Belongs within: Phoxichilidiidae. The Callipallenidae are a family of sea-spiders generally retaining chelifores but lacking palpi, though the phylogeny of Pycnogonida recovered by Siveter et al. (2004) placed Nymphon (which possesses both chelifores and palpi) and Pycnogonum (which lacks both) within the clade of callipallenid genera. Pycnogonum species are robust-bodied sea-spiders with relatively short legs.… Continue reading Callipallenidae


Belongs within: Phoxichilidiidae. Sea spiders Published 16 January 2021 With arthropods being such a massively diverse sector of the global biota (and even that feels like an understatement; describing arthropods as ‘very diverse’ seems a bit like describing the Andromeda Galaxy as ‘very far away’), it is only to be expected that it contains some… Continue reading Anoplodactylus


Belongs within: Euarthropoda.Contains: Ammotheidae. The Pycnogonida, sea-spiders, are a group of highly distinctive marine arthropods with a tubular body bearing four to six pairs of walking legs. Feeding is via a tubular proboscis at the front of the cephalosoma, which also bears up to four pairs of appendages (the chelifores, palpi, ovigers and the first… Continue reading Pycnogonida