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Helminths of Six Species of Colubrid Snakes from Southern California.
Subject:
Snakes (Health aspects)
Helminths (Research)
Parasites (Research)
Authors:
Goldberg, Stephen R.
Bursey, Charles R.
Pub Date:
08/01/2001
Publication:
Name: Bulletin (Southern California Academy of Sciences) Publisher: Southern California Academy of Sciences Audience: Academic Format: Magazine/Journal Subject: Science and technology Copyright: COPYRIGHT 2001 Southern California Academy of Sciences ISSN: 0038-3872
Issue:
Date: August, 2001 Source Volume: 100 Source Issue: 2
Geographic:
Geographic Scope: California Geographic Name: California Geographic Code: 1U9CA California

Accession Number:
78974793
Full Text:
Stephen R. Goldberg [1]

Charles R. Bursey [2]

Abstract.--Six species of colubrid snakes from California were examined for helminths: Arizona elegans, Chionactis occipitalis, Masticophis flagellum, Masticophis lateralis, Phyllorhynchus decurtatus and Rhinocheilus lecontei. One species of Trematoda, Paralechriorchis syntomentera, two species of Cestoda, Oochoristica osheroffi and Mesocestoides sp. (tetrathyridia), four species of Nematoda, Physaloptera abjecta, Spauligodon goldbergi, Thubunaea iguanae, and Physaloptera sp. (larvae) and one species of Acanthocephala represented by cystacanths (Oligacanthorhynchidae), were found. Nine new host records are reported.

Although 38 species of snakes are recorded for California (Brown 1997), few have been examined for helminths. There are reports of helminths for Crotalus cerastes, C. ruber, C. viridis, Rhinocheilus lecontei, and Thamnophis elegans collected in California (Voge 1953; Alexander and Alexander 1957; Mankau and Widmer 1977; Widmer and Specht 1992; Bursey et al. 1995; Goldberg et al. 1998). The purpose of this study was to examine 6 species of colubrid snakes from California for helminths: the glossy snake, Arizona elegans; western shovelnose snake, Chionactis occipitalis; coachwhip, Masticophis flagellum; striped racer, Masticophis lateralis; spotted leafnose snake, Phyllorhynchus decurtatus; and longnose snake, Rhinocheilus lecontei. Geographic ranges for these snakes are in Stebbins (1985). Of these 6 species, only Masticophis flagellum (from Georgia, Texas) has been examined for helminths (Harwood 1932; Reiber et al. 1940; Schad 1962; Conn and McAllister 1990).

Materials and Methods

One hundred fifty-nine individuals of six colubrid snake species: Arizona elegans (n = 43, mean snout-vent length [SVL] = 589 mm [+ or -] 205 SD, range = 238-930 mm), Chionactis occipitalis (n = 31, SVL = 258 mm [+ or -] 20 SD, range = 222-300 mm), Masticophis flagellum (n = 12, SVL = 861 mm [+ or -] 118 SD, range 697-1104 mm), Masticophis lateralis (n = 14, SVL = 765 mm [+ or 1] 136 SD, range 520-963 mm), Phyllorhynchus decurtatus (n = 26, SVL = 357 mm [+ or -]47 SD, range = 242-469 mm), and Rhinocheilus lecontei (n = 33, SVL = 590 mm [+ or -] 93 SD, range = 362-743 mm) were borrowed from the herpetology collection of the Natural History Museum of Los Angeles County (LACM), Los Angeles, California (accession numbers, Appendix 1). Eleven of 14 Masticop his lateralis (79%) were from the San Gabriel Mountains (34[degrees]18'N, 117[degrees]50'W) Los Angeles County, 3 (21%) were from the Puente Hills (34[degrees]01'N, 117[degrees]57'W) Los Angeles County, California. All individuals of the other five species were from desert areas in the Coachella Valley (33[degrees]50'N, 116[degrees]20'W) of Riverside County, California. Snakes were collected from 1951 to 1975.

