Horizontal transmission maintains host specificity and codiversification of symbionts in a brood parasitic host.

In host-symbiont systems, interspecific transmissions create opportunities for host switches, potentially leading to cophylogenetic incongruence. In contrast, conspecific transmissions often result in high host specificity and congruent cophylogenies. In most bird-feather mite systems, conspecific transmission is considered dominant, while interspecific transmission is supposedly rare. However, while mites typically maintain high host specificity, incongruent cophylogenies are common. To explain this conundrum, we quantify the magnitude of conspecific vs. interspecific transmission in the brood parasitic shiny cowbird (Molothrus bonariensis). M. bonariensis lacks parental care, allowing the assessment of the role of horizontal transmission alone in maintaining host specificity. We found that despite frequent interspecific interactions via foster parental care, mite species dispersing via conspecific horizontal contacts are three times more likely to colonize M. bonariensis than mites transmitted vertically via foster parents. The results highlight the previously underappreciated rate of transmission via horizontal contacts in maintaining host specificity on a microevolutionary scale. On a macroevolutionary scale, however, host switches were estimated to have occurred as frequently as codivergences. This suggests that macroevolutionary patterns resulting from rare events cannot be easily generalized from short-term evolutionary trends.

Diversity and structure of feather mite communities on seabirds from the north-east Atlantic and Mediterranean Sea.

The richness and structure of symbiont assemblages are shaped by many factors acting at different spatial and temporal scales. Among them, host phylogeny and geographic distance play essential roles. To explore drivers of richness and structure of symbiont assemblages, feather mites and seabirds are an attractive model due to their peculiar traits. Feather mites are permanent ectosymbionts and considered highly host-specific with limited dispersal abilities. Seabirds harbour species-rich feather mite communities and their colonial breeding provides opportunities for symbionts to exploit several host species. To unravel the richness and test the influence of host phylogeny and geographic distance on mite communities, we collected feather mites from 11 seabird species breeding across the Atlantic Ocean and Mediterranean Sea. Using morphological criteria, we identified 33 mite species, of which 17 were new or recently described species. Based on community similarity analyses, mite communities were clearly structured by host genera, while the effect of geography within host genera or species was weak and sometimes negligible. We found a weak but significant effect of geographic distance on similarity patterns in mite communities for Cory's shearwaters Calonectris borealis. Feather mite specificity mainly occurred at the host-genus rather than at host-species level, suggesting that previously inferred host species-specificity may have resulted from poorly sampling closely related host species. Overall, our results show that host phylogeny plays a greater role than geography in determining the composition and structure of mite assemblages and pinpoints the importance of sampling mites from closely-related host species before describing mite specificity patterns.

New feather mites of the genus Neodectes (Acariformes: Proctophyllodidae) from honeyeaters (Passeriformes: Meliphagidae) in Australia.

Five new species of the genus Neodectes Park and Atyeo, 1971 (Proctophyllodidae: Pterodectinae) are described from honeyeaters (Passeriformes: Meliphagidae) in Australia: Neodectes cissomelae sp. n. from Cissomela pectoralis (Gould) (type host) and Melithreptus gularis laetior Gould; N. hallidayi sp. n. from Anthochaera carunculata (Shaw) (type host) and A. chrysoptera (Latham); N. manorinae sp. n. from Manorina melanocephala (Latham); N. ophioglossus sp. n. from Conopophila rufogularis (Gould) (type host) and Lichmera indistincta (Vigors and Horsfield); and N. walteri sp. n. from Anthochaera phrygia (Shaw). A key to species and a world checklist to Neodectes species are provided for the first time. A new combination, Neodectes dicranochaetus (Gaud, 1968) comb. n., is proposed for Proterothrix dicranochaeta Gaud, 1968, which is transferred herein to the genus Neodectes from Proterothrix Gaud, 1968 (Proctophyllodidae).

Two new species of feather mites (Acariformes, Astigmata) from the black-tailed godwit, Limosalimosa (Charadriiformes, Scolopacidae), in Korea.

