Abstract:

This study examined the relationship between the metazoan parasite community in a focal species, Fundulus heteroclitus, and the species richness of the free-living community. Four distinct salt marsh areas were selected in order to reflect a gradient in free-living species richness and time post-restoration (unrestored, 0, 10, and 20 yr post-restoration). A total of 960 fish was studied, with 30 collected per site in each of 8 consecutive seasons between 2005 and 2007. Species richness and abundance of birds, fish, and benthic macroinvertebrates varied significantly between sites. However, increasing richness in the free-living community was neither positively nor negatively correlated with richness in the parasite infracommunity in F. heteroclitus. These results demonstrate that the relationship between community species richness and parasite richness is not linear. The data suggest that the diversity of parasites may be more correlated with measures of community composition, such as the structure and cohesiveness of the food web, rather than with prevailing measures of biodiversity.

Abstract:

Hairworms infect terrestrial arthropods and are 1 of the most understudied groups of parasites. Recently, life cycles of 2 gordiids (Paragordius varius and Paragordius obamai) have been domesticated in the laboratory. We tested the viability of laboratory reared and post-frozen larval and cyst stages of the North American gordiid, P. varius, frozen at −80 C for 7 mo, and the viability of field collected and post-frozen cysts of the African (P. obamai) and North American (P. varius) gordiid frozen at −20 C for 2 mo. All snails exposed to post-frozen or control P. varius larvae became infected with cysts, and there was no significant difference in prevalence or mean intensity of cysts among control or experimental snail groups. As with larvae, no significant differences were observed in prevalence or mean intensity of emerging worms from crickets infected with post-frozen or control P. obamai or P. varius cysts. All female P. obamai and P. varius worms from control and post-frozen cyst infections laid eggs and larvae hatched from some of these eggs. Survival and cyst formation of P. varius larvae exposed to different combinations of drying and/or freezing temperatures indicated that gordiid larvae have the ability to survive drying and freezing, but survival significantly increases during freezing at lower temperatures. The major contribution of our study is the demonstration that gordiid larval and cyst stages can survive freezing temperatures to infect and develop in the next host.

Abstract:

Populations of several species of gregarine parasites within a single host species, the damselfly Ischnura verticalis, were examined over the course of 1 season at 4 geographic localities separated by a maximum distance of 9.7 km. Gregarines, having a life cycle with both exogenous and endogenous stages, are subject to a wide variety of selective pressures that may drive adaptation. Gregarine species showed some specificity for host life cycle stage, i.e., Steganorhynchus dunwoodyi and Hoplorhynchus acanthatholius were most prevalent in larval hosts while Steganorhynchus dunwoodyi, Actinocephalus carrilynnae, and Nubenocephalus nebraskensis were most prevalent in adult hosts. Species prevalence and abundance differed by geographic locality. Gregarine prevalence was significantly higher in adult female damselflies than in males at 2 localities; sex differences in prevalence were insignificant for larval damselflies at all 4 localities. In larval hosts, gregarine abundance was independent of age (size). The present study, therefore, shows that pond characteristics, host life cycle stage, and adult host sex are the main factors that influence the prevalence and abundance of gregarine populations.

In Vieira et al., 99: 327–331, Figures 14 and 15 are mentioned, but there are no Figures 14 and 15; and Table I below was omitted from the article.

MEROGONY AND PHYLOGENY OF HEPATOZOON RAWASHI PARASITIZING HASSELQUIST’S FAN-FOOTED GECKO, PTYODACTYLUS HASSELQUISITI (SAURIA: PHYLODACTYLIDAE) IN EGYPT

A. S. Abdel-Baki,

Lamjed Mansour,

Saleh Al-Quraishy, and

Donald W. Duszynski

REVISION OF THE LECANICEPHALIDEAN GENUS FLAPOCEPHALUS DESHMUKH, 1979 (EUCESTODA) FROM COWTAIL RAYS (GENUS PASTINACHUS RÜPPELL) (MYLIOBATIFORMES: DASYATIDAE JORDAN AND GILBERT) WITH THE DESCRIPTION OF FOUR NEW SPECIES