     

Gonads and gametogenesis in astigmatic mites (Acariformes: Astigmata)

Astigmatans are a large group of mites living in nearly every environment and exhibiting very diverse reproductive strategies. In spite of an uniform anatomical organization of their reproductive systems, gametogenesis in each sex is highly variable, leading to gamete formation showing many peculiar features and emphasizing the distinct position of Astigmata. This review summarizes the contemporary knowledge on the structure of ovaries and testes in astigmatic mites, the peculiarities of oogenesis and spermatogenesis, as well as provides new data on several species not studied previously. New questions are discussed and approaches for future studies are proposed.     

Hide protease in stored product mites (Astigmata:acaridae)

• 1.1. Hide protease activity was detected in 6 species of stored product mites; Acarus siro Linnaeus, Glycyphagus destructor (Schrank), Glycyphagus domesticus (De Geer), Rhizoglyphus callae (Oudemans), Rhizoglyphus robini Claparede and Tyrophagus longior (Gervais).
• 2.2. Significant differences in specific activity were found between, but not within, species.
• 3.3. A. siro L. and Glycyphagus spp. show relatively high activity, Rhizoglyphus spp. and T. longior (Gervais) relatively low activity.
• 4.4. Possible explanations for these results are discussed.

     

Gonads in Histiostoma mites (Acariformes: Astigmata): Structure and development

The development of male and female gonads in arrhenotokous and thelytokous species of Histiostoma was studied using transmission electron microscopy (TEM). All instars were examined: larvae, protonymphs, facultative heteromorphic deutonymphs (=hypopi), tritonymphs, and adults. In testis primordium, spermatogonia surrounding a testicular central cell (TCC) with a gradually enlarging, branched nucleus are present already at the larval stage. Spermatogonia and the TCC are connected via narrow, tubular intercellular bridges revealing that the TCC is a germline cell. Spermatocytes appear at the protonymphal stage. At the heteromorphic deutonymph stage, the testis primordium is similar to that of the protonymph, but in the tritonymph it is much larger and composed as in the adult: spermatids as well as sperm cells are present. The latter are congregated ventrally in the testis at the entrance of the deferent duct.In the larval ovary, an eccentrically located ovarian nutritive cell (ONC) is surrounded by oogonia which are connected with the ONC via tubular intercellular bridges. In later stages, the ovary grows and oocytes appear in the protonymph. Meiotic synaptonemal complexes in oocytes occur from the tritonymph stage. At about the time of the final molting, tubular intercellular bridges transform into peculiar diaphragm-crossed bridges known only in Histiostoma mites. In the adult female, growing oocytes at the end of previtellogenesis lose intercellular bridges and move ventro-laterally to the ovarian periphery towards the oviduct entrance. Vitellogenesis occurs in oviducts.Germinal cells in both the testis and ovary are embedded in a few somatic stroma cells which may be well discernible already in the larval ovary; in the testis, somatic stroma cells are evident not earlier than the end of the tritonymphal stage. The ovary has a thin wall of flat somatic cells, whereas the testis is covered by a basal lamina only.The obtained results suggest that gonads in Histiostoma and other Astigmata originate from two primordial cells only.     

Mitochondria-rich cells in the astigmatic mites,Diplaegidia columbae (Buchholz) (Analgidae) and Falculifer rostratus (Buchholz) (Falculiferidae) (Acari: Astigmata)

Mitochondria are well-characterized intracellular organelles usually concentrated in locations of high energy consumption. Light microscopic and transmission electron microscopic observations of the internal anatomy of the feather mites Diplaegidia columbae and Falculifer rostratus were conducted. In the anterior half of the bodies of the mites, we found several dozen of distinctive mitochondria-rich (MR) cells filled with abundant, large mitochondria. Mitochondria are placed individually or enclosed in small groups within an elaborated lamellar system forming a mitochondria–lamellae complex (MLC). The role of the MLC as well as the MR cells is not clear at present, but their involvement in heat generation is hypothesized and briefly discussed.     

Phylogenetic relationships in the skin-inhabiting Sarcoptoidea (Acari: Astigmata)

A phylogenetic analysis of relationships is carried out among the skin-inhabiting mites presently included in the families Rhyncoptidae, Audycoptidae and Sarcoptidae. The analysis included eight taxa (five genera of follicle associates and three subfamilies of skin-burrowing sarcoptids) and 41 characters, and generated a single most parsimonious tree of length 60 with a consistency index of 0.745. The genus Caenolestocoptes (Sarcoptidae, Caenolestocoptinae) is the sister group of the assemblage of Ursicoptes, Saimirioptes, Audycoptes (all Audycoptidae) and Rhyncoptes (Rhyncoptidae). Within the latter grouping Audycoptes is the sister group of Rhyncoptes. Based on these results the Caenolestocoptinae Fain & Lukoschus, 1976 and Audycoptidae Lavoipierre, 1964 are synonymised with the Rhyncoptidae Lawrence, 1956. The Rhyncoptidae (sensu nov.) appears to be the sister group of the Sarcoptidae (sensu stricto).The distribution pattern of follicle inhabitation and skin-burrowing in the Sarcoptoidea can be explained by one adaptation to follicle inhabitation (Rhyncoptidae), another to skin-burrowing (Sarcoptidae) and possibly a third in their common ancestor from living on the hairs or on the skin to living in the skin (follicles, burrows or both).New host and locality data for various taxa in the Rhyncoptidae (sensu nov.) are provided. The larva of Audycoptes lawrencei Lavoipierre, 1964, is described and the female redescribed.     