The body cavity was opened by a longitudinal incision from vent to throat and the gastrointestinal tract was excised by cutting across the esophagus and rectum. The esophagus, stomach, and small and large intestines were slit longitudinally and examined under a dissecting microscope. Nematodes were examined and identified after clearing in a drop of concentrated glycerol. Trematodes, cestodes and acanthocephalans were regressively stained in hematoxylin and studied as whole-mounts in Canada balsam. Voucher helminths were deposited in the United States National Parasite Collection, (USNPC) Beltsville, Maryland (Appendix 2).

Results

One species of Trematoda, Paralechriorchis syntomentera (Sumwalt 1926) Bryd and Denton 1938; two species of Cestoda, Oochoristica osheroffi Meggitt 1934 and Mesocestoides sp. (as tetrathyridia); four species of Nematoda, Physaloptera abjecta Leidy 1856, Spauligodon goidbergi Bursey and McAllister 1996, Thubunea iguanae Telford 1965, Physaloptera sp. (third stage larvae); and one species of Acanthocephala represented by oligacanthorhynchid (proboscis short, globular; hooks in six spiral rows) cystacanths were found. Number of helminths, prevalence (infected snakes of a species divided by snake sample size expressed as a percentage), mean intensity (mean number of helminths per infected snake) and infection sites within the host are given in Table 1. Nine new host records are reported. Arizona elegans and Masticophis lateralis harbored five helminth species each; Chionactis occipitalis and Rhinocheilus lecontei harbored three; Masticophis flagellum harbored two and Phyllorhynchus decurtatus harbored one helmin th species. Helminth community characteristics are given in Table 2.

Discussion

Arizona elegans, Chionactis occipitalis, Masticophis flagellum, Phyllorhynchus decurtatus and Rhinocheilus lecontei are sympatric in southern California and are found in dry, relatively open areas supporting chaparral, creosote bush, mesquite and sagebrush (Behler and King 1979). Masticophis lateralis prefers chaparral, open hardwood-pine forest in the mountains and is especially common around water (Behler and King 1979).

All helminths found in this study have been previously reported from snakes. Paralechriorchis syntomentera was originally described as Zeugorchis syntomentera by Sumwalt (1926) from the mouth cavity of Thamnophis sirtalis collected on San Juan Island, San Juan County, Washington. Byrd and Denton (1938) erected the genus Paralechriorchis for it and two closely related species. The life history of P. syntomentera was described by Ingles (1933) who experimentally infected young Thamnophis ordinoides collected at Berkeley, Alameda County, California through the ingestion of infected amphibians. Fantham and Porter (1954) have also reported Thamnophis ordinoides of Quebec, Canada to harbor P. syntomentera. Masticophis lateralis is a new host record.

Qochoristica osheroffi was originally described from Pituophis melanoleucus collected in Nebraska by Meggitt (1934). Alexander and Alexander (1957) described Oochoristica crotalicola from Crotalus cerastes and C. viridis of California; however, this cestode was synonymised with O. osheroffi by Widmer (1966). Oochoristica osheroffi has been reported in Crotalus viridis from Colorado and New Mexico (Widmer and Olsen 1967; Pfaffenberger et al. 1989). Arizona elegans and Masticophis lateralis represent new host records.

Tetrathyridia of Mesocestoides sp. are frequently found in snakes; McAllister et al. (1991) have summarized world occurrences. Tetrathyridia have been previously found in Masticophis flagellum from Texas by Conn and McAllister (1990) and from Crotalus atrox, C. lepidus, C. molossus, C. pricei, C. ruber, C. scutulatus, C. tigris, C. viridis and Thamnophis elegans from California (Voge 1953; Mankau and Widmer 1977; Widmer and Specht 1992; Bolette 1997a, 1997b; Goldberg and Bursey 1999). This is the first report of tetrathyridia in Arizona elegans, Masticophis lateralis and Rhinocheilus lecontei. Bolette (1 997a) believed rattlesnakes serve as paratenic hosts.

