\u3ci\u3eRobustostrongylus aferensis\u3c/i\u3e gen. nov. et sp. nov. (Nematoda: Trichostrongyloidea) in Kob (\u3ci\u3eKobus kob\u3c/i\u3e) and Hartebeest (\u3ci\u3eAlcelaphus buselaphus jacksoni\u3c/i\u3e) (Artiodactyla) from Sub-saharan Africa, with Further Ruminations on the Ostertagiinae

Abomasal nematodes (Ostertagiinae: Trichostrongyloidea), representing a previously unrecognized genus and species, were discovered in kob (Kobus kob) and kongoni (hartebeest) (Alcelaphus buselaphus jacksoni) from Uganda during surveys of ungulate parasites in the 1960s. Robustostrongylus aferensis gen. nov. et sp. nov. is characterized by a ventriculus-like, bilobed valve at the junction of the esophagus and intestine, a synlophe with unusually robust ridges, cervical papillae and excretory pore situated posterior to the mid-length of the esophagus, a unique body form and large diameter in males and females, a relatively anterior position for the vulva, and strongly convoluted and spiraled ovarian tracks in females. Bursal structure is 2-1-2, with subequal Rays 2/3, strongly reduced and robust Rays 8, and relatively narrow Rays 9/10 contained within a reduced, laterally inflated dorsal lobe. Spicules are filamentous and tripartite; the gubernaculum is cryptic, alate, and heart-shaped in the anterior. Robustostrongylus aferensis, with narrow filamentous spicules that trifurcate distally near 80%, paired arcuate ‘‘0’’ papillae that terminate in bulbous expansions, and a reduced dorsal lobe and ray most closely resembles species of Longistrongylus. A suite of unique characters, consistent in males and females, however, unequivocally distinguishes specimens of R. aferensis from all ostertagiines with either a 2-1-2 or 2-2-1 bursal pattern. Among 15 genera of the Ostertagiinae in the global fauna, 5 are entirely limited in distribution to Africa, including Africanastrongylus, Hamulonema, Longistrongylus, Pseudomarshallagia, and Robustostrongylus gen. nov.; species among 5 additional genera, including Cervicaprastrongylus, Hyostrongylus, Marshallagia, Ostertagia, and Teladorsagia, also occur in Africa, but they are represented as mosaics, with diversity centered in Eurasia or the Holarctic

Why Museums Matter: A Tale of Pinworms (Oxyuroidea: Heteroxynematidae) among Pikas (\u3ci\u3eOchotona princeps\u3c/i\u3e and \u3ci\u3eO. collaris\u3c/i\u3e) in the American West [Critical Comment]

Permanent and well-supported museum or natural history collections provide a solid foundation for the process of systematics research through creation of an empirical record which validates our understanding of the biosphere. We explore the role of museums in ongoing studies of the complex helminth fauna characteristic of pikas (Ochotona spp.) in the American west. These studies address the taxonomy for pinworms of the Labiostomatinae and the problems associated with the absence of adequate type series and vouchers and with misidentifications in original descriptions. We demonstrate that the types for Labiostomum (Labiostomum) coloradensis are identical to some specimens in the syntype series representing L. (Eugenuris) utahensis, although the published descriptions are in disagreement. Both are identical to L. (Eugenuris) talkeetnaeuris and, as a consequence, are reduced as junior synonyms. Only two species of large pinworms, namely L. (Labiostomum) rauschi and L. (Eugenuris) talkeetnaeuris, are widely distributed in Ochotona collaris and O. princeps. Although this serves to clarify the taxonomy for species in these genera, prior records remain confused, as representative voucher specimens from all major surveys in North America were never submitted to museum collections. We strongly suggest that type and voucher series should not be held in private or personal collections, where such are eventually lost, discarded, or destroyed through neglect due to inattention and the absence of curation. The potential to accumulate meaningful baselines for assessment of environmental change is jeopardized if materials from survey and inventory are not routinely submitted to museum collections. The capacity of museum repositories, as a focus for systematics, ecology, and evolutionary studies and for the development of resources for biodiversity informatics, continues to be undervalued and poorly utilized by a cadre of scientists who are dependent on accurate and definitive information that transcends specific disciplines