Two new species of feather mites are described from two individuals of the black-tailed godwit, Limosalimosa (Linnaeus, 1758), in Korea: Alloptes (Conuralloptes) neolimosaesp. nov. (Analgoidea, Alloptidae) and Phyllochaetalimosae sp. nov. (Pterolichoidea, Syringobiidae). Males of A. (C.) neolimosaesp. nov. are distinguished from A. (C.) limosae in having the hysteronotal shield with a straight anterior margin, setae h2 enlarged and slightly flattened in the basal half, and the terminal lamella monotonously transparent without sclerotized patches; females differ in having legs IV with ambulacral discs extending to or slightly beyond the level of setae f2. The discovery of P.limosae sp. nov. represents the first record of the feather mite genus Phyllochaeta on godwits of the genus Limosa Brisson, 1760 (Scolopacidae, Limosinae). Males of P.limosae sp. nov. are distinguished from P.secunda in having the terminal cleft semi-ovoid with a length-to-width ratio of 1.7, and the terminal membranes with 15 or 16 finger-shaped denticles; females differ in having the hysteronotal shield bearing faint longitudinal striations in the posterior third and lacking lacunae, and setae c1 situated posterior to the level of setae c2. Additionally, we obtained partial sequences of the mitochondrial cytochrome c oxidase subunit I (COI) gene from A. (C.) neolimosaesp. nov. and estimated genetic distances from 10 other Alloptes species based on comparisons of COI sequences.

Panoramic Endocardial Optical Mapping Demonstrates Serial Rotors Acceleration and Increasing Complexity of Activity During Onset of Cholinergic Atrial Fibrillation.

Background Activation during onset of atrial fibrillation is poorly understood. We aimed at developing a panoramic optical mapping system for the atria and test the hypothesis that sequential rotors underlie acceleration of atrial fibrillation during onset. Methods and Results Five sheep hearts were Langendorff perfused in the presence of 0.25 µmol/L carbachol. Novel optical system recorded activations simultaneously from the entire left and right atrial endocardial surfaces. Twenty sustained (>40 s) atrial fibrillation episodes were induced by a train and premature stimuli protocol. Movies obtained immediately (Initiation stage) and 30 s (Early Stabilization stage) after premature stimulus were analyzed. Serial rotor formation was observed in all sustained inductions and none in nonsustained inductions. In sustained episodes maximal dominant frequency increased from (mean±SD) 11.5±1.74 Hz during Initiation to 14.79±1.30 Hz at Early Stabilization (P<0.0001) and stabilized thereafter. At rotor sites, mean cycle length (CL) during 10 prerotor activations increased every cycle by 0.53% (P=0.0303) during Initiation and 0.34% (P=0.0003) during Early Stabilization. In contrast, CLs at rotor sites showed abrupt decreases after the rotors appearances by a mean of 9.65% (P<0.0001) during both stages. At Initiation, atria-wide accelerations and decelerations during rotors showed a net acceleration result whereby post-rotors atria-wide minimal CL (CLmin) were 95.5±6.8% of the prerotor CLmin (P=0.0042). In contrast, during Early Stabilization, there was no net acceleration in CLmin during accelerating rotors (prerotor=84.9±11.0% versus postrotor=85.8±10.8% of Initiation, P=0.4029). Levels of rotor drift distance and velocity correlated with atria-wide acceleration. Nonrotor phase singularity points did not accelerate atria-wide activation but multiplied during Initiation until Early Stabilization. Increasing number of singularity points, indicating increased complexity, correlated with atria-wide CLmin reduction (P<0.0001). Conclusions Novel panoramic optical mapping of the atria demonstrates shortening CL at rotor sites during cholinergic atrial fibrillation onset. Atrial fibrillation acceleration toward Early Stabilization correlates with the net result of atria-wide accelerations during drifting rotors activity.

Feather mites of the subfamily Pterodectinae (Acariformes: Proctophyllodidae) from passerines and kingfishers in Canada.

