Sexual dimorphism in the methane seep-dwelling Costa Rican yeti crab Kiwa puravida (Decapoda: Anomura: Kiwaidae)

Deep-sea chemosynthesis-based ecosystems support unique biological communities, but human impacts are an increasing threat. Understanding the life-history traits of species from deep-sea can help to develop adequate management strategies, as these have on ecological responses changes in environment. Here we examined occurrence sexual dimorphism yeti crab Kiwa puravida , endemic Costa Rican Pacific margin that aggregates at active methane seeps and depends chemosynthetic bacteria for nutrition. The two morphological features included claws, suspected be under selection used defense, carpus second pereopod not selection. A total 258 specimens, 161 males, 81 females, 16 juveniles, were collected Mound 12 1,000-1,040 m depth 2017 2018 analyzed. We found males larger wider claws than while there no differences length. These results suggest claw weaponry is K . which probably related mating system this species. This first attempt study reproductive biology additional observations will necessary shed more light matter.