Physaloptera abjecta was originally described from Masticophis flagellum (= Psammophis flagelliformis) from Pennsylvania by Leidy (1856). The identity of this snake is uncertain as M. flagellum does not occur in Pennsylvania (Conant and Collins 1998). Physaloptera variegata Reiber, Byrd and Parker 1940, described from a Coluber constrictor collected in Florida, was synonymized with P. abjecta by Morgan (1941). It has been reported from Masticophis flagellum of Georgia (Reiber et al. 1940) as well as the colubrids Coluber constrictor, Heterodon platirhinos, Lampropeltis getula, Opheodrys (= Liopeltis) vernalis and Thamnophis sirtalis from Georgia, Florida or Wisconsin and the anguid lizard, Ophisaurus ventralis from Georgia (Reiber et al. 1940; Morgan 1941; Mawson 1956). Arizona elegans is a new host record; California is a new locality record.

Spauligodon goldbergi was described from the ground snake, Sonora semiannulata, from Texas by Bursey and McAllister (1996). This is the second report of Spauligodon goldhergi. Chionactis occipitalis represents a new host record; California is a new locality record.

Thubunaea iguanae was originally described from the phrynosomatid lizard, Sceloporus magister, from Riverside County, California and was present in a variety of lizards collected by Telford (1965). Arizona elegans, Chionactis occipitalis, Masticophis flagellum and Rhinocheilus lecontei represent new host records. A related species, Thubunaea cnemidophorus, has been reported from Crotalus cerastes, C. mitchellii and C. scutulatus of southern Nevada (Babero and Emmerson 1974).

Third stage larvae of Physaloptera sp. were present in each of the species examined in this study and have also been reported in M. flagellum from Texas by Conn and McAllister (1990). The majority of the 16 species of Physaloptera from North America listed by Morgan (1941) have mammalian hosts. All species of Physaloptera require an insect intermediate host (Anderson 2000) and could be expected in any insectivore. Amphibians and reptiles harboring larvae of Physaloptera sp. but no adults are summarized in Goldberg et al. (1993). Because these larvae were found mainly in the intestine of the snakes examined, we believe they are a by-product of diet and will be passed in feces without further development. This is the first report of physalopteran larvae in A. elegans, C. occipitalis, M. lateralis, P. decurtatus and R. lecontei.

Oligacanthorhynchid cystacanths of acanthocephalans have previously been reported in Rhinocheilus lecontei from Riverside County, California as well as Arizona, Texas and Mexico (Goldberg et al. 1998). In addition, Bolette (1997b) reported oligacanthorhynchid cystacanths in Rhinocheilus lecontei collected in Arizona and provided a list of cystacanths from nine additional snake species. This is the first report of cystacanths in Masticophis lateralis.

The helminths found in this study fall into two categories: those requiring intermediate hosts, namely Paralechriorchis syntomentera, Oochoristica osheroffi, Physaloptera abjecta, Thubunaea iguanae, and the acanthocephalans; and those infecting directly by egg ingestion, namely Mesocestoides sp. and Spauligodon goldbergi. In all cases, it is an oral route of infection.

There is some dietary overlap in these snakes: Arizona elegans feeds mainly on lizards and rodents with a few birds and snakes; Chionactis occipitalis eats insects, spiders, scorpions and centipedes; Masticophis flagellum feeds on small mammals, birds, lizards, snakes, insects and carrion; Masticophis lateralis eats frogs, lizards, snakes, small mammals, birds and insects; Phyllorhynchus decurtatus feeds on small lizards and their eggs; Rhinocheilus lecontei feeds almost exclusively on lizards (Stebbins 1985; Rodriguez-Robles et al. 1999). Widmer and Olsen (1967) suggested that helminth infections can be transmitted to snakes when snakes eat infected arthropods or when they eat prey which has recently fed on infected arthropods. Likewise, ingestion of prey infected by a species of Mesocestoides or by Spauligodon goldbergi could introduce feces containing eggs of these species into a snake host with subsequent development of an infection.