Investigation of the diversity and taxonomy of feather mites of the subfamily Pterodectinae (Astigmata: Proctophyllodidae) on passerines (Passeriformes) and kingfishers (Coraciiformes: Alcedinidae) in Manitoba revealed 19 species in 5 genera. Of them, eight new species are described, seven of these from passerines and one from a kingfisher: Alaudicola eremophila sp. n. from Eremophila alpestris (Alaudidae), Amerodectes icteri sp. n. from Icterus galbula (Icteridae), A. pheucticus sp. n. from Pheucticus ludovicianus (Cardinalidae), A. tiffanyluiae sp. n. from Oporornis agilis (Parulidae), A. tretiakae sp. n. from Molothrus ater (Icteridae), Tyrannidectes sealyi sp. n. from Tyrannus tyrannus (Linnaeus, 1758) (type host) and Tyrannus verticalis Say, and T. empidonicus sp. n. from Empidonax minimus (Tyrannidae), and Proterothrix megaceryle sp. n. from Megaceryle alcyon (Alcedinidae). Additionally, nine pterodectine species are reported for the first time in the fauna of Canada. Based on re-evaluation of diagnostic charcters, new diagnoses are proposed for the genera Amerodectes, Tyrannidectes, and Metapterodectes, and species contents of these genera are revised. Four species are transferred from the genus Amerodectes to Tyrannidectes with the new combinations proposed: T. caribaeus (Mironov and Gonzlez-Acua, 2011) comb. n., T. charitomenos (Hernandes, 2018) comb. n., T. pitangi (Mironov, 2008) comb. n., T. vireonis (Hernandes and Pedroso, 2016) comb. n. Six species are transferred from the genus Tyrannidectes to Metapterodectes with the new combinations: M. amaurochalinus (Hernandes and Valim, 2006) comb. n., M. cinclodes (Mironov and Gonzlez-Acua, 2011) comb. n., M. crassus (Trouessart, 1885) comb. n., M. falcklandicus (Mironov and Gonzlez-Acua, 2011) comb. n., M. fissuratus (Hernandes and Valim, 2005) comb. n., and M. pteroptochi (Mironov and Gonzlez-Acua, 2015) comb. n.

Feather mites (Acariformes, Astigmata) from marine birds of the Barton Peninsula (King George Island, Antarctica), with descriptions of two new species.

We report on the first investigation of feather mites associated with birds living on the Barton Peninsula (King George Island, Antarctica). We found seven feather mite species of the superfamily Analgoidea from four host species. Two new species are described from two charadriiform hosts: Alloptes (Sternalloptes) antarcticussp. nov. (Alloptidae) from Stercorariusmaccormicki Saunders (Stercorariidae), and Ingrassiachionis sp. nov. (Xolalgidae) from Chionisalbus (Gmelin) (Chionidae). Additionally, we provide partial sequences of the mitochondrial cytochrome c oxidase subunit I (COI), which was utilized as a DNA barcode, for all seven feather mite species.

New feather mites of the Nycteridocaulus generic group (Acariformes: Proctophyllodidae) from passerines (Passeriformes) in Panama.

Three new feather mite species of the Nycteridocaulus generic group (Proctophyllodidae: Proctophyllodinae) are described from passerines in Panama: Atrichophyllodes myrmotherulae sp. n. from the Slaty Antwren, Myrmotherula schisticolor (Lawrence) (Thamnophilidae), Nycteridocaulus apanaskevichi sp. n. from the Grey-breasted Wood Wren, Henicorhina leucophrys (Tschudi) (Troglodytidae), and N. empidonicus sp. n. from the Yellowish Flycatcher Empidonax flavescens Lawrence (Tyrannidae). Nycteridocaulus apanaskevichi, presenting the second record of the genus from a host of oscine passerines, differs from N. guaratubensis Hernandes, 2014 in having the anterolateral extensions of the prodorsal shield rounded and the hysteronotal shield lacking any ornamentation. Males of N. empidonicus differ from N. myiobius Mironov, 2017 in having the supranal concavity open posteriorly and tarsus IV with rounded apical process; and females are distinguished by macrosetae h2 having long filiform apices. Males of A. myrmotherulae most clearly differ from A. mentalis Hernandes et al. 2007 in having the terminal lamellae rectangular and tarsus IV with triangular ventral process, and females are distinguished in having a noticeably longer idiosoma, 400-430 µm long. Comments on systematics and host associations of the genera Atrichophyllodes and Nycteridocaulus are provided.

