Research Article |
Corresponding author: Wayne Knee ( whknee@gmail.com ) Academic editor: Farid Faraji
© 2018 Wayne Knee.
This is an open access article distributed under the terms of the CC0 Public Domain Dedication.
Citation:
Knee W (2018) New species of parasitic nasal mites infesting birds in Manitoba, Canada (Mesostigmata, Rhinonyssidae). ZooKeys 786: 1-17. https://doi.org/10.3897/zookeys.786.28767
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Mites (Acari, Acariformes, Parasitiformes) are one of the most diverse and abundant groups of arthropods associated with birds. Several families of mites have colonised the respiratory tract of birds, the Rhinonyssidae (Mesostigmata) being the most diverse. There are 66 species of rhinonyssids (59 named, seven undescribed species) reported from Canadian birds. Two new species of rhinonyssids were discovered while surveying nasal mites from birds in Manitoba, Canada, and are herein described as Sternostoma gallowayi sp. n. from the horned lark (Eremophila alpestris), and Vitznyssus erici sp. n. from the common nighthawk (Chordeiles minor).
Acari , alpha taxonomy, mite, nasal mite, parasite
Birds are hosts to a hyperdiverse assemblage of symbiotic animals, residing in all conceivable habitats. Mites are one of the most diverse and frequently encountered associates of birds, with at least 40 families and 2500 described species that live in close association with birds (
Mites inhabit all parts of the avian integument; they can be found on and in the skin of their hosts, on and in feathers, and in the respiratory tract. Five families of acariform (Cloacaridae, Ereynetidae, Turbinoptidae, Cytoditidae) and parasitiform (Rhinonyssidae) mites, have evolved independently to be parasitic in the nasal passages or lungs of birds. There are at least 500 described species of nasal mites worldwide (
Nasal mites have been surveyed in many geographic regions throughout the world (
Injured and sick birds were submitted to the Wildlife Haven (Manitoba Wildlife Rehabilitation Organization) and the Prairie Wildlife Rehabilitation Centre, mostly by members of the public, and after death they were stored at -20 °C until processing in TD Galloway’s lab at the University of Manitoba (Winnipeg, Manitoba, Canada). The nasal passages of thawed birds were flushed with a solution of warm water and mild soap using a 12 mL Monojet® 412 curved tip orthodontic plastic syringe. The solution was flushed through each nostril, through the opening in the palette and back out the mouth into a Petri dish. Occasionally nasal mites were collected from whole-body washing, where a thawed bird was placed in a container ranging in volume from 4–40 L, depending on the size of the bird, submerged in warm water containing a few drops of liquid dish detergent. Each bird was agitated vigorously three to 10 minutes, depending on the size of the bird. Each bird was then removed from the container and rinsed thoroughly; the washing solution was filtered through a 90 µm sieve. This process was repeated once again with warm, soapy water, and once finally with warm water. The filtrate from all three washes was preserved in 70 or 95% ethanol. Samples were examined for mites using a dissecting microscope. All nasal mites were collected and preserved in 70 or 95% ethanol for later identification.
Mites were removed from ethanol and cleared in 85% lactic acid, mounted in polyvinyl alcohol medium (6371A, BioQuip Products, Rancho Dominguez, California, United States of America), and cured on a slide warmer at 40 °C for 3–4 days. Slide-mounted specimens were examined using a Leica DM2500 compound microscope and Leica ICC550 HD camera, with differential interference contrast illumination (DIC). Initial drawings of mites were made with pencil on paper using a camera lucida. Illustrations were later merged in Adobe Photoshop CS5 and redrawn in Adobe Illustrator CS5 using an Intuos 3 Graphics Tablet from WACOM Co., Ltd. (Saitama, Japan). Leg chaetotaxy is based on the system proposed by
Type specimens are deposited in the Canadian National Collection of Insects, Arachnids, and Nematodes (Agriculture and Agri-Food Canada, Ottawa, Ontario, Canada). Host taxonomy follows
Sternostoma cryptorhynchum Berlese & Trouessart, 1889.
