Systematics and Phylogenetic Relationships of New Zealand Benthic Octopuses (Cephalopoda: Octopodoidea)

Abstract

The systematics of the New Zealand octopods have only been reviewed twice in the last 100 years. In these revisions many species have been provisionally classified in the genus Octopus. Recent genetic studies have synonymized some New Zealand species with octopuses from other regions. The present study investigates the systematics and phylogeny of octopuses from New Zealand using eighty eight specimens, three mitochondrial genes (16S rRNA, cytochrome c oxidase subunit I, and cytochrome c oxidase subunit III) and one nuclear gene (Rhodopsin). Forty-four new octopod DNA sequences (belonging to 13 species) were included, adding to the 83 existing sequences from GenBank. All sequences were used to generate phylogenetic trees based on Maximum Likelihood (ML) and Bayesian inference (BI), with a data set composed by 97 species, including octopod sister groups and Vampyroteuthis infernalis as an outgroup. Gene tree and species delimitation analyses revealed a distinct genetic difference between two sympatric Graneledone subspecies, which we propose as valid species. Muusoctopus tangaroa is a sister species of M. thielei from Kerguelen; while Enteroctopus zealandicus forms a clade with E. megalocyathus from South America and E. dofleini from the North Pacific. Similarly, Octopus campbelli, O. huttoni, and O. mernoo form a monophyletic group with Robsonella fontaniana from South America, Scaeurgus unicirrhus from the Atlantic and O. pallidus from Australia. Pinnoctopus cordiformis is close to Grimpella thaumastocheir and several species of Octopus sensu lato as in previous phylogenetic studies. This study suggests that octopuses from New Zealand have different phylogenetic and biogeographic origins and represent independent radiations into this region.

A first look at the genetic diversity of Enteroctopus megalocyathus (Cephalopoda: Enteroctopodidae) captured by the king crab fishery in the south of Chile

“…The second hypothesis is that E. megalocyathus , E. magnificus and E. zealandicus are conspecifics. This suggests that one Enteroctopus species occurs along the southern hemisphere, which is evidenced by the close relationship between the three taxa in the phylogenetic trees resolved in the present study, and previously stated in other studies (Hudelot, 2000 cited by Norman et al ., 2014; Ibañez et al ., 2020). However, both E. megalocyathus and E. zealandicus differ morphologically from each other in several characteristics (Ibáñez et al ., 2020).…”

Species Delimitation of Argonauta Paralarvae Reveals an Extensive Morphological Variability in the Northern Humboldt Current System

“…This molecular identification tool uses a short and standardized section of the mitochondrial gene Cytochrome Oxidase I (COI) [17] and has been proven efficient in evaluating diversity in the marine ecosystem [18,19]. Recently, molecular data together with species delimitation methods were used to reveal the diversity of cephalopods [20][21][22][23].…”