Arthropod parasites of Antarctic and Subantarctic birds and pinnipeds: A review of host-parasite associations.

Due to its cold and dry climate and scarcity of ice-free land, Antarctica has one of the most extreme environments on our planet. To survive in the Antarctic region, parasitic arthropods must either remain closely associated with their hosts throughout the entire life cycle or develop physiological adaptations to survive in the terrestrial habitat while their hosts are away foraging at sea or overwintering at lower latitudes. Forty-eight species of birds and seven species of pinnipeds breed in the Antarctic region, with 158 species/subspecies of parasitic arthropods recorded thus far, comprising: sucking lice (Echinophthiriidae), chewing lice (Menoponidae, Philopteridae), fleas (Ceratophyllidae, Pygiopsyllidae, Rhopalopsyllidae), pentastomes (Reighardiidae), hard ticks (Ixodidae), nest-associated haematophagous mites (Laelapidae), nasal mites (Halarachnidae, Rhinonyssidae) and feather mites (Alloptidae, Avenzoariidae, Xolalgidae, Freyanidae). In this review, we provide an updated compilation of the available information on the host-parasite associations of arthropods infesting birds and pinnipeds in the Antarctic region, and discuss some over-arching ecological patterns and gaps of knowledge.

Feather mites of the genus Trouessartia (Acariformes: Trouessartiidae) from passerines (Aves: Passeriformes) in Georgia, USA.

Ten new species of the feather mite genus Trouessartia Canestrini, 1899 (Analgoidea: Trouessartiidae) are described from various passerines of the superfamily Passeroidea in Georgia: Trouessartia americana sp. n. from Setophaga americana (Linnaeus), T. helmitheros sp. n. from Helmitheros vermivorum (Gmelin, JF), T. mniotilta sp. n. from Mniotilta varia (Linnaeus), T. pensylvanica sp. n. from Setophaga pensylvanica (Linnaeus) (type host) and S. palmarum (Gmelin, JF), T. ruticilla sp. n. from S. ruticilla (Linnaeus), T. seiurus sp. n. from Seiurus aurocapilla (Linnaeus), T. tigrina sp. n. from Setophaga tigrina (Gmelin, JF) (Parulidae), T. passerinae sp. n. from Passerina caerulea (Linnaeus) (type host) and P. cyanea (Linnaeus), T. ciris sp. n. from P. ciris (Linnaeus) (Cardinalidae), and T. spizellae sp. n. from Spizella passerina (Bechstein) (Passerellidae). Based on a specific combination of morphological characters, all new species and six previously known species are arranged into a new species group capensis in the genus Trouessartia. The most important diagnostic characters of this species group include: in both sexes, the dorsal hysterosomal apertures are absent; in males, the postgenital plaque is well developed and genital setae g have cylindrical articulation rings; in females, the external copulatory tube is straight, stylet- or finger-like, and situated on the margin of the interlobar membrane, and the head of spermatheca has a semi-ovate extension without indentations. A key to all species referred to the capensis group is provided and host associations of this group with passerines are summarized and briefly discussed. It is hypothesized that this species group originated on the ancestors of New World nine-primaried oscines (Emberizoidea) and diverged in close relation with this group of hosts.

Feather mites of the genus Trouessartia Canestrini (Acariformes: Trouessartiidae) from swallows (Passeriformes: Hirundinidae) in Canada.

Seven species of the feather mite genus Trouessartia Canestrini, 1899 (Astigmata: Trouessartiidae) have been recorded on swallows and martins (Passeriformes: Hirundinidae) in Manitoba (Canada). Of them, five are described as new species: Trouessartia ampulicaudata sp. n. and T. petrochelidon sp. n. from the American cliff swallow Petrochelidon pyrrhonota (Vieillot), T. bochkovi sp. n. from the tree swallow Tachycineta bicolor (Vieillot), and T. cryptocaudata sp. n. and T. progne sp. n. from the purple martin Progne subis (Linnaeus). A new species group stelgidopteryx, incorporating Trouessartia species living on hirundinids of the genera Progne, Tachycineta and Stelgidopteryx, is established. Renewed diagnoses of four Trouessartia species groups (appendiculata, crucifera, minutipes, and stelgidopteryx) restricted to hirundinids and a key to species recorded so far and potentially expected on swallows of North America are proposed. Host associations of Trouessartia species with swallows in North America are briefly discussed.

