Gregson, J. D.

English

Journal of the Entomological Society of British Columbia

ENTOMOLOGICAJ, Soc. OF BRITISH COLUMBIA, PROC. (1948), VOL. 45, JULY 28, 1949 15 NOTES ON THE OCCURRENCE OF O'RNITHODO,ROS HERMSI IN BRITISH COLUMBIA, AND ITS PROBABLE RELATIO'N TO RELAPSING FEVER. ARGAS,IDAE, IXODOIDEA.'~ J. D. GREGSON Livestock Insects Laboratory, Kamloops, B.C. A new distributional and host record has been established by' the recent discov-ery of the soft tick Ornithodoros hermsi Wheeler, Herms and Meyer, at Summer-land, British Columbia. Two engorged adult specimens of the tick were forward-ed to the Dominion Livestock Insect Lab-oratory at Kamloops on August 4th, 1948, by Mr. C. V. G. Morgan of the Domin-ion Fruit Insect Laboratory, Summerland, who, in turn, had received them from a local resident. This person had been bit-ten some dozen times in bed since April by nocturnal creatures which she believed to be bedbugs. Finally she captured two of the culprits and opened the way for this interesting discovery. Investigation by the writer revealed her residence to be an old building situated in an orchard on a West Summerland bench-land. The occupant and her mother kept no animals and knew of no rodents being present, with the exception of a packrat that had visited her basement the previous fall, and a mouse that she had caught there recently. There was, however, a bluebird nest in an old woodpecker hole in the eaves over an upper verandah. This was examined, and yielded, besides five fledgling bluebirds, a large number of avian bedbugs, Oeciacus v,icarius Rorv., and twenty-six specimens of Ornithodoros hermsi. The ma~ority of the ticks had re-cently fed, and were found in the main nesting material. Since this was without doubt the source of the infestation it is of interest to note that the initial specimens captured had migrated over a distance of two storeys, including accents up wooden and steel bed legs. After the contents of the nest were removed, the enclosure * Contribution No. 2575, Division of Entomology, Science Service, Department of Agriculture, Ottawa, Canada. was sprayed with DDT and sealed. How-ever, it is expected that the occasional specimen may still appear in crevices in the well kept but old residence. To date, sev-eral feedings on laboratory mice have failed to reveal spirochetes. The human bites produced no effects other than a se-vere and prolonged local reaction. This tick record bears two points of considerable interest. Firstly, the biotope records of O. hermsi) as sta~ed by Cooley and Kohls, (1935), consist of chipmunk nests in either fir snags, stumps or hollow logs or cabins, but never ground burrows. These observations, together with the marked localization of observed in festa-tions would suggest a possibility that the tick is primarily spread and maintained by an avian host. Secondly, thi~ species is known to bite man, and because of known cases of relapsing fever originating from in~ested areas, with subsequent isolation of spirochetes from specimens captured there, it has been proven a vector of this disease in California, Colorado, Nevada, Oregon, northern Idaho and Washington (Davis 1942, 1945). In 1930 and 1932 there occurred a series of six human cases of relapsing fever in the Kootenay District of British Columbia, (Palmer and Crawford 1933). Considerable speculation arose as to what the vector could be. Rearle (1934) advanced the theory that one of the Argasid ticks must be involved, though a careful search by staff members of this laboratory failed to find any indications of these parasites. Again, in 1937 this laboratory was informed by Dr. Campbell Brown of Vernon, British Columbia, that two loggers from Okanagan Centre had been suffering from a series of relapses. A further search for vectors once more proved futile. Thus it is seen that an Argasid tick has long been suspected as oc-16 ESTOMOLOGlCAL Soc. OF BKITl:;U COI.L\WL\. PH()('. (1948), VOL. 45, JULY 28, 1949 cUIT ing in British Columbia, and as point-ed Ollt hy Da vis (1945), th e presence of O. herm si in the contiguous a reas o f nor-th ern Idaho and eastern