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Search Results: 1 - 10 of 11301 matches for " George Poinar "
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Review of "Hemoparasites of the Reptilia. Color Atlas and Text" by Sam R. Telford, Jr
George Poinar
Parasites & Vectors , 2009, DOI: 10.1186/1756-3305-2-40
Abstract: This work presents a fascinating and detailed view of blood parasites (hemoparasites) of reptiles. As indicated by the author, the aim of this work is to compile all of the published data on the morphology of reptilian unicellular parasites. This is supplemented by unpublished data acquired by the author, his students and colleagues during the past 45 years. Included are morphometric descriptions of species of plasmodiids, hemogregarines, hemococcidians, trypanosomatids, piroplasmorids and miscellaneous blood parasites from lizards, snakes, turtles, crocodilians and even the tuatara. Over half of the text deals with malarial parasites of the genera Plasmodium, Haemocystidium and Saurocytozoon.The species descriptions are easy to follow since they are standardized under the headings of diagnosis, hosts, geographic distribution, prevalence, morphological variation, sporogony and effects on the host. The criteria for species determination appear to be based mainly on the morphology of the various parasite stages and their position within the host cells. In many cases, differences are obvious in the accompanying color plates, while in others, the degree of variation appears to overlap with that of closely related species. The ability to distinguish between the developmental stages of these parasites certainly comes with experience.While one might be tempted to use host records to identify hemoparasites, it is preferable to also examine morphological characters when attempting a specific determination.General sections in the book are separated by host and geographical range (e.g. Plasmodium species of Neotropical lizards, etc.), which allows researchers to turn to a particular locality in determining what type of infections occur there or what they may have discovered.Some host-parasite associations included in this work are surprising. Parasitologists have been stating for years that crocodilians do not get malaria, however, included in the present work is a plasmodiid
Lutzomyia adiketis sp. n. (Diptera: Phlebotomidae), a vector of Paleoleishmania neotropicum sp. n. (Kinetoplastida: Trypanosomatidae) in Dominican amber
George Poinar
Parasites & Vectors , 2008, DOI: 10.1186/1756-3305-1-22
Abstract: Lutzomyia adiketis sp. n. (Phlebotomidae: Diptera) is described from Dominican amber as a vector of Paleoleishmania neotropicum sp. n. (Kinetoplastida: Trypanosomatidae). The fossil sand fly differs from all previously described extinct and extant members of the genus by the following combination of characters: Sc forked with the branches meeting the costa and radius veins; wing L/W value of 4.1; a δ value of 18; a ratio β/α value of 0.86, and the shape and size of the spatulate rods on the ninth sternite. The trypanosomatid is characterized by the structure of its promastigotes, amastigotes and paramastigotes and its transmission by an extinct species of sand fly.Morphological characters show that the fossil sand fly is a new extinct species and that it is host to a digenetic species of trypanosomatid. This study provides the first fossil evidence that Neotropical sand flies were vectors of trypanosomatids in the mid-Tertiary (20–30 mya).Moth flies (Psychodidae) and sand flies (Phlebotomidae) are primitive Diptera [1] often treated as subfamilies [2]. The fossil record of sand flies dates back to Early Cretaceous Lebanese [3,4] and Burmese amber [5]. The Burmese amber sand fly, Palaeomyia burmitis Poinar [5] was transmitting Paleoleishmania protera Poinar & Poinar [6,7], the first described fossil digenetic trypanosomatid parasite. The present study describes a second species of Paleoleishmania carried by an extinct species of Lutzomyia sand fly in Dominican amber.Family Phlebotomidae Kertész 1903Genus Lutzomyia Fran?a 1924Lutzomyia adiketis sp.n. (Figs. 1, 2, 3, 4)Length = 1.3 mm; body, legs and antennae light brown.Head; Length, 315 μm; eye bridge absent; length of proboscis, 202 μm; maxillary palp extending well beyond tip of proboscis; length of maxillary palp, 544 μm; palpal formula 1-4-2-3-5; Newstead's scales in oval area on basal half of 3rd palpomere; lengths of palpomeres; 1, 44 μm; 2, 89 μm; 3, 120 μm; 4, 82 μm; 5, 209 μm; ratio of palp segments, 1/2 = 0
Review of "Primate Parasite Ecology: The dynamics and study of host-parasite relationships" by Michael A. Huffman and Colin A. Chapman (Eds.)
