. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 386 J. O'BRIEN Comparisons of linear regressions were done by ANCOVA based on a program from Zar (1974). RESULTS Host size distribution No parasitized host was found larger than 85 mm. Only of the parasitized population (3 crabs) was larger than 80 mm, although of the unparasitized adult population exceeded this size (Fig. 1). Mean size of parasitized adults [ mm ± () (n =: 730)] was significantly less than the respective mean sizes of unparasitized adult females and males [ mm ± (n = 1846) and
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 386 J. O'BRIEN Comparisons of linear regressions were done by ANCOVA based on a program from Zar (1974). RESULTS Host size distribution No parasitized host was found larger than 85 mm. Only of the parasitized population (3 crabs) was larger than 80 mm, although of the unparasitized adult population exceeded this size (Fig. 1). Mean size of parasitized adults [ mm ± () (n =: 730)] was significantly less than the respective mean sizes of unparasitized adult females and males [ mm ± (n = 1846) and ± (n - 1615)] (P < , Student's Mest). Using probability graph paper the size frequency distribution of parasitized adult crabs was separated into three modes. The first mode had a mean of 56 mm and comprised 62% of the parasitized population. Succeeding modes had means of 67 and 79 mm constituting 35% and 3% of the population respectively. Percentage of hosts parasitized (prevalence) within the total adult population was Prevalence decreased with increasing host size above a carapace length of 57 mm (Table I). Almost 90% of the parasitized population was found between 46 and 69 mm carapace length (Table I). Molt increment Linear regressions of molt increments (post-molt length - - pre-molt length) of immature crabs as a function of pre-molt carapace lengths were: parasitized crabs (Y - + , r = , n = 22), unparasitized females (Y = - , r = , n = 75) and unparasitized males (Y = + , r = , n = 65). When subjected to ANCOVA at P = , no significant difference between these regressions in slope or elevation was found whether parasitized crabs were 250 200 — H unparasitized a 150 « 100 50 parasitized. )l / / - •••••••••••••••iiJMB _ ' L » 8" 0~l /30 40 50 60 70 80 90 100 115 PUG€TTIA PRODUCTA CARAPACE LENGTH [mm] FIGURE 1. Size-frequency distribution of unpa
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
