Capillaria maseri sp. n. (Nematoda) from Insectivores (Soricidae and Talpidae) in Oregon

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1 OF WASHINGTON, VOLUME 40, NUMBER 1, JANUARY Phenomenes de convergence chez les spirurides, en particulier dans les sous-families Habronematinae Chitwood and Wehr, 1932 et Schistorophorinae L. Travassos, 1918; leur importance por tine classification naturelle des spirurides (Nematoda). Bull. Soc. Zool. Fr. 82: Inglis, W. G The nematodes parasitic in the gizzard of birds: A study in morphological convergence. J. Helminthol. 39: Mawson, P. M Habronematinae (Nematoda: Spiruridae) from Australian birds. Parasitology 58: Yeh, L. S On two new species of the genus Serticeps (Nematoda: Schistorophidae) from the gizzard of birds. J. Helminthol. 28: Capillaria maseri sp. n. (Nematoda) from Insectivores (Soricidae and Talpidae) in Oregon R. L. RAUSCH AND V. R. RAUSCH Arctic Health Research Center, Bureau of Community Environmental Management, Health Services and Mental Health Administration, Department of Health, Education, and Welfare, Fairbanks, Alaska ABSTRACT: Capillaria maseri sp. n. is described from the urinary bladder of shrews, Sorex spp. (type host: S. yaquinae Jackson) in Oregon, and is recorded also from the shrew-mole, Neiirotrichus gibbsii (Baird). C. maseri is the first capillariid to be reported from the urinary bladder of North American insectivores. In , nematodes of the genus Capillaria Zeder, 1800, were found in the urinary bladder of insectivores collected in Oregon by Chris and Rita Maser, Oregon Coast Ecological Survey, Puget Sound Museum of Natural History, who kindly sent the specimens to us for study. The species involved differs from any recorded from insectivores in Eurasia and North America and is described herein. Materials and Methods Most of the specimens had been fixed in situ in 10% formalin solution. Fifty-six were studied in detail, including some that were broken in dissecting the anterior ends from tissue of the urinary bladder. They were cleared by evaporation of a mixture of 2% glycerin in 70% ethanol, after which selected specimens were stained in light green SF dissolved in glycerin. Two bladders with nematodes in situ were embedded in paraffin, sectioned at or mm, and stained in hematoxylin-eosin, in Mallory's aniline blue collagen stain, or by the periodic acid-schiff reaction. For comparison, sections were similarly prepared from the normal urinary bladder of a shrew collected in Alaska. The hosts were identified by Mr. Maser. The nomenclature of shrews is in accordance with the recommendations of Johnson and Ostenson (1959). Results Description Numbers of specimens from which the respective measurements were derived are shown in parentheses. All measurements are in millimeters. Capillaria maseri sp. n. (Figs. 1-8) Slender nematodes; white in color when preserved. Bacillary lines present. Mouth simple. Cuticle smooth. MALE (23 specimens; 8 intact): Length (8) 7.3 to 20.5 (avg 17.1). Maximum width (22) to (avg 0.123), attained in posterior third of body. Width at cephalic extremity (8) to (avg 0.010); width at posterior extremity (23) to

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3 OF WASHINGTON, VOLUME 40, NUMBER 1, JANUARY (avg 0.032). Esophagus (8) 3.7 to 7.9 long (avg 6.5); width at base (19) to (avg 0.056). Length of muscular esophagus (4) to (avg 0.375). Ratio of length of esophagus to length of body (8) 1:1.9 to 1:3.1 (avg 1:2.6). Twenty-six to 48 esophageal cells observed. Distance from posterior end of esophagus to testis (19) to (avg 0.645). Length of spicule (23) to (avg 0.970). Spicule sheath aspinose, with minute folds. Caudal alae not present. FEMALE (33 specimens; 10 intact): Length (10) 7.7 to 26.8 (avg 18.4). Maximum width (32) to (avg 0.145), attained in posterior third of body (containing uterus). Width at cephalic extremity (7) to (avg 0.010). Width at posterior extremity (33) to (avg 0.044). Width at level of vulva (30) to (avg 0.092). Esophagus (10) 2.93 to 10.4 (avg 7.5) long; width at base (28) to (avg 0.062). Length of muscular esophagus (5) to (avg ). Thirtynine to 41 esophageal cells observed. Ratio of length of esophagus to length of body (10) 1:1.6 to 1:2.9 (avg 1:2.5). Nerve ring (5) ca from anterior end. Distance from posterior end of esophagus to vulva (28) to (avg 1.145). Distance from cephalic extremity to vulva (9) 3.5 to 11.4 (avg 9.0). Anus terminal. Egg (178) to by to (avg by 0.028); shell smooth; polar plugs well defined. TYPE