A comparative assessment of the morphology ofProfilicollis altmani(Acanthocephala, Polymorphidae) from crustaceans and shore birds in Peru, with special notes on hook elemental analysis (EDXA), SEM imaging, histopathology, and molecular profile

Abstract

The morphology of cystacanths and adults ofProfilicollis altmani(Perry, 1942) Van Cleave, 1947 (Polymorphidae) were studied from the Pacific mole crabEmerita analoga(Stimpson) (Crustacea, Hippidae) and Belcher’s gullLarus belcheri(Vigors) (Aves, Laridae), respectively, in Peru. Comparative morphometrics with accounts of other populations ofP. altmanifrom elsewhere off the Pacific and Atlantic coasts of North and South America revealed marked intraspecific population variations. We report scanning electron micrographs (SEM) of new features, not before noted or captured in line drawings by earlier observers. We further present microscope images that reveal internal details not previously reported or possible to see with SEM. Energy dispersive X-ray analysis (EDXA) revealed unusual patterns in the chemistry of proboscis hooks especially the high sulfur and diminished phosphorous and calcium in hook tips and low sulfur and high levels of phosphorous and calcium at mid hooks. The size and shape of all hooks of the cystacanths are reported for the first time. Histopathological studies inL. belcherifrom Peru are also included. Cystacanths ofP. altmanifrom California were also analyzed for molecular patterns and compared with other sequences reported from other locations. The molecular data and the analysis of our new sequences of cytochrome oxidase I (COI) showed that haplotypes ofP. altmanihad low genetic variation; the species is not geographically structured, and within its clade no monophyletic group is formed.