A new species of pygmy Paroctopus Naef, 1923 (Cephalopoda: Octopodidae): the smallest southwestern Atlantic octopod, found in sea debris

• Published in: Marine biodiversity Vol. 51; no. 4; p. 68
• Main Authors: Leite, Tatiana S., Vidal, Erica A. G., Lima, Françoise D., Lima, Sergio M. Q., Dias, Ricardo M., Giuberti, Giulia A., de Vasconcellos, Davi, Mather, Jennifer A., Haimovici, Manuel
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.08.2021; Springer Nature B.V
• Subjects: Animal Systematics/Taxonomy/Biogeography; Anthropocene; Bayesian analysis; Biodiversity; Biomedical and Life Sciences; Cephalopoda; Coastal waters; Debris; Eggs; Females; Freshwater & Marine Ecology; Juveniles; Life history; Life Sciences; Marine debris; Marine molluscs; Morphology; New species; Octopuses; Original Paper; Phylogenetics; Phylogeny; Plant Systematics/Taxonomy/Biogeography; Probability theory; Shallow water; Brazil; Rio de Janeiro Brazil; Gulf of Mexico; Caribbean Sea; Anthropocene; Phylogeny; Octopus; Marine debris; Integrative taxonomy; Brazilian coast
• ISSN: 1867-1616; 1867-1624
• DOI: 10.1007/s12526-021-01201-z

The new species, Paroctopus cthulu sp. nov. Leite, Lima, Lima and Haimovici was recorded from shallow coastal waters of south and southeastern Brazil, where most specimens were found sheltered in marine debris. It is a small octopus; adults are less than 35 mm mantle length (ML) and weight around 15 g. It has short- to medium-sized arms, enlarged suckers on the arms of both males and females, a relatively large beak (9% ML) and medium to large mature eggs (3.5 to > 9 mm). The characteristics of hatchlings of two brooding females, some of their anatomical features, and in situ observations of their behavior are a clue to the life history of it and closely related pygmy octopuses. The Bayesian phylogenetic analysis showed that Paroctopus cthulu sp. nov. is grouped in a well-supported clade of Paroctopus Naef, 1923 species, clearly distinct from Octopus joubini Robson, 1929 and Paroctopus mercatoris (Adam, 1937 ) from the Northwestern Atlantic . The description of this new species, living in habitat altered by humans, debris in shallow water off Brazil, offered an opportunity not only to evaluate the relationship among the small octopuses of the western Atlantic, Caribbean and eastern Pacific, but also their adaptation to the Anthropocene period.