An annotated checklist and keys to the species of Copepoda Harpacticoida (Crustacea) Author Wells, J. B. J. text Zootaxa 2007 2007-08-31 1568 1 1 872 https://biotaxa.org/Zootaxa/article/view/zootaxa.1568.1.1 journal article 10.11646/zootaxa.1568.1.1 1175­5334 5096323 7F32B238-224A-4079-B0E0-D5003C7F185A Family Cylindropsyllidae KG 0 – characters 1. Caudal ramus spur ­ dorsal side with an upwardly directed horn­like spur simple ­ without such a structure 2. P1 Exp­2, spine at outer distal corner present or absent 3. Maxilliped wd ­ well developed; subchelate vest ­ vestigial or absent 4. P2–P4 Exp­3 n:n:n ­ number of setae and spines on P2, P3 and P4 mod ­ modified (see note 2)