Examination of other California snakes will be needed before helminth communities can be described and assigned. However, it is of interest to note that only Masticophis lateralis which is especially common in areas with water (Behler and King 1979) harbored Paralechriorchis syntomentera, a helminth requiring amphibians as intermediate hosts. All sympatric desert snakes eating lizards harbored Thubunaea iguanae. All six species contained third-stage larvae of Physaloptera sp., more likely a by-product of diet than potential infection. One desert snake species, Arizona elegans, and the non-desert species, Masticophis lateralis, harbored Oochoristica osheroffi, typically a parasite of rattlesnakes.

Acknowledgments

We thank David A. Kizirian (Natural History Museum of Los Angeles County) for permission to examine snakes and Cheryl Wong and Megan E. Lahti for assistance with dissections.

(1.) Department of Biology, Whittier College, Whittier, California 90608

(2.) Department of Biology, Pennsylvania State University, Shenango Campus, Sharon, Pennsylvania 16146

Literature Cited

Alexander, C. G., and E. P. Alexander. 1957. Oochoristica crotalicola, a new anoplocephalid cestode from California rattlesnakes. J. Parasitol. 43:365-366.

Anderson, R. C. 2000. Nematode parasites of vertebrates: Their development and transmission., 2nd edition, CABI Publishing, CAB International, Wallingford, Oxon, United Kingdom, xx + 650 pp.

Babero, B. B., and F. H. Emmerson. 1974. Thubunaea cnemidophours in Nevada rattlesnakes. J. Parasitol. 60:595.

Behler, J. L., and F. W. King. 1979. The Audubon Society field guide to North American reptiles and amphibians. Alfred A. Knopf, New York, 743 pp.

Bolette, D. P 1997a. First record of Pachysentis canicola (Acanthocephala: Oligacanthorhynchida) and the occurrence of Mesocestoides sp. Tetrathyridia (Cestoidea: Cyclophyllidea) in the western diamondback rattlesnake, Crotalus atrox (Serpentes: Viperidae). J. Parasitol. 83:751-752.

-----. 1997b. Oligacanthorhynchid cystacanths (Acanthocephala) in a long-nosed snake, Rhinocheilus lecontei lecontei (Colubridae) and a Mojave rattlesnake, Crotalus scutulatus scutulatus (Viperidae) from Maricopa County, Arizona. Southwest. Nat. 42:232-236.

Brown, P. R. 1997. A field guide to snakes of California. Gulf Publishing Company, Houston, Texas, viii + 215 pp.

Bursey, C. R., S. R. Goldberg, and S. M. Secor. 1995. Hexametra boddaertii (Nematoda: Ascaridae) in the sidewinder, Crotalus cerastes (Crotalidae), from California. J. Helm. Soc. Wash. 62:78-80.

Bursey, C. R., and C. T. McAllister. 1996. Spauligodon goldbergi sp. n. (Nematoda: Pharyngodonidae) and other parasites of Sonora semiannulata (Serpentes: Colubridae) from New Mexico and Texas. J. Helm. Soc. Wash. 63:62-65.

Byrd, E. E., and J. F. Denton. 1938. New trematodes of the subfamily Reniferinae, with a discussion of the systematics of the genera and species assigned to the subfamily group. J. Parasitol. 24:379-401.

Conant, R., and J. T. Collins. 1998. A field guide to reptiles and amphibians: Eastern and central North America, third edition, Houghton Mifflin Company, Boston, xviii + 616 pp.

Conn, D. B., and C. T. McAllister. 1990. An aberrant acephalic metacestode and other parasites of Masticophis flagellum (Reptilia: Serpentes) from Texas. J. Helminthol. Soc. Wash. 57:140-145.

Fantham, H. B., and A. Porter. 1954. The endoparasites of some North American snakes and their effects on the Ophidia. Proc. Zool. Soc. London 123:867-898.