Captive individuals of endangered Philippine raptors maintain native feather mites (Acariformes: Pterolichoidea) species.

Endangered species of hosts are coupled with endangered species of parasites, which share the risk of co-extinction. Conservation efforts sometimes include breeding of rare species in captivity. Data on parasites of captive populations of endangered species is scarce and the ability of small numbers of captive host individuals to support the biodiversity of native parasites is limited. Examination of ectosymbionts of the critically endangered Philippine eagles and the endangered Mindanao Hawk-Eagle kept at the Philippine Eagle Center, Philippines, revealed three feather mite species despite regular treatment with insecticide powder. No other ectosymbiont taxa were detected. Studies in morphology and molecular phylogeny of these feather mites based on mitochondrial and nuclear DNA markers indicate that species found were typical for Accipitridae. Three new pterolichoid feather mite species (Acari: Pterolichoidea) were described from two species of eagles (Accipitriformes: Accipitridae) endemic to the Philippines: Hieracolichus philippinensis sp. n. (Gabuciniidae) and Pseudalloptinus pithecophagae sp. n. (Pterolichidae) from the Great Philippine Eagle Pithecophaga jefferyi Ogilvie-Grant, 1896, and Pseudogabucinia nisaeti sp. n. (Kramerellidae) from the Mindanao Hawk-Eagle Nisaetus pinskeri Gould, 1863. The presence of H. philippinensis on P. jefferyi supports the recent finding that the Great Philippine Eagle belongs to the lineage of serpent eagles (Circaetinae) rather than to the Harpy and other eagles.

New feather mites of the genus Amerodectes Valim and Hernandes (Acariformes: Proctophyllodidae) from passerines (Aves: Passeriformes) in Georgia, USA.

Eight new species of the feather mite genus Amerodectes Valim and Hernandes, 2010 (Proctophyllodidae: Pterodectinae) are described from passerines (Aves: Passeriformes) in Georgia, USA: Amerodectes cathari sp. n. from Catharus ustulatus (Nuttall) (Turdidae), A. haemorhous sp. n. from Haemorhous mexicanus (Muller, PLS) (Fringillidae), A. helmitheros sp. n. from Helmitheros vermivorum (Gmelin) (Parulidae), A. hribari sp. n. from Geothlypis trichas (Linnaeus) (Parulidae), A. hylocichlae sp. n. from Hylocichla mustelina (Gmelin) (Turdidae), A. passerinae sp. n. from Passerina ciris (Linnaeus) (Cardinalidae), A. seiurus sp. n. from Seiurus aurocapilla (Linnaeus) (Parulidae), and A. spizellae sp. n. from Spizella passerina (Bechstein) (Emberizidae). An updated world checklist of Amerodectes species and a key to species recorded and potentially expected in North America (USA and Canada) are proposed.

Detecting ancient codispersals and host shifts by double dating of host and parasite phylogenies: Application in proctophyllodid feather mites associated with passerine birds.

Inferring cophylogeographic events requires matching the timing of these events on both host and symbiont (e.g., parasites) phylogenies because divergences of hosts and their symbionts may not temporally coincide, and host switches may occur. We investigate a large radiation of birds (Passeriformes) and their permanent symbionts, the proctophyllodid feather mites (117 species from 116 bird species; six genes, 11,468 nt aligned) using two time-calibration strategies for mites: fossils only and host phylogeography only. Out of 10 putative cophylogeographic events 4 agree in timing for both symbiont and host events being synchronous co-origins or codispersals; three were based on host shifts, but agree in timing being very close to the origin of modern hosts; two disagree; and one large basal mite split was seemingly independent from host phylogeography. Among these events was an ancient (21-25.3 Mya), synchronous codispersal from the Old World leading to the origin and diversifications of New World emberizoid passerids and their mites, the thraupis + quadratus species groups of Proctophyllodes. Our framework offers a more robust detection of host and symbiont cophylogeographic events (as compared to host-symbiont reconciliation analysis and using host phylogeography for time-calibration) and provides independent data for testing alternative hypotheses on timing of host diversification and dispersal.

