Sinev A.Yu.1, Sanoamuang La-orsi2. 2008. Alona siamensis sp.n., a new species of Cladocera from South-East Asia, related to Alona dentifera (Sars, 1901) (Anomopoda: Chydoridae) // Arthropoda Selecta. Vol.16 (for 2007). No.3: 143–150 [in English].
1 Department of Invertebrate Zoology, Biological Faculty, Moscow State University, Leninskie Gory, Moscow 119991 Russia. E-mail: artem_sinev@mail.ru
2 Applied Taxonomic Research Center, Department of Biology, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand. E-mail: la_orsri@kku.ac.th
KEY WORDS: Cladocera, Alona, new species, South-East Asia, systematics, morphology.
ABSTRACT. A new species of family Chydoridae, Alona siamensis sp.n., inhabiting Malaysia and Thailand, is described. A. siamensis was previously reported from these countries as A. cf. dentifera (Sars, 1901). A. siamensis differs from the most species of Alona in the shape of postabdomen, long, straight basal spine of the postabdominal claw, truncated rostrum, presence of posteroventral denticles, and in IDL armed with two massive, hook-like setae. It differs from A. dentifera in the presence of major head pores (A. dentifera lacks them), prominent sculpture of valves, trunkated rostrum and in hook-like IDL setae.