HOST: Sorex yaquinae Jackson. Other hosts S. vagrans Baird, S. bendirii (Merriam), S. trowbridgii Baird, S. pacificus Coues, and Neiirotrichus gibbsii (Baird). TYPE LOCALITY: Cascade Head Experimental Forest, Lincoln County, Oregon. HABITAT: Urinary bladder. TYPES: USNM Helm. Coll. No holotype (male) and No allotype; Nos and (paratypes). Discussion With the exception of C. hepatica (Bancroft, 1893), which has been reported from mammals of diverse groups, species of Capillaria from mammals are usually host-specific. That certain species have been found in hosts representing two or more related families indicates that their occurrence may be influenced by ecologic, as well as phylogenetic, factors. Such is the case with C. maseri, occurring in both shrews (Soricidae) and moles (Talpidae). However, in any host infected, the respective species appear to be organ-specific. In Eurasia, nematodes of the genus Capillaria have been found in the urinary bladder of moles and shrews, but none has been reported from this organ in North American insectivores. The two species known from insectivores in North America, C. rauschi Read, 1949, and C. blarinae Ogren, 1953, were described from the small intestine of Sorex cinereus Kerr and the esophagus of Blarina brevicauda (Say), respectively. Wakelin (1968) suggested that C. rauschi is possibly identical with C. kutori Rukhliadeva, 1946, described from the stomach of water shrews, Neomys fodiens (Pennant), from the Khopersk Reserve, European Russia. His hypothesis, if valid, would add another species of the genus Capillaria from mammals to those few known to be holarctic, of which none is from insectivores. It seems improbable, on zoogeographic grounds, that the two are conspecific; unfortunately, a conclusion cannot be made from the descriptions of C. kutori (Rukhliadeva, 1946; Soltys, 1954). C. kutori appears to be a common parasite of shrews in eastern Europe (Prokopic, 1959; Arzamasov et al., 1969), and it was identified by Wakelin (1968) from the intestine of Sorex araneus L. in England. Comparisons A distinctive morphological characteristic of C. maseri is the relatively great distance between the end of the esophagus and the vulva Figures 1-8. Capillaria maseri sp. n. 1. Anterior end of female. 2. En face view of cephalic end of male, slightly oblique. 3. Posterior end of male. 4. Caudal extremity of male, with partially everted spicule. 5. Terminal portion of esophagus, female. 6. Details of vulva and associated structures. 7. Caudal extremity of female. 8. Structure of egg.

4 110 PROCEEDINGS OF THE HELMINTHOLOGICAL SOCIETY O.I mm,, Figure 9. Section of wall of bladder (Sorex yaquinae) showing anterior ends of C. maseri embedded in the mucosa. PAS stain, mm section. (avg mm). C. maseri differs from the two species previously described from North American shrews in other characters as well as in habitat. From C. rauschi, it is distinguished by the presence of bacillary lines, smooth cuticle, different position of the vulva, and smooth-shelled eggs of larger size; from C. blarinae by the larger size, longer esophagus, longer spicule, absence of spines in spicule sheath, and, in females, by the presence of an external vulvar process and a terminal anal opening. Several species of Capillaria occurring in the urinary bladder of insectivores have been described in Eurasia. C. capillaris (von Linstow, 1882) and C. incrassata (Diesing, 1851) have been recorded from both moles and shrews. Wakelin (1968) concluded that C. capillaris could be synonymized with C. incrassata, a determination that was not accepted by Prokopic and Mahnert (1970) or Nadtochii and Rasskazova (1971). Both species have been found in western Eurasia as well as in Kamchatka, in northeastern Siberia (Nadtochii and Rasskazova, 1971). C. urinicola Soltys, 1952, described from shrews in Poland, was later considered by Soltys (1954) to be identical with C. capillaris. However, comparisons by Furmaga (1959) led to the conclusion that C. urinicola is distinct. The similarity between C. sunci Chen,.1.937, described from Suncus caeruleus (= S. murinus L.) (Soricidae) in China, and C. incrassata was recognized by Lopez-Neyra (1947, p. 140). Wakelin (1968, p. 392) stated that this species "... may well be considered a synonym of C. incrassata." C. reni Shaldybin, 1968, described from water shrews from the Mordovsk Reserve in European Russia, might also be considered here, although it was found in the renal pelvis rather than in the urinary bladder.