Why Museums Matter: A Tale of Pinworms (Oxyuroidea: Heteroxynematidae) among Pikas (\u3ci\u3eOchotona princeps\u3c/i\u3e and \u3ci\u3eO. collaris\u3c/i\u3e) in the American West [Critical Comment]

Permanent and well-supported museum or natural history collections provide a solid foundation for the process of systematics research through creation of an empirical record which validates our understanding of the biosphere. We explore the role of museums in ongoing studies of the complex helminth fauna characteristic of pikas (Ochotona spp.) in the American west. These studies address the taxonomy for pinworms of the Labiostomatinae and the problems associated with the absence of adequate type series and vouchers and with misidentifications in original descriptions. We demonstrate that the types for Labiostomum (Labiostomum) coloradensis are identical to some specimens in the syntype series representing L. (Eugenuris) utahensis, although the published descriptions are in disagreement. Both are identical to L. (Eugenuris) talkeetnaeuris and, as a consequence, are reduced as junior synonyms. Only two species of large pinworms, namely L. (Labiostomum) rauschi and L. (Eugenuris) talkeetnaeuris, are widely distributed in Ochotona collaris and O. princeps. Although this serves to clarify the taxonomy for species in these genera, prior records remain confused, as representative voucher specimens from all major surveys in North America were never submitted to museum collections. We strongly suggest that type and voucher series should not be held in private or personal collections, where such are eventually lost, discarded, or destroyed through neglect due to inattention and the absence of curation. The potential to accumulate meaningful baselines for assessment of environmental change is jeopardized if materials from survey and inventory are not routinely submitted to museum collections. The capacity of museum repositories, as a focus for systematics, ecology, and evolutionary studies and for the development of resources for biodiversity informatics, continues to be undervalued and poorly utilized by a cadre of scientists who are dependent on accurate and definitive information that transcends specific disciplines

A New Species of Trichostrongyloid in African Buffalo (\u3ci\u3eSyncerus caffer\u3c/i\u3e) (Artiodactyla: Bovinae) from Uganda

Africanastrongylus giganticus n. sp. is described based on large ostertagiine nematodes occurring in the abomasum of African buffalo, Syncerus caffer, from Uganda; this represents the second species recognized in the genus. Specimens of A. giganticus are characterized by large size (15-19 mm in total length), a strongly tapering synlophe in the cervical region, and a great number of ridges at all levels of the body (maximum 72 attained in the third quarter); numbers of ridges exceed that reported among any known genera and species of the Ostertagiinae. We refer A. giganticus to this genus based on a strongly tapering lateral synlophe, relatively large numbers of ridges at all levels of the body, miniscule cervical papillae, poorly demarcated divisions of the ovejector, absence of vulval cuticular inflations, and the presence of slightly protruding lips at the vulva. It is distinguished from its congener, Africanastrongylus buceros, in total length, maximum number of ridges (68-72 vs. 53, respectively), structure and disposition of the synlophe, presence of strongly spiraled ovarian tracks, and eggs that are distributed in three or more rows in the uterus. A superficial resemblance to Longistrongylus meyeri, the only other large ostertagiine in the African fauna, is evident; these species, however, are distinct based on the synlophe and other characters. Recognition of a second species of Africanastrongylus represented by nematodes of large size suggests that prior reports of L. meyeri in Syncerus caffer may be attributable to A. giganticus

Synlophe Structure for Species of \u3ci\u3eLongistrongylus\u3c/i\u3e (Nematoda: Trichostrongyloidea), Abomasal Parasites among Ungulates from Sub-Saharan Africa, with Comparisons to the Global Ostertagiine Fauna

