A novel habitat-based approach for combining indices of abundance from multiple fishery-independent video surveys

Microgeographic variation in fitness-relevant traits may be more common than previously appreciated. The fitness of many vertebrates is directly related to their locomotor capacity, a whole-organism trait integrating behavior, morphology, and physiology. Because locomotion is inextricably related to context, I hypothesized that it might vary with habitat structure in a wide-ranging lizard, Podarcis erhardii, found in the Greek Cyclade Islands. I compared lizard populations living on human-built rock walls, a novel habitat with complex vertical structure, with nearby lizard populations that are naive to human-built infrastructure and live in flat, loose-substrate habitat. I tested for differences in morphology, behavior, and performance. Lizards from built sites were larger and had significantly (and relatively) longer forelimbs and hindlimbs. The differences in hindlimb morphology were especially pronounced for distal components – the foot and longest toe. These morphologies facilitated a significant behavioral shift in jumping propensity across a rocky experimental substrate. I found no difference in maximum velocity between these populations, however females originating from wall sites potentially accelerated faster over the rocky experimental substrate. The variation between these closely neighboring populations suggests that the lizards inhabiting walls have experienced a suite of trait changes enabling them to take advantage of the novel habitat structure created by humans.

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

10.21203/rs.3.rs-172910/v1 ◽

2021 ◽

Author(s):

Tatiana S. Leite ◽

Erica A.G. Vidal ◽

Françoise Dantas Lima ◽

Sergio M.Q. Lima ◽

Ricardo M Dias ◽

...

Keyword(s):

New Species ◽

Western Atlantic ◽

Bayesian Phylogenetic Analysis ◽

History Of ◽

Novel Habitat ◽

In Situ Observations ◽

Males And Females ◽

The Relationship ◽

A New Species

Abstract The new species, Paroctopus cthulu sp. nov. Leite, Haimovici, Lima and Lima, was recorded from very shallow coastal waters on sandy/muddy and shelter-poor bottoms with natural and human-origin debris. It is a small octopus, adults are less than 35 mm mantle length (ML) and weigh around 15 g. It has short to medium sized arms, enlarged suckers on the arms of both males and females, large posterior salivary glands (25 %ML), 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 behaviour are a clue to the life history of it and closely related pygmy octopuses. The Bayesian phylogenetic analysis showed that Paroctopus cthulu sp.nov. specimens grouped in a well-supported clade of Paroctopus species, separate from P.joubini and P. cf mercatoris from the Northwestern Atlantic . The description of this new species, living in a novel habitat of human 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.

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