5 OF WASHINGTON, VOLUME 40, NUMBER 1, JANUARY C. maseri may be distinguished as follows from these other species inhabiting the urinary system of insectivores: from C. capillaris by its larger size, longer esophagus, vulva situated farther posteriorly, and smooth-shelled egg; from C. incrassata by its larger size, more slender anterior end, smooth cuticle, and longer spicule; from C. urinicola by its larger size, longer esophagus, presence of vulvar process, and a much larger egg; from C. reni, of similar large size, by its longer spicule and, in the female, by its terminal anal opening and smaller egg. The description of C. reni does not permit comparison of other anatomical details. Parasite-host relationships C. maseri occurred in 43 (31%) of 138 shrews collected during November 1970-April It was found also in one of seven shrewmoles, Neurotrichus gibbsii, but in none of 16 Townsend's moles, Scapanus townsendii (Bachman), or in 17 coast moles, S. orarius True. In 32 infected shrews, not segregated by species, numbers of nematodes ranged from 1 to 29, with an average of 4. The ratio of males to females in this series was 1:1.7. Five specimens were found in the bladder of the shrewmole. Findings in mammals of the respective species are summarized in Table 1. Mammals of both sexes were infected. The nematodes formed localized aggregations on the floor of the urinary bladder in the vicinity of the neck, with the anterior portion of their bodies deeply embedded in the mucosa. Males penetrated to the full length of the esophagus, females to the level of the vulva, permitting discharge of eggs directly into the lumen of the bladder. In sections of incised, contracted bladders, in which the mucosa was thrown into deep, irregular folds, the anterior portions of the nematodes extended erratically through the thick epithelial layer, but not penetrating the connective tissue of the lamina propria, nor did they pass through the mucosa into the underlying muscularis (Fig. 9). No observations were made on relationships in the distended bladder, in which the respective layers of tissue would be much flattened. Findings in tissue sections indicate that C. maseri is not pathogenic in shrews. The embedded portions of the nematodes were im- Table 1. Occurrence of C. maseri in shrews and moles. Host Soricidae Sorex va grans S. pacificus S. i/aquinae S. bendirii S. trowbrtdgii Talpidae Neurotrichus gibbsii Scapanus orarius S'. townsendii No. examined No. infected mediately surrounded by normal-appearing epithelial cells; leukocytic infiltration, fibrosis, or other evidence of an inflammatory response were not observed. No eggs were found within the tissue of the host. The tissue reaction, if any, evoked by other species of Capittaria inhabiting the urinary bladder of insectivores apparently has not been described. A slide with sections of the nematode in situ has been deposited in the USNM Helm. Coll., No No early-stage infections involving newly established nematodes were detected, although a few immature specimens were found. In the shrew-mole, one of the nematodes was within the ureter; however, migration from the bladder might have taken place after the death of the host. Most of the insectivores were captured along the coast of Oregon in the vegetational zone characterized by Sitka spruce, a region of low elevation, mild climate, and high annual precipitation (Franklin and Dyrness, 1969). Of the five species of shrews involved, S. trowbridgii, S. pacificus, and S. yaquinae inhabit forest and are nocturnal. S. bendirii is found near water, while S. vagrans inhabits meadows as well as grassy areas along streams; both are active at any time of day. During the drier months (summer and autumn), all but S. vagrans were usually trapped within 25 m of streams. The shrew-mole has shrewlike habits; it usually occurs in forest and is active at any time of day. The infected insectivores were trapped in moist habitat in serai vegetation. C. maseri was found also in a single specimen of S. bendirii from the western foothills of the Cascade Range (Lane County), at an elevation of about 1,000 m. (The foregoing data were provided by C. Maser.) Seasonal differences in rates of infection in 1 1_ -