The synlophe, or system of longitudinal cuticular ridges characteristic of some trichostrongyloid nematodes, is examined in detail for 6 of 8 species in Longistrongylus (Ostertagiinae) that occur in ungulates across sub-Saharan Africa. Among the species of Longistrongylus examined, 5 are characterized by a tapering pattern laterally in the cervical zone (anterior to the esophageal-intestinal junction), which is largely consistent among multiple male and female specimens; in contrast, for Longistrongylus meyeri the lateral pattern is parallel. The synlophe is bilaterally symmetrical, with ridges extending from the base of the cephalic expansion to near the caudal extremity in males and females. Ridges are acutely pointed, with perpendicular orientation and absence of gradient as viewed in transverse section. Species-specific patterns in conjunction with the numbers of ridges may serve to augment an array of diagnostic characters for species of Longistrongylus and contribute to increasingly accurate identification of female specimens. Among 5 of 6 species examined in the current study, the numbers of ridges in males was equal to or exceeded that observed in females, a pattern seen only in Africanastrongylus among the 15 genera of the Ostertagiinae. The differential numbers of ridges in males and females may represent another character among the suite of attributes that in part diagnose the genus Longistrongylus,/i\u3e

Discovery and Description of the \u3ci\u3eDavtiani\u3c/i\u3e Morphotype for \u3ci\u3eTeladorsagia boreoarcticus\u3c/i\u3e (Trichostrongyloidea: Ostertagiinae) Abomasal Parasites in Muskoxen, \u3ci\u3eOvibos moschatus\u3c/i\u3e, and caribou, \u3ci\u3eRangifer tarandus\u3c/i\u3e, from the North American Arctic: Implications for Parasite Faunal Diversity

Collections to explore helminth diversity among free-ranging ungulates in the North American Arctic revealed the occurrence of a third male, or davtiani, morphotype for Teladorsagia boreoarcticus. Designated as T. boreoarcticus forma (f.) minor B, the males occurred with T. boreoarcticus f. major and T. borearcticus f. minor A in endemic populations of muskoxen (Ovibos moschatus wardi) and barrenground caribou (Rangifer tarandus groenlandicus) on Victoria Island, Nunavut, Canada, and in muskoxen and Peary caribou (Rangifer tarandus pearyi) on Banks Island, Northwest Territories, Canada. These specimens differ from conspecific morphotypes in the structure of the genital cone and Sjöberg’s organ. Relative to T. boreoarcticus f. minor A, specimens of T. boreoarcticus f. minor B are consistently smaller, and mean dimensions for the bursa and spicules do not overlap. The robust spicules are similar in form, particularly in the relative length of the dorsal and ventral processes, but mean total length is substantially less in specimens of T. boreoarcticus f. minor B. Differences that distinguish the minor morphotypes of T. boreoarcticus parallel those demonstrated for the T. trifurcata and T. davtiani morphotypes in association with T. circumcincta sensu stricto. New host and geographic records include the three morphotypes of T. boreoarcticus in muskoxen and Peary caribou from Banks Island and in barrenground caribou from Victoria Island. Recognition of the ubiquitous nature of cryptic species emphasizes the need to effectively develop and use our collections-based resources and museum archives to build a robust understanding of the biosphere. Field inventory should include provisions for integrative approaches that preserve specimens suitable for comparative morphology, multifaceted molecular investigations, and population genetics

The Synlophe and Other Structural Characteristics of \u3ci\u3eSarwaria bubalis\u3c/i\u3e (Nematoda: Trichostrongyloidea) from Cattle in Guyana

