Juxtastenopus
Juxtastenopus spinulatus is a species of stenopodidean shrimp. It lives in the Red Sea, and across the Indian Ocean as far east as the Philippines. It is red or pink, up to long, with enlarged third pereiopods. Originally described in the genus "Engystenopus", it is now placed in the monotypic genus Juxtastenopus, in the family Stenopodidae. Description. "Juxtastenopus" grows to a total body length of long (carapace length: ). In life, the animals are red or pinkish, but with white tips to the chelae (claws) on the enlarged third pereiopods (walking legs). Females are reproductive at lengths around , and carry  between 27 and 132 eggs, each initially in diameter. Distribution. Most specimens of "J. spinulatus" have been collected from the Red Sea at depths of , where the water is warm. That warm water mass drops to a depth of on passing through the Bab-el-Mandeb strait into the Gulf of Aden, and "J. spinulatus" has also been collected at a depth of in the Gulf of Aden. It also occurs in the Indian Ocean, and as far east as Hong Kong and the Philippines, but occurs in much shallower water than in the Red Sea. Taxonomy. The earliest discovered  specimens of "J. spinulatus" were assigned by Heinrich Balss to the species "Stenopus spinosus". Its first description as a separate species was the type description by Lipke Holthuis in 1946, where it was given the name "Engystenopus spinulatus". This was based on a single damaged holotype male, collected in the Lobetoli Strait, east of Flores, Indonesia, and the placement in the genus "Engystenopus" was considered questionable. The most distinctive characteristics of "Engystenopus" are characters of the third pereiopod, which was lacking from all the early specimens. When specimens with intact third pereiopods became available, Joseph Goy realised that ""E. spinulatus  did not belong in the same genus as "E. palmipes" (the only other species of "Engystenopus"), and erected a new genus, "Juxtastenopus", to hold it. The two genera are now placed in different families, although both names carry the meaning "close to "Stenopus""; "Engystenopus" is one of seven extant genera in the family Spongicolidae, while "Juxtastenopus" is one of four extant genera in the family Stenopodidae.