6 112 PROCEEDINGS OF THE HELMINTHOLOGICAL SOCIETY shrews could not be discerned. Infected animals were obtained during all months but September and October. The lowest annual rates would be expected in autumn, when the populations of shrews consist predominantly of young animals. Acknowledgments We express thanks to Mr. and Mrs. Chris Maser, who provided the material studied as well as a record of their field observations, and to Dr. B. Horning, Vet.-Bakteriologisches und Parasitologisches Institut, Universitat Bern, Switzerland, who provided the otherwise unavailable description of C. rent. Literature Cited Arzamasov, I. T., I. V. Merkusheva, O. N. Mikholap, and I. V. Chikilevskaia Nasekomoiadnye i ikh parazity na territorii Belorussii. Nauka i Tekhnika, Minsk, 175 p. Franklin, J. F., and C. T. Dyrness Vegetation of Oregon and Washington. US- DA Forest Service Res. Paper PNW-80, Portland, Oregon, 216 p. Furmaga, S Internal parasites of the mole (Talpa europaea L.) in the Lublin environment. Acta Parasit. Polon. 7: Johnson, M. L., and B. T. Ostenson Comments on the nomenclature of some mammals of the Pacific Northwest. J. Mammal. 40: Lopez-Neyra, C. R Los Capillarinae. Mem. Real Acad. de Ciencias, Ser. Ciencias Nat., Madrid 12: Nadtochii, E. V., and T. T. Rasskazova Nematody zemleroek nekotorykh territorii Dal'nego Vostoka. In E. V. Gvozdev (ed.), Biologicheskie Problemy Severa, p Trudy Severo-vostochnogo Komplekskogo Inst., Akad. Nauk SSSR, Magadan, 239 p. Prokopic, J Cizopasni cervi nasich hmyzozravcu. Systematicko-faunisticka studie a ekologicko-zoogeograficke zhodnoceni. Cesk. Parasit. 6: , and V. Mahnert Uber Helminthen der Kleinsauger (Insectivora, Rodentia) Tirols (Osterreichs). Ber. Nat.-Med. Ver. Innsbruck 58: Rukhliadeva, M. N K izucheniiu nematod roda Capillaria Zeder, 1800, ot kutory (Neomys fodiens Pall.). In V. P. Pod'iapol'- skaia (ed.), Gel'mintologicheskii Sbornik, p Akad. Nauk SSSR, Moscow-Leningrad, 302 p. Soltys, A Helminthofauna of Soricidae in the Bialowieza National Park. Acta Parasit. Polon. 1: Wakelin, D Nematodes of the genus Capillaria Zeder, 1800 from the collection of the London School of Hygiene and Tropical Medicine. III. Capillariids from mammalian hosts. J. Helminthol. 42: A New Subfamily, Two New Genera, and Three New Species of Haploporid Trematodes1 W. E. MARTIN Department of Biological Sciences, University of Southern California, Los Angeles, California ABSTRACT: A new subfamily, Unisaccinae, of the family Haploporidae is established to include the new genus Unisaccus and the new species, U. brisbanensis and U. spinosus; and the new genus and species Unisaccoides vitellosus found in the intestines of mullet in the Brisbane River, Queensland, Australia. These worms are unique among haploporids in having a single cecum. During sabbatical leave ( ) spent in the Parasitology Department, University of Queensland, Brisbane, Australia, Brisbane River mullet were found to harbor in their small 1 Supported by NSF G6962. intestines some trematodes that are unique among haploporids in the possession of an undivided cecum. They are described as two new genera and three new species of a new subfamily.