Morphological and molecular characterization of two new species ofAndracantha(Acanthocephala: Polymorphidae) from New Zealand shags (Phalacrocoracidae) and penguins (Spheniscidae) with a key to the species

Abstract

Two new species of Andracantha (Polymorphidae) are described from the intestine of the shags Leucocarbo chalconotus (Gray) and Phalacrocorax punctatus (Sparrman), and the penguin Eudyptula minor (Forster) from southern South Island, New Zealand. Andracantha leucocarboi n. sp. is distinguished from its congeners by having no genital or ventral trunk spines, but possessing a scattering of small spines between the anterior fields of spines. This is the first record of a species of Andracantha from a penguin. Circumbursal papillae are illustrated in a scanning electron micrograph for the first time in the polymorphids. Andracantha sigma n. sp. is distinguished by the sigmoid shape of its largest proboscis hook, hook VIII, and having the ventral field separated from the posterior disc field by an aspinous gap. A Maximum Likelihood tree from cox1 and large ribosomal subunit (LSU) data shows A. leucocarboi n. sp. to be more closely related to A. gravida than A. sigma n. sp. and the genus Andracantha as sister to Corynosoma spp. Genetic distances between species of Andracantha are comparatively large. A key to the species of Andracantha is provided.

Morphological updates and molecular description of Heterosentis holospinus Amin, Heckmann, & Ha, 2011 (Acanthocephala, Arhythmacanthidae) in the Pacific Ocean off Vietnam

“…Various studies have suggested that the classification of acanthocephalans based only on morphological characters is unstable due to the existence of a conservative and simple morphology [12, 19, 34, 36]. Our findings, in accordance with those of previous studies [17, 36, 41] substantiate that the classification of Palaeacanthocephala needs adjustments. We found that two families, Echinorhynchidae and Rhadinorhynchidae, are not monophyletic.…”

Molecular characterisation of acanthocephalans from Australian marine teleosts: proposal of a new family, synonymy of another and transfer of taxa between orders

“…However, a number of modern studies characterising acanthocephalan taxa (e.g. Rosas-Valdez et al, 2012;Pinacho-Pinacho et al, 2015Presswell et al, 2018;García-Varela & Pinacho-Pinacho, 2020) have omitted generation of 18S rDNA sequences, opting instead to produce ITS and/or cox1 barcodes and short 28S rDNA sequences. Although the alignment of 28S rDNA sequences in the present study includes far more gap-positions and short sequences than the 18S sequence alignment, the trees recovered from analyses of the 28S dataset are largely congruent with those obtained from the 18S dataset.…”

New Records on Acanthocephalans from California Sea Lions Zalophus californianus (Pinnipedia, Otariidae) from California, USA

“…Remarks. Th e genus Andracantha now comprises nine valid species (Schmidt, 1975;Amin, 2013;Presswell et al, 2017). Th e specimens found in the present study closely resemble Andracantha baylisi (Zdzitowiecki, 1986) based on the shape and size of the body and hooks, arrangement of the tegumental spines and location of the gonopore in females.…”