Convergent and unidirectional evolution of extremely long aedeagi in the largest feather mite genus, Proctophyllodes (Acari: Proctophyllodidae): Evidence from comparative molecular and morphological phylogenetics.

Proctophyllodid feather mites (400+ species) are permanent (full-time) symbionts commonly occurring on passerine birds. Phenotypic evolution of these mites appears to be greatly influenced by characters related to reproduction (>87.5% of a total of 32 taxonomically important discrete characters) and male genitalic characters (21.9%). Because sexual selection could the major evolutionary driver in this system, we test the theoretical expectation that genitalic or sexually dimorphic characters should evolve more rapidly and divergently then other characters. We inferred a time-calibrated molecular phylogeny (6 genes, 8571 nt aligned, no missing data) for 133 taxa of proctophyllodid mites and 40 outgroups. Comparisons of the average number of character state changes inferred on 10,696 Bayesian stationary trees indicate that male genitalic or sexually dimorphic characters do not evolve significantly faster than other characters (p=0.537 and p=0.819, respectively). However, among the male genitalic characters, a trait related to the relative length of the aedeagus experienced extremely fast rates of evolution and was detected as a statistical outlier. In this character, the transitions between short, long, and several intermediate states occurred in both directions. In contrast, the evolution of extremely long aedeagi (nearly as long as the body) occurred unidirectionally and irreversibly. This surprising result may be due to constraints imposed by the female spermathecal canal, which, in species where males have extremely long aedeagi, is also very long and may impede pumping sperm by short aedeagi. In proctophyllodid mites, extremely long aedeagi evolved independently five times in five different monophyletic lineages. Several of these lineages were lumped together by taxonomists to form easy-to-distinguish but apparently artificial species-groups. Male genitalic characters, thus, can introduce false synapomorphies that could affect morphology-based phylogenetic inference. For the most species-rich genus, Proctophyllodes, we develop a predictive classification of species-groups that reconciles molecular and morphological data.

Feather mites of the genera Dubininia and Cacatualges (Acari: Xolalgidae) associated with parrots (Aves: Psittaciformes) of the Old World.

This paper gives a systematic revision of feather mites of the genera Dubininia Vassilev, 1958 and Cacatualges Dabert, Badek and Skoracki, 2007 (Xolalgidae: Ingrassiinae) associated with parrots (Aves: Psittaciformes) of the Old World. Five new species are described: Cacatualges probosciger sp. n. from Probosciger aterrimus (Gmelin) (Cacatuidae) from New Guinea, Dubininia charmosynae sp. n. from Charmosyna pulchella Gray GR (Psittaculidae) from New Guinea, D. micropsittae sp. n. from Micropsitta pusio pusio (Scaltter) (Psittaculidae) from New Guinea, D. nestori sp. n. from Nestor notabilis Gould (Strigopidae) from New Zealand, and D. pezopori sp. n. from Pezoporus wallicus (Kerr) (Psittaculidae) from Tasmania, Australia. Four previously described species of Dubininia are redescribed based on material from type hosts: D. curta (Trouessart, 1885) from Platycercus elegans (Gmelin) (Psittaculidae), D. lorina (Trouessart, 1885) from Lorius domicella (Linnaeus) (Psittaculidae), D. melopsittaci Atyeo and Gaud, 1987 from Melopsittacus undulatus (Shaw) (Psittaculidae), and D. psittacina (Trouessart, 1885) from Strigops harboptilus Gray GR (Strigopidae) from New Zealand. A new diagnosis for the genus Dubininia is provided. A key to all presently known Dubininia species is provided for the first time.