Goldberg, S. R., and C. R. Bursey. 1999. Crotalus lepidus (Rock Rattlesnake), Crotalus molossus (Blacktail rattlesnake), Crotalus pricei (Twin-spotted rattlesnake), Crotalus tigris (Tiger rattlesnake). Endoparasites. Herpetol. Rev. 30:44-45.

Goldberg, S. R., C. R. Bursey, and H. J. Holshuh. 1998. Prevalence and distribution of cystacanths of an oligacanthorhynchid acanthocephalan from the longnose snake, Rhinocheilus lecontei (Colubridae), in southwestern North America. J. Helminthol. Soc. Wash. 65:262-265.

Goldberg, S. R., C. R. Bursey, and R. Tawil. 1993. Gastrointestinal helminths of the western brush lizard, Urosaurus graciosus grociosus (Phrynosomatidae). Bull. Southern Calif. Acad. Sci. 92: 43-51.

Harwood, P. D. 1932. The helminths parasitic in the amphibia and reptilia of Houston, Texas, and vicinity. Proc. U.S. Natl. Mus. 81:1-76.

Ingles, L. G. 1933. Studies on the structure and life-history of Zeugorchis syntomentera Sumwalt, a trematode from the snake Thamnophis ordinoides from California. Univ. Calif. Publ. Zool. 39:163-178.

Leidy, J. 1856. A synopsis of entozoa and some of their ecto-congeners observed by the author. Proc. Acad. Nat. Sci. Philadelphia 42-58.

Mankau, S. K., and E. A. Widmer. 1977. Prevalence of Mesocestoides (Eucestoda: Mesocestoididea) tetrathyridia in southern California reptiles with notes on the pathology in the Crotalidae. Jap. J. Parasitol. 26:256-259.

Mawson, P. M. 1956. Physaloptera variegata Reiber, Byrd and Parker, 1940 from three species of reptiles. Can. J. Zool. 34:75-76.

McAllister, C. T., D. B. Conn, P. S. Freed, and D. A. Burdick. 1991. A new host and locality record for Mesocestoides sp. tetrathyridia (Cestoidea: Cyclophyllidea), with a summary of the genus from snakes of the world. J. Parasitol. 77:329-331.

Meggitt, F. J. 1934. On some tapeworms from the bullsnake (Pityopis sayi), with remarks on the species of the genus Qochoristica (Cestoda). J. Parasitol. 20:181-189.

Morgan, B. B. 1941. A summary of the Physalopterinae (Nematoda) of North America. Proc. Helm. Soc. Wash. 8:28-30.

Pfaffenberger, G. S., N. M. Jorgensen, and D. D. Woody. 1989. Parasites of prairie rattlesnakes (Crotalus viridis viridis) and gopher snakes (Pituophis melanoleucus sayi) from the eastern high plains of New Mexico. J. Wild. Dis. 25:305-306.

Reiber, R. J., E. E. Byrd, and M. V. Parker. 1940. Certain new and already known nematodes from Amphibia and Reptilia. Lloydia 3:125-144.

Rodriguez-Robles, J. A., C. J. Bell, and H. W. Greene. 1999. Food habits of the glossy snake, Arizona elegans, with comparisons to the diet of sympatric long-nosed snakes, Rhinocheilus lecontei. J. Herp. 33:87-92.

Schad, G. A. 1962. Studies on the genus Kalicephalus (Nematoda: Diaphanocephalidae) II. a taxonomic revision of the genus Kalicephalus Molin, 1861. Can. J. Zool. 40:1035-1165.

Stebbins, R. C. 1985. A field guide to western reptiles and amphibians. Houghton Mifflin Co., Boston, xiv + 336 pp.

Sumwalt, M. 1926. Trematode infestation of the snakes of San Juan Island, Puget Sound. Washington University Studies 13:73-101.

Telford, S. R., Jr. 1965. A new species of Thubunaea (Nematoda: Spiruroidea) from California lizards. Jap. J. Exp. Med. 35:111-114.

