Geology topics

Danny B. Pence

Publications and source records attributed to Danny B. Pence.

4 recordsLinked to original sources

USGS1999

Epizootic podoknemidokoptiasis in American robins

Epizootics of scaly leg disease caused by infection with the submacroscopic mite Knemidokoptes jamaicensis (Acari: Knemidokoptidae) in migratory American robins ( Turdus migratorius ) from a residential area of Tulsa (Oklahoma, USA) are documented during the winters (December through February) of 1993–94 and 1994–95. Estimates of 60 to >80% of the birds in several different flights arriving in the area had lesions consistent with knemidokoptic mange. Epizootic occurrence of K. jamaicensis also is confirmed incidentally in American robins from Georgia (USA) in 1995 and 1998 and in Florida (USA) in 1991. These are the first confirmed epizootics of scaly leg attributed to infections with mites specifically identified as K. jamaicensis in North America. Severity of observed lesions in American robins ranged from scaly hyperkeratosis of the feet and legs to extensive proliferative lesions with loss of digits or the entire foot in some birds. Histologically, there was severe diffuse hyperkeratosis of the epidermis which contained numerous mites and multifocal aggregates of degranulating to degenerating eosinophilic heterophils; there was mild to severe superficial dermatitis with aggregates of eosinophilic heterophils and some mononuclear cells. Based on limited data from affected captive birds in Florida, we questioned the efficacy of ivermectin as an effective acaricide for knemidokoptiasis and propose that conditions associated with captivity may exacerbate transmission of this mite among caged birds. While knemidokoptic mange apparently can result in substantial host morbidity and possibly mortality, the ultimate impact of these epizootics on American robin populations presently is unknown.

Florida, Georgia, Oklahoma↗

USGS1997

New records with examples of potential host colonization events for hypopi (Acari: Hypoderatidae) from birds

New host, geographic records, or both are established for 14 species of hypoderatid deutonymphs from 14 species of birds in North America. Ten of these records are regarded as examples of a potential host colonization event where these hypopi have become established in hosts other than those with which they are normally associated. Herein, potential host colonization events by hypoderatid deutonymphs are regarded as more of an ecologically determined than physiologically specific phenomenon, often specifically related to sharing of nesting sites in the same rookeries by different host taxa. Neottialges ibisicola Young & Pence is placed as a junior synonym of Neottialges plegadicola Fain. The taxonomic status of Hypodectes propus from columbid versus ardeid hosts needs further study.

Journal of Medical Entomology↗

USGS1995

Hypopi (Acari: Hypoderatidae) of the wood stork (Aves: Ciconiiformes: Ciconiidae)

A new species is described and additional host records are presented for 2 other species of deutonymphs of the family Hypoderatidae from the subcutaneous adipose tissues of the wood stork, Mycteria americana L. Phalacrodectes (Phalacrodectes) mycteria n. sp. appears to share affinities with species from both pelicaniform and ciconiiform hosts, but it most closely resembles P. (P.) punctatissimus (Černý) Pence & Courtney from pelicans in idiosomal chaetotaxy, cutdcular sclerotization, and posteriorly divergent, widely separated genital openings. The new species differs from this and other species of the genus by its small size, the degree of separation of the genital openings with papillae, no secondary sclerotization in the perigenital area or surrounding the genital openings, and the long filiform setae s and w on genu III. There was a mixed infection of Neottialges kutzeri Fain and N. mycteriae Pence in all of 7 wood storks examined from Florida and Georgia; P. (P) mycteria was found in 4 of these hosts. This is the 7th species described as a deutonymph in the genus Phalacrodectes . The apparent close affinity of P. (P.) mycteria with P. (P.) punctatissimus and allied species from pelicaniform versus ciconiiform birds appears to be inconsistent with the established host-parasite relationships based on classical avian taxonomic relationships. However, this apparent affinity may be more reflective of the close relationships between the families of pelicans, ibises and spoonbills, and storks as recently proposed by DNA–DNA hybridization studies.

Florida, Georgia↗

USGS1995

First record of an hypopus (Acari: Hypoderatidae) from a jaeger (Aves: Charadriiformes: Stercorariidae)

Thalassornectes (Alcidectes) aukletae, originally described from two species of auklets (Charadriiformes: Alcidae) from maritime eastern Russia, is reported from a third species of pelagic charadriiform (Stercorariidae), the pomarine jaeger, Stercorarius poinarinus (Temminck), from Florida. The specimens from the jaeger are slightly smaller, the genital apodeme is more heavily sclerotized, paired setae gm are twice as long and there are other minor variations in the idiosomal and leg chaetotaxy. These differences are not considered sufficient to warrant taxonomic separation at the species or subspecies level from the nominate species T. (A.) aukletae. The same hypopus occurring across different families of birds is unusual in the Hypoderatidae. The diversity in hosts from several orders of birds, low intensities of infection in the two species from Africa, low prevalences in alcids from Russia, and rarity of these hypoderatids in all surveyed hosts leads us to speculate that the true host affinities of species in the genus Thalassornectes are unknown. The alternative consideration is that these are simply uncommon species that are very host specific.

Florida↗