George Poinar
Parasites & Vectors , 2009, DOI: 10.1186/1756-3305-2-49
Abstract: No one can doubt that disease played a major role in human history and still continues to impact human health. Also, many human diseases, such as HIV, Ebola and malaria, have been acquired from our close primate relatives. The potential transmission of infectious agents from monkeys and apes to humans is why the study of primate parasites is so significant. The present work, which is divided into several Parts, consists of 25 chapters authored by one or more of 62 contributors.Part 1 deals with methods used in studying primate parasite interactions. It begins with a chapter on collecting and diagnosing primate parasites. This is followed with a chapter on extracting and identifying minute nematodes, mostly pin worms, recovered from fecal samples. The next chapter discusses the use of molecular methods for comparing populations of stomach worms (Oesophagostomum). This is followed by a discussion on the use of endocrinological analyses to interpret social relationships, anthropogenic disturbances and nutrition of primates. Part 1 ends with a chapter on the use of agent-based modeling to investigate the role played by infectious diseases of primates.Part 2 covers the natural history and host interactions of primate parasites. The first chapter discusses the behavior of gasterointestinal parasites in relation to host finding and parasite migrations. This is followed by a chapter on the evolution of adaptation and species jumping in primate malaria. Since there are over 30 species of primate Plasmodium malaria and at least 5 infect humans, this is an important topic. Whether the association of P. vivax and P. malariae with humans is ancient or recent is addressed and since both are closely related to New World monkey malaria, a strong case can be made for a transfer from monkey to humans. This scenario is strengthened by the discovery of a fossil Plasmodium from the Dominican Republic showing that Plasmodium malaria was in the New World 20-30 million years ago.The next c
Nematode Parasites and Associates of Ants: Past and Present
George Poinar Jr.
Psyche , 2012, DOI: 10.1155/2012/192017
Abstract: Ants can serve as developmental, definitive, intermediate, or carrier hosts of a variety of nematodes. Parasitic ant nematodes include members of the families Mermithidae, Tetradonematidae, Allantonematidae, Seuratidae, Physalopteridae, Steinernematidae, and Heterorhabditidae. Those nematodes that are phoretically associated with ants, internally or externally, are represented by the Rhabditidae, Diplogastridae, and Panagrolaimidae. Fossils of mermithids, tetradonematids, allantonematids, and diplogastrids associated with ants show the evolutionary history of these relationships, some of which date back to the Eocene (40 mya).
Vetufebrus ovatus n. gen., n. sp. (Haemospororida: Plasmodiidae) vectored by a streblid bat fly (Diptera: Streblidae) in Dominican amber
George O Poinar
Parasites & Vectors , 2011, DOI: 10.1186/1756-3305-4-229
Abstract: A new haemospororidan, Vetufebrus ovatus, n. gen., n. sp., (Haemospororida: Plasmodiidae) is described from two oocysts attached to the midgut wall and sporozoites in salivary glands and ducts of a fossil bat fly (Diptera: Streblidae) in Dominican amber. The new genus is characterized by ovoid oocysts, short, stubby sporozoites with rounded ends and its occurrence in a fossil streblid. This is the first haemosporidian reported from a streblid bat fly and shows that representatives of the Hippoboscoidea were vectoring bat malaria in the New World by the mid-Tertiary.This report is the first evidence of an extant or extinct streblid bat fly transmitting malaria. Discovering a mid-tertiary malarial parasite in a fossil streblid that closely resembles members of a malarial genus found in nycteribiid bat flies today shows how little we know about the vector associations of streblids. While no malaria parasites have been found in extant streblids, they probably occur and it is possible that streblids were the earliest lineage of flies that transmitted bat malaria to Chiroptera.Amber is known for its ability to preserve vertebrate microbial pathogens. Thus far, there are records of malaria, leishmaniasis and trypanosomiasis associated with insect vectors in amber deposits ranging from 20 to 100 million years of age [1]. Sporogonic stages of the bird malaria, Plasmodium dominicana, occurred in Culex malariager in Dominican amber [2] and developmental stages of Paleohaemoproteus burmacis (Haemospororida: Plasmodiidae) were reported from an Early Cretaceous Burmese amber biting midge (Diptera: Ceratopogonidae) [3]. The present study describes the sporogonic stages of a new genus of bat malaria in a Dominican amber fossil streblid [4]. Extant streblids have never been implicated as vectors of bat malaria, however members of the closely related family Nycteribiidae transmit bat malaria globally [5,6] (Table 1). Since both sexes of streblid bat flies (Diptera: Hippoboscoidea: St
Halophilanema prolata n. gen., n. sp. (Nematoda: Allantonematidae), a parasite of the intertidal bug, Saldula laticollis (Reuter)(Hemiptera: Saldidae) on the Oregon coast
George O Poinar
Parasites & Vectors , 2012, DOI: 10.1186/1756-3305-5-24