Voge, M. 1953. New host records for Mesocestoides (Cestoda: Cyclophyllidea) in California. Am. Midl. Nat. 49:249-251.

Widmer, E. A. 1966. Synonymy of Oochoristica crotalicola Alexander and Alexander, 1957. Bull. Wild. Dis. Assoc. 2:82-84.

Widmer, E. A., and O. W. Olsen. 1967. The life history of Oochoristica osheroffi Meggitt, 1934 (Cyclophyllidea: Anoplocephalidae). J. Parasitol. 53:343-349.

Widmer, E. A., and H. D. Specht. 1992. Isolation of asexually proliferative tetrathyridia (Mesocestoides sp.) from the southern Pacific rattlesnake (Crotalus viridis helleri) with additional data from two previous isolates from the Great Basin fence lizard (Sceloporus occidentalis longipes). J. Parasitol. 78:921-923.

Accepted for publication 19 September 2000.

Appendix 1

Museum numbers (LACM) from the Natural History Museum of Los Angeles County for six species of colubrid snakes from California.

Arizona elegans (n = 43) 102030-102035, 102037-102063, 102101-102107, 102109-102111. Chionactis occipitalis (n = 31) 42410, 52292, 52300, 52301, 52306, 52311, 52325, 52327, 52344, 52354, 52361, 52369, 52373, 52378, 52379, 52387-52389, 52401, 52405, 52425, 52430, 63625, 102757-102760, 102762, 102768, 122099, 122100.

Masticophis flagellum (n = 12) 103136, 103138, 103149, 103150, 103153, 103164, 103165, 103172, 103174, 103176, 103178, 103182.

Masticophis lateralis (n = 14) 027794, 027795, 027797, 052540, 052542, 075211, 111203, 111204, 111207, 111210, 111213, 111215, 111216, 111218.

Phyllorhynchus decurtatus (n = 26) 102868, 102874, 102904, 102910, 102913, 102921-102923, 102925-102930, 102934, 102935, 102937, 102939, 102943, 102949-102951, 115876, 115877, 133896, 133897.

Rhinocheilus lecontei (n = 33) 102622, 102624, 102627, 102630-102632, 102634, 102636, 102638, 102639, 102641-102643, 102645-102647, 102655, 102656, 102660-102667, 102669, 102672- 102677.

Appendix 2

Helminths deposited in the United States National Parasite Collection (USNPC) for six species of colubrid snakes from California.

Arizona elegans: Oochoristica osheroffi (90583); Mesocestoides sp. (90425); Physaloptera abjecta (90426); Thubunaea iguanae (90427); Physaloptera sp. (90428). Chionactis occipitalis: Spauligodon goldbergi (90429); Thubunaea iguanae (90430); Physaloptera sp. (90431). Masticophis flagellum: Thubunaea iguanae (90432); Physaloptera sp. (90433).

Masticophis lateralis: Paralechriorchis syntomentera (90434); Oochoristica osheroffi (90435); Mesocestoides sp. (90436); Physaloptera sp. (90437); oligacanthorhynchid cystacanths (90438).

