There's a New Sea Spider in Town

Researchers from the University of British Columbia surveyed shallow habitats across the Salish Sea and identified seven sea spider specimens - five known species and two previously undescribed - marking the first discovery of new regional sea spiders in a century. They sampled depths from the intertidal down to about 60 feet, then used scanning electron microscopy and DNA analysis to classify the animals. The work emphasizes both the rich, understudied diversity in nearshore ecosystems and the effectiveness of combining morphological and genetic tools to reveal cryptic species among small, often parasitic arthropods.

The two new species include Callipallene pilosuspedes, about one centimeter long, named for its hairy feet; it fits within a genus of slender forms lacking claws on the male ovigers and features a triangular mouth rimmed by three sensory-laden lips that give a miniature Sarlacc-like appearance. The other, Tanystylum kiixin, named after a nearby indigenous village, has short rigid legs that collect debris and host micro-ecosystems of single-celled parasites. The findings highlight sea spiders’ ancient arachnid affinities, unusual traits (up to 12 legs, cutaneous respiration, egg brooding on legs, and a proboscis used by some species to feed on hosts), and their ecological roles as tiny mobile habitats and parasites.