Two new feather mites of the genus Proctophyllodes Robin, 1868 (Acari: Proctophyllodidae) from European passerines (Aves: Passeriformes).

Two new species of the feather mite genus Proctophyllodes Robin, 1868 (Analgoidea: Proctophyllodidae) are described from two passerine birds (Passeriformes) in Europe: Proctophyllodes markovetsi n. sp. from the tawny pipit Anthus campestris (L.) (Motacillidae) and P. loxiae n. sp. from the red crossbill Loxia curvirostra (L.) (Fringillidae). Males of P. markovetsi are most clearly distinguished from the closely related P. tchagrae Atyeo & Braasch, 1966 by having greater terminal lamellae (30-40 × 20-25 µm), the tips of genital arch curved medially, and the corolla of the anal sucker with 14-15 denticles; females of this species are characterised by the terminal appendages distinctly longer than the lobar region width. Males of P. loxiae differ from the closest species, P. fuchsi Mironov, 1997, by having smaller terminal lamellae (45-50 × 22-28 µm), the genital organ extending beyond the posterior margin of lamellae by half their length; females can be distinguished by having the terminal cleft noticeably wider than long (28-30 × 35-40 µm).

A new feather mite of the genus Neodectes Park and Atyeo 1971 (Acari: Proctophyllodidae) from New Zealand wrens (Passeriformes: Acanthisittidae).

A new feather mite species, Neodectes pilgrimi sp. n. (Proctophyllodidae: Pterodectinae), is described from three species of New Zealand wrens (Passeriformes: Acanthisittidae): Xenicus gilviventris Pelzeln, 1867 (type host), X. longipes (Gmelin, 1789) (extinct species), and Acanthisitta chloris (Sparrman, 1787). Based on known host associations of the genus Neodectes, it is hypothesized that Neodectes pilgrimi sp. n. has a secondary origin on New Zealand wrens and was probably transferred onto the ancestor of its hosts from honeyeaters (Passeriformes: Meliphagidae).

A new feather mite of the genus Trouessartia Canestrini 1899 (Acariformes: Trouessartiidae) from the Seychelles magpie-robin, Copsychus sechellarum (Passeriformes: Muscicapidae).

A new feather mite species, Trouessartia sechellarum sp. n. (Astigmata: Analgoidea: Trouessartiidae), is described from the Seychelles magpie-robin Copsychus sechellarum (Passeriformes: Muscicapidae), an endangered endemic passerine bird inhabiting the Seychelles Islands. The most clear features distinguishing this mite from the related species, T. microfolia Gaud, 1952, are as follows: in both sexes, setae c2 do not exceed 30 µm and are subequal in length to setae c3 and sRIII; in males, the hysteronotal shield is completely split into the prohysteronotal and lobar parts by a narrow groove, and the terminal lamellae are attenuate apically; in females, the median part of the hysteronotal shield bears numerous ovate lacunae, the terminal cleft width is approximately equal to the opisthosomal lobe width, and the collar of the spermathecal head is smooth.

A new feather mite of the genus Pteronyssoides Hull, 1931 (Astigmata: Pteronyssidae) from thrushes (Passeriformes: Turdidae) in the New World.

A new feather mite species, Pteronyssoides turdinus n. sp. (Acariformes: Pteronyssidae), is described from two species of thrushes, Turdus amaurochalinus Cabanis (type-host) and T. leucomelas Vieillot (Passeriformes: Turdidae) in Minas Gerais, Brazil. The new species belongs to the parinus species group and most clearly differs from previously known species of this group by the following features: in both sexes of P. turdinus, setae c2 are anterior to the level of the sejugal furrow; in males, the anterior margin of the hysteronotal shield has a deep trapezoidal concavity, setae d1 are situated on the striated tegument, the adanal shield is represented by a narrow longitudinal sclerite, and tarsus and tibia of legs IV are subequal in length; in females, the opisthosomal sclerites are split into proper opisthosomal sclerites and pygidial fragments encompassing the bases of setae h2 and h3. This is the first description of a feather mite of the genus Pteronyssoides Hull, 1931 from birds of the family Turdidae.