Phyllorhynchus decurtatus: Physaloptera sp. (90439). Rhinocheilus lecontei: Mesocestoides sp. (90441); Thubunaea iguanae (90440); Physaloptera sp. (90442).
Table 1.
Number (N), prevalence (P), mean intensity (M [+ or -] SD),
range (R), and site of infection for helminths of six colubrid
snake species from California.
                                         Arizona
                                         elegans
Helminth species                         (N = 43)
Infection site                     P, M [+ or -] SD, R
Trematoda
  Paralechriorchis synto-
    mentera esophagus                       --
Cestoda
  Oochoristica osheroffi
   small intestine                     [*] 2, 2, --
  Mesocestoides sp. (tetra-
   thyrida) body cavity      12, 128.6 [+ or -] 135.0, 10-299
Nematoda
  Physaloptera abjecta
   stomach                             [*] 2, 1, --
  Spauligodon goldbergi
   large intestine                          --
  Thubunaea iguanae
   stomach, small intes-
   tine                       [*] 9, 5.5 [+ or -] 6.1, 1-14
  Physaloptera sp. (lar-
   vae) intestine               12, 4.4 [+ or -] 6.0, 1-15
Acanthocephala
   oligacanthorhynchid
    cystacanths body cav-
    ity                                     --
                                        Chionactis
                                       occipitalis
Helminth species                         (N = 31)
Infection site                     P, M [+ or -] SD, R
Trematoda
  Paralechriorchis synto-
    mentera esophagus                       --
Cestoda
  Oochoristica osheroffi
   small intestine                          --
  Mesocestoides sp. (tetra-
   thyrida) body cavity                     --
Nematoda
  Physaloptera abjecta
   stomach                                  --
  Spauligodon goldbergi
   large intestine           [*] 45, 12.6 [+ or -] 16.3, 1-58
  Thubunaea iguanae
   stomach, small intes-
   tine                       [*] 23, 3.6 [+ or -] 4.3, 1-13
  Physaloptera sp. (lar-
   vae) intestine               23, 9.9 [+ or -] 6.0, 1-16
Acanthocephala
   oligacanthorhynchid
    cystacanths body cav-
    ity                                     --
                                  Masti-
                                  cophis
                                 flagellum
                                 (N = 12)
Helminth species             P, M [+ or -] SD,
Infection site                       R
Trematoda
  Paralechriorchis synto-
    mentera esophagus               --
Cestoda
  Oochoristica osheroffi
   small intestine                  --
  Mesocestoides sp. (tetra-
   thyrida) body cavity             --
Nematoda
  Physaloptera abjecta
   stomach                          --
  Spauligodon goldbergi
   large intestine                  --
  Thubunaea iguanae
   stomach, small intes-
   tine                        [*] 8, 1, --
  Physaloptera sp. (lar-
   vae) intestine                8, 1, --
Acanthocephala
   oligacanthorhynchid
    cystacanths body cav-
    ity                             --
                                      Masticophis
                                       lateralis
Helminth species                       (N = 14)
Infection site                    P, M [+ or -] SD, R
Trematoda
  Paralechriorchis synto-
    mentera esophagus                [*] 7, 27, --
Cestoda
  Oochoristica osheroffi
   small intestine           [*] 43, 2.8 [+ or -] 1.3, 1-5
  Mesocestoides sp. (tetra-
   thyrida) body cavity      14, 54.5 [+ or -] 74.2, 2-107
Nematoda
  Physaloptera abjecta
   stomach                                --
  Spauligodon goldbergi
   large intestine                        --
  Thubunaea iguanae
   stomach, small intes-
   tine                                   --
  Physaloptera sp. (lar-
   vae) intestine             43, 4.2, [+ or -] 4.6, 1-11
Acanthocephala
   oligacanthorhynchid
    cystacanths body cav-
    ity                                7, 6, --
                                  Phyllo-
                                 rhynchus
                                decurtatus
                                 (N = 26)
Helminth species             P, M [+ or -] SD,
Infection site                       R
Trematoda
  Paralechriorchis synto-
    mentera esophagus               --
Cestoda
  Oochoristica osheroffi
   small intestine                  --
  Mesocestoides sp. (tetra-
   thyrida) body cavity             --
Nematoda
  Physaloptera abjecta
   stomach                          --
  Spauligodon goldbergi
   large intestine                  --
  Thubunaea iguanae
   stomach, small intes-
   tine                             --
  Physaloptera sp. (lar-
   vae) intestine                4, 2, --
Acanthocephala
   oligacanthorhynchid
    cystacanths body cav-
    ity                             --
                                      Rhinocheilus
                                        lecontei
