Phylogenetic assessment of a new species of Amigdoscalpellum Zevina, 1978 (Cirripedia: Scalpellidae) associated with caryophyllid cup corals from New Zealand, with a key to the genus.

The article focuses on the description and phylogenetic analysis of a new deep-sea scalpellid barnacle species, *Amigdoscalpellum calicicolum* sp. nov., from northern New Zealand. This species is uniquely associated with solitary cup corals of the genus *Caryophyllia*, where it is partially embedded or overgrown by the host coral's skeleton, and exhibits distinctive morphological traits such as a transversely arched carina and an expanded carinolatus plate. Molecular analyses based on mitochondrial and nuclear DNA place *A. calicicolum* within a clade of *Amigdoscalpellum* species, although the overall taxonomy of the family Scalpellidae remains unsettled due to limited molecular data and morphological variability. The study also discusses the ecological relationship between the barnacle and its coral host, noting the barnacle's orientation and potential feeding strategy, and provides an updated key to species within the genus *Amigdoscalpellum*.