The synlophe (longitudinal, surface cuticular ridges) of Sarwaria bubalis is described for the first time. It is a tapering lateral synlophe of about 40 ridges. The synlophe of S. bubalis is similar to that of Ostertagia ostertagi but markedly different from that of species of Spiculopteragia and Mazamastrongylus. New information is provided also on the structure of the esophagus and perivulval pores. The esophageal valve is more than twice as long as wide. The bilateral perivulval pores were located 192-267 μm posterior to the vulva and dorsal to the lateral lines. The new information will be useful in a study of the generic level systematics of the Ostertagiinae. Sarwaria bubalis appears to be well established in tropical South America where it infects its normal host, the Asian water buffalo Bubalus bubalis, as well as domestic cattle Bos taurus and mixed breed cattle B. taurus x Bos indicus

The Identification of Cattle Nematode Parasites Resistant to Multiple Classes of Anthelmintics in a Commercial Cattle Population in the US

Resistance to modern anthelmintics by ruminant nematode parasites is an increasing problem throughout the world. To date the problem has largely been reported in parasites of small ruminants, but there are increasing reports of such resistance in nematodes recovered from cattle. Until now there have been no published reports of drug resistant parasites from cattle in North America. In 2002 a producer in the upper Midwest who backgrounds young cattle acquired from the southeastern US experienced lower than expected weight gain as well as apparent parasitic gastroenteritis in his cattle during the fall. Fecal sample results supported the suspicion that decreased productivity and diarrhea were the result of GI nematode parasitism. The operation used intensive grazing management and practiced strategically timed deworming for \u3e17 years. In 2003, all animals were dewormed the first week of May with Ivomec Plus®, then with Dectomax® Injectable on 4 June and 17 July. On 31 July, 10 randomly taken fecal samples showed EPG values from 0 to 55. To assess whether the apparent decreased drug efficacy was the result of drug resistance in the nematode population, on 18 August approximately 150 heads, previously strategic timed dewormed, of 9–11 month old cattle from one pasture were selected for study. The calves were randomly assigned to 1 of 6 treatment groups: untreated (U), ivermectin injectable (I), moxidectin pour-on (M), doramectin injectable (D), eprinomectin pour-on (E), albendazole oral (A). Cattle were weighed prior to treatment and the drug was dosed according to label directions. Seven days later, 3 calves from each group were slaughtered for worm recovery. Fecal samples taken from the remaining animals at 14 days after treatment showed that the reduction of mean fecal EPG value for each group was: U-46%, I-52%, M-72%, D-61%, E-8%, and A-68%. Worm recovery from the slaughter calves showed that all groups harbored significant numbers of Haemonchus placei and H. contortus. In addition, all avermectin-treated groups contained significant numbers of Cooperia punctata, and smaller numbers of C. oncophora and C. spatulata. These results imply that the pastures studied contain substantial numbers of H. contortus resistant to both avermectins and benzimidazoles, and H. placei and Cooperia sp. resistant to all the commonly used avermectin anthelmintics. This is the first report of anthelmintic resistance in American cattle parasites

Redescriptions of \u3ci\u3eHaemonchus mitchelli\u3c/i\u3e and \u3ci\u3eHaemonchus okapiae\u3c/i\u3e (Nematoda: Trichostrongyloidea) and Description of a Unique Synlophe for the Haemonchinae

In the course of a revision of Haemonchus Cobb, 1898 (Nematoda), commonly referred to as large stomach worms, significant new morphological information was discovered that allows the recognition of two species believed for more than 50 years to be synonymous. Both species, Haemonchus mitchelli Le Roux, 1929, from the eland Taurotragus oryx and other African ruminants and H. okapiae van den Berghe, 1937, from the okapi Okapia johnstoni, have a synlophe of 42 ridges, but the synlophe of H. mitchelli is longer than that of H. okapiae. The distal tip of the left spicule of H. mitchelli bears a barb that is about twice as long as the short barb and half as long as the long barb on the right spicule. In contrast, the barb on the left spicule of H. okapiae is similar in size to the short barb and about 25% as long as the long barb of the right spicule. The dorsal ray of H. mitchelli is bifurcated distally for 25–39% (32%) of its length and its stem is expanded proximally, but the dorsal ray of H. okapiae is bifurcated 37-50% (42%) and its stem is of uniform thickness