W ashin g ton sug-gested that this species may have been re-sponsihl e for the above cases. While at-tempts to fin d it had fa il ed, the search had been directed only to wa rd s rodent hosts and gwund hurrows. The final discove ry of O. hCI'IlI si in a bird's nest in the prov-ince consequ ently throws an interesting light on th e whol e picture. LITE RAT U RE CITED Cooley, R. A., and G. M. Kohls, 1935. The Argasidae of North America, Cent ral America and Cuba. The ArneI', Midla nd Nat. Monograph No. 1.. U . of Notre D.lme, pp.I-152; tex t figs. 1-57; plates 1-14. Davis, G. E., 1942. Tick Vectors a nd Life Cycles of Ticks. A.A.A.S. Monograph No. 18, pp. 67-76. Davis, G. E., 1945. In Mackie, T . T. , Hunter, G . W .. and C. B. Wor th , M anual Trop. Med., Saunders. Hearle, E., 1934. Vectors of R elapsing F ever in Relation to a n Outbreak of the Disease in British Columbia. Can. Med . Assoc . Journ. 30:494-497. Palmer, J. H., and .l. M. Crawford, 1933. Relapsing Fever in North America with Report of an Outbreak in British Columbia. Can. Med. Assoc. Journ . 28:643-647. PARASITIC COLEOPTERA GEO. R. HOPPING University of British Columbia, Vaneou vel', B.C. P aras itism in th e Coleoptera is so rare that whcn a parasitic species is di scove red it is an event of considerable n ote. There are fi ve known species of hec tl cs pa rasitic, or suspected of being parasiti c on birds and m ammal s. The collection o f th e UniYer-sit)' of British Columhia conta ins four of thesc spec ies whic h is ra th er re m arka ble an d a trihute to Pm fesso r G. J. Spence r w ho has persistently and ass iduously built up this collection. The spec ies of parasi tic C o lcopte ra rep-resen t three families and four gen era in th e super-family Staphy Linoirica. T h c family Pl(/typsillir/(/c contains onc species only, Platypsy/lw castoris Ritse m a. This curious insec t has been known since 1869 and has bee n ta ken a conside rahle numher of t im es both ill Europe alld Am l' rica, on beave r, where it is a permanent, obliga te paras itc. The head o f the adult is pro vided w ith a comb- like row of spines nea r th e h ind ma rg in. There are no eyes, and th e man-dihles a re vestigial. The m axillae a re well del'c loped and arc similar to th ose of oth-er Coleoptera. This insec t was placed in a separa te order hI' \Vl's tw()od, hut th e larva l cha racters are unmistakab ly coleop-terollS Its place within th e order is Somc-what in do uht. A ca reful, morphologica l study of al l sta ges mig ht yield a perman -(,nt so lution to the prohlem. In th e fa mily L cptinida(, therc are two genera and th rce spec ies. Leptinlls tcst(l-COIS .'V1ull., oftcn has heen recorded from the n est of humhl e bees and once has been reco rd ed as occu rrin g on mice and once ['-'>111 shrews. Y)ore rl'ce ntl y J. D. Greg-son took it O il a spec ies o f S orcx from Sil-\u Cree k, B.C., i\pril 26, 1940. This species if co rrectly determined, is about 2.5 111m. long, reddis h brown in colour, with 11 s ~'~1l1('n t c d antennae and 5 se~­menteci tarsi.Thnc a re 6 visible ahdomin: l! sC'gments. Th e entire body is covered with ,;ilOrt seta e, sparse ly ;lllc! uniformly distri-buted. Th e m ou th parts were difficult to distin g uish but obv io usly th e max illae arc well developed w hil e the mandibles ap-pea r to bc vest ig ial and th e eyes arc want-ing . Th e fr" nt coxae are conti g uous, th e intercoxa l pi ece ilcu m inate. The elytra complete!.\· or nca r!.\' cove r the abdomen, and there a rc no hind wings. The ge lllls Ltptinillm is represented hy two species, L. v(/LidliS Horn ilnd L. aplo'-r/rmtial' Ferris. Th e former species was desc ribed in 11li2 an d has heen recorded from A la';/';:a n heave r skin s by C . V. Riley 

Notes on the occurrence of Ornithodoros hermsi in British Columbia, and its probably relation to relapsing fever (Argasidae: Ixodoidea)

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Notes on the occurrence of Ornithodoros hermsi in British Columbia, and its probably relation to relapsing fever (Argasidae: Ixodoidea)

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