ABSTRACT
We investigated ectoparasite diversity, interspecific infestation rates and host preference in roosting fruit bats, Eidolon helvum, from Bowen University, Southwest Nigeria. Fur of captured E. helvum were sampled monthly for ectoparasites from January 2021 to June 2022. We examined a total of 231 E. helvum and observed a significant female to male adult sex ratio (0.22:1); with 53.9% ectoparasitic infestation rate. We identified and enumerated the ectoparasite; and subjected its Cytochrome c oxidase subunit I (COI) gene to phylogenetic analysis with other nycteribiids. COI gene sequences obtained formed a distinct clade with other C. greeffi sequences. We recovered a total of 319 (149 female and 170 male) ectoparasites and observed a balanced C. greeffi female to male adult sex ratio of 0.88:1. Ectoparasitic sex distribution had no association with host sex and season. Prevalence was significantly higher during the wet season, but not between sexes of E. helvum. The intensity of infestation, 3.7 ± 0.4 individuals per fruit bat, was significantly higher during the wet season with a bimodal seasonal distribution. The strongly male-biased host adult sex ratio had no significant influence on C. greeffi metapopulation adult sex ratio.
ABSTRACT
Prorocentrum lima (CSIRCSMCRI005) was isolated from the coastal seawater of Thonithurai, Tamil Nadu, India. Morphology of the isolate was studied using light microscopy (LM) and scanning electron microscopy (SEM) while phylogenetic analyses of the internal transcribed spacer region (ITS1-5.8s-ITS2), 18S rDNA, and large subunit (LSU) rDNA were also carried out. Growth of the isolate was studied, and okadaic acid (OA) production was examined using liquid chromatography with electrospray ionization and quadrupole time of flight mass spectroscopy (LC-ESI-Q-ToF-MS). Morphological features observed including oval cell shape with a broad middle region, narrow anterior and round posterior end, large central pyrenoid with starch sheath, smooth thecal surface, and V-shaped periflagellar area consisting of eight platelets matched with the description of the type species and those reported elsewhere. The ITS, 18S, and LSU sequence phylogenetic analysis revealed that the isolate was closely related to other strains reported from the pacific. The growth rate (µ) was 0.05 div. day-1. P. lima CSIRCSMCRI005 produced okadaic acid and related esters. The production of free and total OA was 20.12 ± 4.77 and 22.30 fg cell-1, respectively. The findings of this study contribute useful information concerning the regional risk of diarrheic shellfish poisoning in the North East Indian Ocean and the global distribution and toxic potential of Prorocentrum lima. Further studies on the ecophysiology of this strain will be helpful. This manuscript reports the detailed morphological, phylogenetic, and toxicological characterization of this species from the Bay of Bengal and the North Indian Ocean as a whole.
