Collections unravelled: Loman’s Pycnogonids

Jan Cornelis Christiaan Loman (1856–1929) was a major contributor to our knowledge of sea spiders (Arthropoda, Pycnogonida) and to the collections of the Naturalis Biodiversity Center (NBC), Leiden. Loman worked on Pycnogonida material from various geographic origins, including southern Africa, the Antarctic Peninsula, Arctic seas, Southeast Asia, the Atlantic, Australia, the China Sea, Japan, and the Mediterranean Sea; he notably participated in the taxonomic study of samples from the Siboga Expedition, the Prince Albert I of Monaco expeditions, and the Swedish Antarctic Expeditions. In total, Loman described 54 sea spider species and six sea spider genera; 48 and three, respectively, are still regarded as valid today. In the present work, we aim to summarise Loman’s outstanding contribution to sea spider taxonomy by listing all species he reported or described. We recovered a total of 162 records in NBC, 133 of which correspond to type material, including 19 holotypes and 37 syntypes. We further sought out all Loman’s Pycnogonida material curated at NBC and located additional type material housed in institutions worldwide.