Helminth species                        (N = 33)
Infection site                    P, M [+ or -] SD, R
Trematoda
  Paralechriorchis synto-
    mentera esophagus                      --
Cestoda
  Oochoristica osheroffi
   small intestine                         --
  Mesocestoides sp. (tetra-
   thyrida) body cavity       6, 17.5 [+ or -] 21.9, 2-33
Nematoda
  Physaloptera abjecta
   stomach                                 --
  Spauligodon goldbergi
   large intestine                         --
  Thubunaea iguanae
   stomach, small intes-
   tine                      [*] 23, 5.8 [+ or -] 6.0, 1-17
  Physaloptera sp. (lar-
   vae) intestine               6, 1.5 [+ or -] 0.7, 1-2
Acanthocephala
   oligacanthorhynchid
    cystacanths body cav-
    ity                                    --
(*)Dew host record
Table 2
Characteristics of helminth communities of six species of snakes
from California.
                                          Arizona
                                          elegans
No. snakes examined                       43
No. infected snakes (% infected)          13 (30)
No. helminth species                      5
No. helminths                             690
Mean no. helminths/infected snake         53.0 [+ or -] 102.3
Mean no. helminth species/infected snake  1.2 [+ or -] 0.4'
Dominant helminth                         Mesocestoides sp.
Proportion with 0 helminth species        0.70
Proportion with 1 helminth species        0.23
Proportion with 2 helminth species        0.07
Proportion with 3 helminth species        0.00
                                          Chionactis
                                          occipitalis
No. snakes examined                       31
No. infected snakes (% infected)          21 (68)
No. helminth species                      3
No. helminths                             270
Mean no. helminths/infected snake         12.9 [+ or -] 13.2
Mean no. helminth species/infected snake  1.3 [+ or -] 0.5
Dominant helminth                         S. goldbergi
Proportion with 0 helminth species        0.32
Proportion with 1 helminth species        0.45
Proportion with 2 helminth species        0.23
Proportion with 3 helminth species        0.00
                                          Masticophis
                                          flagellum
No. snakes examined                       12
No. infected snakes (% infected)          2 (17)
No. helminth species                      2
No. helminths                             2
Mean no. helminths/infected snake         1
Mean no. helminth species/infected snake  1
Dominant helminth                         --
Proportion with 0 helminth species        0.83
Proportion with 1 helminth species        0.17
Proportion with 2 helminth species        0.00
Proportion with 3 helminth species        0.00
                                          Masticophis
                                          lateralis
No. snakes examined                       14
No. infected snakes (% infected)          10 (71)
No. helminth species                      5
No. helminths                             184
Mean no. helminths/infected snake         18.4 [+ or -] 33.1
Mean no. helminth species/infected snake  1.6 [+ or -] 0.7
Dominant helminth                         Mesocestoides sp.
Proportion with 0 helminth species        0.29
Proportion with 1 helminth species        0.35
Proportion with 2 helminth species        0.29
Proportion with 3 helminth species        0.07
                                          Phyllorhynchus
                                          decurtatus
No. snakes examined                       26
No. infected snakes (% infected)          1 (4)
No. helminth species                      1
No. helminths                             2
Mean no. helminths/infected snake         2
Mean no. helminth species/infected snake  1
Dominant helminth                         --
Proportion with 0 helminth species        0.96
Proportion with 1 helminth species        0.04
Proportion with 2 helminth species        0.00
Proportion with 3 helminth species        0.00
                                          Rhinocheilus
                                          lecontei
No. snakes examined                       33
No. infected snakes (% infected)          10 (30)
No. helminth species                      3
No. helminths                             84
Mean no. helminths/infected snake         8.4 [+ or -] 10.1
Mean no. helminth species/infected snake  1.1 [+ or -] 0.3
Dominant helminth                         T. iguanae
Proportion with 0 helminth species        0.70
Proportion with 1 helminth species        0.27
Proportion with 2 helminth species        0.03
Proportion with 3 helminth species        0.00
Gale Copyright:
Copyright 2001 Gale, Cengage Learning. All rights reserved.