Diagnosis. Stigmata dorsal or lateral, without peritreme. Gnathosoma ventral, only partially visible dorsally. Cheliceral digits small, less than one tenth the length of the chelicerae. One or two dorsal plates. Sternal and anal plates usually present.
Type material. Holotype: female (CNC535681) from horned lark (WK357), Eremophila alpestris, Winnipeg, Manitoba, Canada, 22.x.2011, coll: T.D. Galloway. Paratypes: female (CNC991940) same collection information as holotype. Two females (CNC991941, CNC991942) from horned lark (WK625), Winnipeg, Manitoba, Canada, 5.viii.2014, coll. TD Galloway.
Diagnosis female. Dorsum with two shields, podosomal shield large, covering most of podosoma with eight pairs of minute setae and two pairs of pore-like structures, opisthosomal shield medium-sized with two pairs of minute setae and four pairs of pore-like structures. Two pairs of minute setae in dorsal opisthosomal unsclerotised integument. Paranal setae on anal shield level with anus, postanal seta absent. Sternal shield longer than wide, three pairs of sternal setae (st1–3) on shield. Genital shield slightly reticulated lengthwise, broadly rounded posteriorly, seta st5 on genital shield. Four pairs of minute setae in ventral opisthosomal unsclerotised integument. Ventral subcapitulum without setae. Ventrolateral and apical setae on tarsus II–IV thickened, baculiform and slightly curved distally.
Description female. Dorsal idiosoma (Figs
Ventral idiosoma (Figure
Gnathosoma (Figure
Legs (Figure
Male and immatures. unknown
This species is named after Dr. Terry D Galloway, who has tirelessly collected nasal mites and other bird-associated arthropods for many years, and has given me the opportunity to continue my studies of these unique mites.
Remarks. The female of Sternostoma gallowayi sp. n. is most similar to those of S. sialiphilus Hyland and Ford, and S. loxiae Fain. These species each have two dorsal shields which are similar in extent and shape, enlarged and elongated ventrolateral and apical setae on tarsus II–IV, no setae in the unsclerotised dorsal podosomal integument, four pairs of setae in the ventral opisthosomal integument, two or less pairs of setae in the dorsal opisthosomal integument, and lack a postanal seta. Sternostoma sialiphilus has been collected from the bank swallow (Riparia riparia) in Canada, and the eastern bluebird (Sialia sialis) in the United States (
Female S. gallowayi can be distinguished from that of S. sialiphilus and S. loxiae by having eight pairs of setae and two pairs of pores on the podosomal shield, S. sialiphilus has nine pairs of setae, S. loxiae has seven pairs of setae; two pairs of setae and four pairs of pores on the opisthosomal shield, S. sialiphilus has one pair of setae and three pairs of pores, S. loxiae has three pairs of setae and two pairs of pores on the shield; two pairs of setae in the dorsal opisthosomal unsclerotised integument, S. sialiphilus and S. loxiae have one pair; paranal setae level with anus, S. sialiphilus and S. loxiae the paranal setae are posterior to the anus; baculiform ventrolateral and apical setae on tarsus II–IV which are not distally inflated, S. sialiphilus and S. loxiae have distally inflated ventrolateral and apical setae on tarsus II–IV. Sternostoma gallowayi differs specifically from S. sialiphilus by the presence of seta st5 on the genital shield, which is absent in S. sialiphilus, and the absence of contiguous alveoli between the podosomal and opisthosomal shields which are present in S. sialiphilus. Sternostoma gallowayi differs specifically from S. loxiae by having slight reticulation lengthwise on the genital shield, this reticulation is well-developed in S. loxiae (
Horned larks are not commonly submitted to wildlife rehabilitation hospitals in Manitoba. Only six specimens have been submitted since 1994, five of which were examined for nasal mites. Of these, two were infested with S. gallowayi.
