Cinetorhynchus gabonensis, a new species of hinge-beak shrimp (Crustacea: Decapoda: Rhynchocinetidae) from the eastern Atlantic.

A new species of the rhynchocinetid genus Cinetorhynchus, C. gabonensis sp. n. from the Atlantic waters of Gabon, is described based on morphological and molecular comparisons and its distinctive colour pattern. This is the second known species of the genus in the eastern Atlantic, and the third species in the Atlantic as the whole. The new species is more closely related to the western Atlantic C. manningi, both having quadrispinose ambulatory dactyli (i.e. with unguis + 3 ventral spinules), but differs from the latter by the presence of an arthrobranch on the three anterior pereiopods (vs only on the first pereiopod in C. manningi). The branchial formula of the new species is consistent with most of the Indo-West Pacific congeners, and with the amphi-Atlantic C. rigens; the latter possessing trispinose ambulatory dactyli. Other distinctions of the new species from its congeners are in the carpal and meral spinulation of the ambulatory legs, and in the posterolateral and posteroventral armament of pleomeres IV and V. Cinetorhynchus gabonensis sp. n. differs from both known Atlantic congeners also by a specific colour pattern which is dense deep-red mottled with a pair of small white spots delineated by deep-red broad rings on the top of the third pleomere.

Kaviengella jeffkinchi, a new genus and species of symbiotic shrimp (Crustacea: Decapoda: Palaemonidae) from Papua New Guinea.

A very small adult specimen of symbiotic palaemonid shrimp collected from Kavieng Lagoon, N.W. New Ireland Island, Papua New Guinea, is described as a new genus and species. Due to the slender subcylindrical body, reduced rostrum, elongated eyes and distolaterally produced uropodal exopods, the new species is somewhat similar to shrimps of the endosymbiotic sponge genus Nippontonia. Both second pereiopods are lost, but the specimen is unique by its bidentate scaphocerites, an apical corona of spiniform teeth on the mandibular molar process, five posterior telson cuspidate setae from which the median and intermediate ones are long, hooked, and the broadly spoon-like dactyli of the first pereiopods chelae with marginal pectination. Based on those characters, the new genus is without parallel among all symbiotic palaemonid shrimps. Its close phylogenetic relationship to the spongobiotic genera Nippontonia, Onycocaridella, and Thaumastocaris, is also confirmed by molecular comparison.

Periclimenoides tyrannodentatus, a new species of symbiotic shrimps (Crustacea: Decapoda: Palaemonidae) from Taiwan.

A new species of sponge-endosymbiotic shrimps, Periclimenoides tyrannodentatus, is described and illustrated. The species is remarkable for its stout subspatulate first pereiopods chelae with lateral fan-shaped pectination on their dactyli. Due to this character and simple ambulatory dactyli, the new species is similar to the type species of the genus, P. odontodactylus. Another remarkable character is in the unique shape of the minor chela of the second pereiopods; the distal cutting edges of its compressed fingers are distinctly expanded and armed with quite impressive dentitions. An identification key to the three currently recognised species of the genus Periclimenoides is provided. The new species represents the first record of the genus Periclimenoides from Taiwan.