Koompoot K., Sanoamuang La-orsri. 2021. Parapseudoleptomesochra phayaoensis, a new species of copepod (Copepoda: Harpacticoida: Ameiridae) from a cave in northern Thailand // Invertebrate Zoology. Vol.18. No.1: 1–15 [in English].
Applied Taxonomic Research Center, Department of Biology, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand. E-mail: email@example.com
ABSTRACT: A new species of freshwater harpacticoid copepod, Parapseudoleptomesochra phayaoensis sp.n., was found in a sample collected from a cave in northern Thailand. The new species resembles P. italica Pesce et Petkovski, 1980; however, it differs from P. italica by (1) the armature of baseoendopod and exopod of the fifth leg in both sexes, (2) the setal formula on P1 Exp-3 and P3–P4 Enp-3 and (3) by having a long inner accessory seta (seta VI) on the caudal rami in the female. To our knowledge, this is the first species of the genus Parapseudoleptomesochra Lang, 1965 described in Southeast Asia.
KEY WORDS: cave-dwelling copepod, freshwater, karstic cave, Southeast Asia, stygobionts.