Dermanyssus nitschi Giebel, 1871 (=Vitznyssus caprimulgi (Fain, 1957))
Female mites of Vitznyssus species are defined by
Vitznyssus is a small genus comprised of seven species collected from two disparate orders of birds: V. afrotis (Fain), V. neotis (Fain), V. tetragis Butenko, V. vitzthumi (Fain) from Otididae, Gruiformes; V. caprimulgi (Fain), V. scotornis (Fain), and V. tsachevi Dimov and Rojas from Caprimulgidae, Caprimulgiformes (
Large mite with one dorsal shield, podosomal shield longer than wide, rounded anteriorly, constricted posteriorly with irregular margins posterolaterally, six pairs of setiform setae, vacuolate areas and irregular transverse lines on podosomal shield. Subposterior setal pair on podosomal shield elongate, nearly twice as long as all other podosomal shield setae. Four pairs of setiform setae lateral and posterolateral of podosomal shield. Doral and ventral hysterosoma without small shieldlets. Sternal shield small, poorly sclerotised, constricted posteriorly, seta st1 and lyrifissure iv1 on sternal shield, setae st2, st3, and lyrifissure iv2 off sternal shield. Genital shield elongate and narrow with parallel sides, seta st5 off genital shield. Paranal setae setiform with filamentous tip anterior to anus, postanal seta setiform with filamentous tip slightly shorter than paranal setae. Well-developed tritosternum with paired laciniae. Palp apotele two-tined with bifid tips.
Dorsal idiosoma (Figure
Ventral idiosoma (Figure
Gnathosoma (Figure
Legs (Figure
Male and immatures. Unknown.
This species is named after Eric Shewchuk, a close friend who has been beside me throughout the entirety of my studies on mites.
The female of Vitznyssus erici sp. n. is most similar that of V. afrotis Fain, which was described from the southern black bustard (Afrotis afra) in South Africa (
Female V. erici differ from that of V. afrotis by: the presence of irregular transverse lines on the podosomal shield, which are absent in V. afrotis; the posterolateral margins of the podosomal shield are more eroded, invaginated and irregular than that of V. afrotis; the anterior margin of the podosomal shield is broadly rounded with no setae in the integument anterior of the shield, the anterior margin is slightly eroded in V. afrotis and a pair of setae are off the shield anteriorly; the sternal shield is larger, with a posteromedial projection, and lyrifissure iv1 is on the shield, V. afrotis sternal shield is smaller and without a posteromedial projection, iv1 is off the shield; the genital shield margins are parallel and not flared posteriorly like they are in V. afrotis; and by the absence of small accessory shieldlets on the dorsal or ventral hysterosoma, which are present in V. afrotis.
Including V. erici there are now four Vitznyssus species known from Otididae (bustards) and four species known from Caprimulgidae (nightjars) hosts. Bustards only occur in the Eastern Hemisphere, while nightjars are broadly distributed in both hemispheres. Considering the geographic distribution of these mites and the disparate host bird orders, the monophyly of the genus and species boundaries should be investigated using molecular markers and morphometric analyses.
The common nighthawk (Chordeiles minor) has been a focus for studies of ectoparasites in Manitoba (
I thank the hospital staff at the Wildlife Haven (Manitoba Wildlife Rehabilitation Organization) and the Prairie Wildlife Rehabilitation Centre for their care in receiving birds, and their careful triage and processing protocols to maintain specimens in the best condition possible for this study. I am grateful to T.D. Galloway, Department of Entomology, Faculty of Agricultural and Food Sciences at the University of Manitoba for processing birds and collecting mites. I also thank Dave Holder, Lisa Babey, and a small army of undergraduate research assistants for their help in sampling for nasal mites. I thank J. Hsiung for redrawing the described species in Adobe Illustrator. I thank the Royal Belgian Institute for Natural Sciences for loaning type material.