Marine mites (Halacaroidea: Acari): a geographical and ecological survey

Halacarid mites (Acari), with almost 700 species described, inhabit marine and freshwater habitats. The majority of genera are recorded from at least two ocean basins or continents. There is no evidence of endemic genera, in either littoral faunal provinces or in deep-sea regions. Copidognathus, a genus comprising 1/4 of all species described, is found in almost all geographic regions, depths and habitats. Other genera dominate or are restricted to cold waters, to warm waters or to distinct habitats.Corresponding habitats on either side of the boreal Atlantic Ocean harbour congeneric, identical, sibling or morphologically similar species. The fauna in the western Atlantic is less diverse than that in the eastern. Amphiatlantics are restricted to certain genera. Transatlantic distribution is independent of the niche inhabited.Of the marine halacarid species recorded from the boreal western Atlantic, 41% are amphiatlantics, while only one species is recorded from both the Caribbean and the Mediterranean. The Caribbean and the Mediterranean faunas are dominated by genera in which amphiatlantics are unknown.Most of the Black Sea species of the genus Halacarellus also occur in the Baltic, North Sea or North Atlantic, whereas the Copidognathus fauna of the Black Sea is similar to that of the Mediterranean.Halacarids are thought to be an ancient taxon, with most genera probably having been present since the Mesozoic and with several species having an age of at least 50 million years. Evidence for their antiquity is found in the distributional pattern of marine and limnic genera and species, in the lack of endemic genera despite low fecundity and lack of dispersal stages, and in the fact that amphiatlantics are restricted to certain genera without relationships to the niches inhabited.     

Potential impacts on Japanese fauna of canestriniid mites (Acari: Astigmata) accidentally introduced with pet lucanid beetles from Southeast Asia

To develop a risk-assessment system for small organisms accidentally introduced with imported organisms, we investigated as a first case study parasitic canestriniid mites, which have been imported into Japan via pet lucanid beetles from Southeast Asia. We collected mites from pinned specimens of Japanese lucanids collected before 1999—when the Japanese government lifted a ban on the import of the beetles—and living mites from imported and native lucanid beetles collected after that. No foreign canestriniid was found on any of the native Japanese beetles. Because the mites collected from imported beetles were different from Japanese species, we conclude that the foreign mites have not yet established wild populations in Japan. However, because the Japanese mites migrate between hosts without host physical contact, introduced mites are assumed to be able to migrate from a foreign to Japanese host. In fact, possible contamination was observed in pet shops. We observed host switching in only one direction: Southeast Asian Canestrinia nr spectanda switched to Japanese Dorcus rectus, but Japanese Coleopterophagus berlesei never switched to Indonesian D. titanus. The foreign mites reproduced between 15°C and 25°C, suggesting that the mites could survive in mountainous sites in southern Japan and at low elevations in northern Japan. The ability of foreign parasitic canestriniids to infect and survive on Japanese hosts at temperatures characteristic of much of Japan leads us to conclude that these mites present a potential risk to Japanese endemic canestriniids as well as to native Japanese lucanids.     

Neohyadesia microtricha (Acari: Astigmata: Algophagidae): a new species from the sub-Antarctic

The sub-antarctic mite genus Neohyadesia (Acari: Astigmata) is known from two described taxa: N. signyi from Signy Island (South Orkney Islands, South Atlantic Province), and a subspecies, N. s. punctulata from Ile Kerguelen (South Indian Province). This paper describes a second species distinguishable by, in particular, cuticular microtrichae covering the dorsal surface. The new species, N. microtricha sp. nov., has a similarly disjunct sub-antarctic distribution, occurring on both Marion (SIP) and South Georgia (SAP) islands. A systematic synopsis of the sub-antarctic algophagine mites is given. Accepted: 30 June 2000     

Five new canestriniids (Acari: Astigmata) from Papua New Guinea

Five new species from Papua New Guinea representative of five genera of astigmatous acari belonging to the family Canestriniidae are described.     

Morphological evidence for the evolutionary origin of Astigmata (Acari: Acariformes)

A century ago, Antonio Berlese first discussed the close phylogenetic relationship between the large mite groups Oribatida and Astigmata. Since then, information having phylogenetic value has greatly increased and the paradigms within which we interpret it have changed. Herein I refine the general hypothesis that Astigmata originated within oribatid mites and suggest Malaconothridae as a possible sister group. Among the 14 apomorphies used to support the origin of Astigmata within oribatid mites are possession of lateral opisthosomal glands, regression of hysterosomal setal pair f1, paired prelarval denticles, partially internalized chelicerae with incomplete adaxial walls, an atelobasic rutellum, pretarsal condylophores that articulate posteriorly with the tarsus, a dorsally fused palp tibia and tarsus and transdehiscent ecdysis. A further 13 apomorphies support the origin of Astigmata at some level within Malaconothroidea. These include absence of an oblique labiogenal articulation, presence of a distal rutellar lamella, shortening of the palp tarsus, larval regression of hysterosomal seta f2, loss of the bothridial seta in all instars, and several losses and modifications of leg setae. The hypothesis brings to light evolutionary questions that were previously obscured by incorrect or inappropriate classifications. The nomenclatural problems that arise from it are best solved by considering Astigmata as a subgroup within Oribatida.     

Astigmatid mites (Acari: Sarcoptiformes) of forensic interest

This paper reviews the occurrence of mites of the infraorder Astigmata in situations involving the legal system, particularly in the area of medicocriminal entomology. Species in the families Acaridae, Lardoglyphidae and Histiostomatidae are encountered in stored food products and in vertebrate carrion, including human remains. Some of these species are incidentals, whereas others are obligate necrophages. Phoretic associations between these mites and insects allows for rapid dispersal and colonization of such patchy resources.