Composition of the Helminth Community of a Montane Population of the Side-Blotched Lizard, Uta Stansburiana (Phrynosomatidae) from Los Angeles County, California
Goldberg, Stephen R., Bursey, Charles R., Cheam, Hay, The American Midland Naturalist
ABSTRACT.-Six hundred sixty-three Uta stansburiana from the San Gabriel Mountains, Los Angeles County, California collected at monthly intervals from February 1974 to January 1975 were examined for helminths. One species of cestode, Ooc*onstica macallisteri, two species of nematodes, Physaloptera retusa (larvae) and Spanligodon giganticus and one species of an oligacanthorhynchid acanthocephalan (cystacanths) were found. Spauligodongiganticus had the highest prevalence (23%) and greatest mean abundance (1.0 3.7 SD). It was present in 11 of the 12 mo studied. This is the first report of an oligacanthorhynchid acanthocephalan for LT stansbuiana. Infection prevalences and mean intensities appear to be determined by a lizard's position within the habitat and its behavior patterns.
The side-blotched lizard, Uta stansburiana Baird and Girard (1852) ranges from central Washington through Baja California and northern Zacatecas, Mexico to west Texas and western Colorado from below sea level to around 2750 m elevation (Stebbins, 1985). It is a short-lived lizard with mean life expectancy of 1.1 to 1,4 y (Tinkle, 1967). There are three previous reports of helminths from this lizard (Rothman, 1954; Telford, 1970; Bursey and Goldberg, 1996). The purpose of this paper is to report the occurrence of helminths in a montane population of U. stansburiana and to comment on other helminths harbored bv this host.
MATERIALS AND METHODS
Six hundred sixty-three I rta stansburiana were examined for helminths: 510 were collected at 1585 m elevation (mean snout-vent length [SVL] = 44.8 6.8); 153 at 1829 m (SVL = 46.8 5.8) in the San Gabriel Mountains, Los Angeles County, California (34o18'N, 117o50'W) from February 1974 to January 1975. Lizards were killed by injection of sodium pentobarbitol, fixed in 10% formalin and preserved in 70% ethanol. They were used in a reproductive study (Goldberg, 1977) then deposited in the herpetology collection of the Natural History Museum of Los Angeles County, LACM 12014120892. Terminology is in accordance with Bush et al. (1997). Voucher helminths were deposited in the U.S. National Parasite Collection, Beltsville, Maryland: Oochoristica macallisteri, 87280; Physaloptera retusa, 87282; Spauligodon giganticus, 87281; oligacanthorhynchid acanthocephalan cystacanths, 87283. Each nematode was examined and identified using the standard glycerol wet mount procedure. Cestodes were regressively stained with hematoxylin and mounted in balsam.
Field observations.-The San Gabriel Mountain habitat from which Uta stansburiana was collected consisted primarily of rocky outcrops and boulders interspersed with evergreen forest (Pinus ponderosa, P jeffreyi, Pseudostuga macrocarpa, Calocedrus decurrens); there was a predominance of chaparral vegetation (Arctostaphylos sp., Cercocarpus sp.) on southern exposures. Uta stansbunana was often seen on rocks, in interstices in rock fields and was occasionally observed to "lick" substrate, presumably for environmental cues.
In this habitat, Uta stansburiana was active throughout the year; however, low temperatures November-February and high temperatures June-September restricted daily activity. May was the month of greatest activity. October was second in the amount of observed activity. The 1829 m site was subject to greater snow accumulations than the 1585 m site; however, the typical bimodal activity period of May and October was observed.
Laboratory observations.-The samples were treated as a single population (SVL = 45.2 mm 6.6 SD, range 21-60 mm) because bet veen collection sites, there was no statistical difference in SVL (paired t test = 0.5, P > 0.05), prevalence of infection (Kruskal-Wallis test = 0.08, 1 df, P > 0.05), mean intensity (Kruskal-Wallis test = 2.34, 1 df, P > 0.05) nor, with the exception of the single acanthocephalan infection, were there differences in the helminth species present. …