Diplocentrus churumuco sp. nov., from the Balsas River Basin in Michoacan, Mexico is described and clearly differentiated from its nearest relatives. The tarsomere II spine formula is 4/4:4/4:5/5:5/5. Pectinal tooth counts are 9- 10 in males, and 7- 8 in…

Paryphoconus peruvianus, a new species from Peruvian Amazonia is described and illustrated from female and male specimens collected at light in the Department of Cuzco. The species is compared with its similar congener P. anomalicornis Kieffer. Furthermore, P. anomalicornis, P.…

A new Pleseobyrsa, P. persea n. sp. is described for Costa Rica. The host plant of this new species is Persea americana P. Mill. This corresponds to the second species of the genus known for the country and the third…

A new species of Lachesilla, from Cabrits National Park, St. John's Parish, Dominica, is here described and illustrated. The phallosome is V-shaped, and it is autapomorphic in having the distal ends of the apodeme arms articulated to each clasper. Based…

Twenty one species and subspecies of Exetastes Grav. are recorded from Mexico. Exetastes arteagus sp. nov., E. gauldi sp. nov. and E. lascivus sp. nov. are described as new. Exetastes pasculus Gauld et Ugalde is recorded for the first time…

Research cruises aboard the R/V "El Puma" were organized to collect deep-water benthic and pelagic specimens off the Pacific coast of Mexico. Seventy four specimens of Holothuroidea were collected off the Pacific coast of Mexico in depths of 377-2 200…