Morphological and molecular descriptions of Moniliformis saudi sp. n. (Acanthocephala: Moniliformidae) from the desert hedgehog, Paraechinus aethiopicus (Ehrenberg) in Saudi Arabia, with a key to species and notes on histopathology.

A new acanthocepohalan species, Moniliformis saudi sp. n. is described from the desert hedgehog, Paraechinus aethiopicus (Ehrenberg), in central Saudi Arabia. Fourteen other valid species of Moniliformis Travassos, 1915 are recognised. The new species of Moniliformis is distinguished by having a small proboscis (315-520 µm long and 130-208 µm wide) with two apical pores, 14 rows of 8 hooks each and small hooks, thre largest being 25-31 µm long anteriorly. Distinguishing features are incorporated in a dichotomous key to the species of Moniliformis. The description is augmented by scanning electron microscopical (SEM) observation and DNA analysis of nuclear (18S rRNA) and mitochondrial (cytochrome oxidase subunit 1; cox1) gene sequences. Attached worms cause extensive damage to the immediate area of attachment in the host intestine. This includes tissue necrosis and blood loss due to damage to capillary beds. Worms also obstruct essential absorbing surfaces.