Abstract: Adults and last instar nymphs of S. laticollis (Hemiptera: Saldidae) were collected from the high intertidal zone among clumps of Juncus L. (Juncaceae) plants at Waldport, Oregon on October 3, 2011. The bugs were dissected in 1% saline solution and the nematodes killed in 1% Ringers solution and immediately fixed in 5% formalin (at 20°C). Third stage juveniles removed from infected hosts were maintained in 1% saline solution until they matured to the adult stage, molted and mated.Halophilanema prolata n. gen., n. sp. (Nematoda: Allantonematidae) is described from last instar nymphs and adults of the intertidal bug, Saldula laticollis on the Oregon coast. The new genus can be distinguished from other genera in the Allantonematidae by a stylet lacking basal knobs in both sexes, an excretory pore located behind the nerve ring, ribbed spicules, a gubernaculum, the absence of a bursa and the elongate-tubular shape of the ovoviviparous parasitic females. Studies of the organogenesis of Halophilanema showed development to third stage juveniles in the uterus of parasitic females. Maturation to the free-living adults and mating occurred in the environment. The incidence of infection of S. laticollis ranged from 0% to 85% depending on the microhabitat in the intertidal zone.Based on the habitat and morphological characters, it is proposed that Halophilanema adapted a parasitic existence fairly recently, evolutionarily speaking. It was probably a free-living intertidal or shore nematode that fed on microorganisms, especially fungi, in the intertidal habitat and became parasitic after saldids entered the environment. Halophilanema represents the first described nematode parasite of an intertidal insect.It is rare to find nematodes parasitizing arthropods inhabiting the intertidal or littoral zone of the oceans. This is an extremely harsh environment where the occupants are subjected to wave action, high salinity and open exposure. An exception is the mermithid, Thaumamermis zea
Description of an early Cretaceous termite (Isoptera: Kalotermitidae) and its associated intestinal protozoa, with comments on their co-evolution
George O Poinar
Parasites & Vectors , 2009, DOI: 10.1186/1756-3305-2-12
Abstract: A new species of termite (Kalotermes burmensis n. sp.) in Early Cretaceous Burmese amber had part of its abdomen damaged, thus exposing trophic stages and cysts of diverse protists. Some protists were still attached to the gut intima while others were in the amber matrix adjacent to the damaged portion. Ten new fossil flagellate species in the Trichomonada, Hypermastigida and Oxymonadea are described in nine new genera assigned to 6 extant families. Systematic placement and names of the fossil flagellates are based on morphological similarities with extant genera associated with lower termites. The following new flagellate taxa are established: Foainites icelus n. gen. n. sp., Spiromastigites acanthodes n. gen. n. sp., Trichonymphites henis n. gen., n. sp., Teranymphites rhabdotis n. gen. n. sp., Oxymonas protus n. sp., Oxymonites gerus n. gen., n. sp., Microrhopalodites polynucleatis n. gen., n. sp., Sauromonites katatonis n. gen., n. sp., Dinenymphites spiris n. gen., n. sp., Pyrsonymphites cordylinis n. gen., n. sp. A new genus of fossil amoeba is also described as Endamoebites proterus n. gen., n. sp. Fourteen additional trophic and encystid protist stages are figured and briefly characterized.This represents the earliest fossil record of mutualism between microorganisms and animals and the first descriptions of protists from a fossil termite. Discovering the same orders, families and possibly genera of protists that occur today in Early Cretaceous kalotermitids shows considerable behaviour and morphological stability of both host and protists. The possible significance of protist cysts associated with the fossil termite is discussed in regards the possibility that coprophagy, as well as proctodeal trophallaxis, was a method by which some termite protozoa were transferred intrastadially and intergenerationally at this time.Termites are one of the most successful eusocial insect groups today and certainly the most notorious as a result of their damage to human dw
Early Cretaceous trypanosomatids associated with fossil sand fly larvae in Burmese amber
Poinar Jr, George;
Memórias do Instituto Oswaldo Cruz , 2007, DOI: 10.1590/S0074-02762007005000070
Abstract: early cretaceous flagellates with characters typical of trypanosomatids were found in the gut of sand fly larvae, as well as in surrounding debris, in burmese amber. this discovery supports a hypothesis in which free-living trypanosomatids could have been acquired by sand fly larvae in their feeding environment and then carried transtadially into the adult stage. at some point in time, specific genera were introduced into vertebrates, thus establishing a dixenous life cycle.
Leptoconops nosopheris sp. n. (Diptera: Ceratopogonidae) and Paleotrypanosoma burmanicus gen. n., sp. n. (Kinetoplastida: Trypanosomatidae), a biting midge - trypanosome vector association from the Early Cretaceous
Poinar Jr., George;
Memórias do Instituto Oswaldo Cruz , 2008, DOI: 10.1590/S0074-02762008000500010
Abstract: leptoconops nosopheris sp. n. (diptera: ceratopogonidae) is described from a blood-filled female biting midge in early cretaceous burmese amber. the new species is characterized by a very elongate terminal flagellomere, elongate cerci, and an indistinct spur on the metatibia. this biting midge contained digenetic trypanosomes (kinetoplastida: trypanosomatidae) in its alimentary tract and salivary glands. these trypanosomes are described as paleotrypanosoma burmanicus gen. n., sp. n., which represents the first fossil record of a trypanosoma generic lineage.
J rg Wunderlich (ed.) (2012): Fifteen papers on extant and fossil spiders (Araneae). 368 pp. Beitr ge zur Araneologie 7.
Poinar, George Jr.
Arachnologische Mitteilungen , 2012, DOI: 10.5431/aramit4414
Abstract: book review
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