The family Anchistioididae Borradaile, 1915 (Decapoda: Caridea) is a synonym of Palaemonidae Rafinesque, 1815 based on molecular and morphological evidence

Several systematic revisions of the superfamily Palaemonoidea Rafinesque, 1815 (Natantia) have been published, with molecular studies complementing morphological examination. Yet, the true systematic positions of two families within the superfamily have remained uncertain, one of these being Anchistioididae Borradaile, 1915, the second being Desmocarididae Borradaile, 1915. We constructed a further phylogeny of Palaemonoidea based on two mitochondrial and five nuclear markers to resolve this issue. AnchistioidesPaulson, 1875 (the sole genus of Anchistioididae) is recovered nested within Palaemonidae Rafinesque, 1815, calling into question the validity of Anchistioididae as a distinct family. We also review the morphological characters that have been used to support family level status of Anchistioides including mouthparts adaptations, telson ornamentation, larval morphology, the presence of an appendix interna on the first pleopod in both sexes, and the mandible with a distally flared molar process. Although the latter two characters appear to be synapomorphic to the genus, we contend that these are ambiguous and not well founded to support the family-level status of the genus. As a consequence, and supported by the phylogenetic results, Anchistioididae is herein considered to be a synonym of Palaemonidae.

New record of the sponge-dwelling shrimp Typton distinctus Chace, 1972 (Decapoda: Caridea: Palaemonidae) in São Paulo State, Brazil

Among the Caridea Infraorder, the palaemonid shrimp from the genus Typton Costa, 1844 are commonly found in association with sponges, frequently feeding on the tissues of their hosts ((Ďuriš et al. 2011; Almeida et al. 2014; Pachelle et al. 2015; Soledade et al. 2017). Typton is mostly characterized by morphological features related to their sponge-dwelling lifestyle, as a simple and compressed rostrum, carapace smooth and antennal spines present, antennae extremely reduced and scaphocerite rudimentary. Mandible without palp, incisor process normal, reduced or absent. Second legs unequal, asymmetrical, without molar process on major chela (Bruce, 1972)

Groundwater amphipods (Crustacea, Malacostraca) of India, with description of three new cavernicolous species

Stygofaunistic surveys of peninsular India yielded, among others, three new cavernicolous amphipod taxa: Orientogidiella reducta gen. n., sp. n. in the Borra caves of Andhra Pradesh state, Bogidiella hindustanica sp. n. (Bogidiellidae) and Indoniphargus subterraneus sp. n. (Austroniphargidae) in the Kapiladevi caves of Telangana state. The new genus, Orientogidiella gen. n., is proposed to accommodate all the hitherto known species of the Bogidiella indica-group. This paper gives an illustrated description of the three new species together with their taxonomic affinities. A new record of O. indica comb. n., from the Guthikonda caves in Andhra Pradesh is provided as well. The structure of the Indoniphargus mandible is revisited with scanning electron microscopy (SEM) and revealed a poorly known flexible structure on the molar process which could be useful for phylogenetic purposes. The species diversity and geographic distribution of the Indian stygobiotic amphipods are briefly reviewed.

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.

Saltipedis (Spinosaltipedis) puertoricensis, a new subgenus and species of apseudomorphan (Crustacea: Tanaidacea: Parapseudidae) from coastal waters off Culebra Island, Puerto Rico, with keys and taxonomic observations

Saltipedis (Spinosaltipedis) puertoricensis, n. subgen, n. sp., is described from eastern Puerto Rico off Culebra Island at a depth of 28 m. The new species is the fourth representative of the genus Saltipedis Guţu to be described from the western Atlantic. The new subgenus is distinguished from the currently recognized members of the subgenus Saltipedis Guţu by the presence of strongly developed accessory setae on the mandible between the base of the palp and the molar process. A combination of other characters that further distinguish S. puertoricensis from its congeners includes: (1) rostrum having an acute tip and with lateral margins convex; (2) absence of epistomal spine; (3) setation patterns on the first pereopod, inner margin of uropodal basal article, and the pleotelson; and (4) male chela having a distinct tooth on both the fixed and movable fingers. Pending further systematic study, Longipedis Larsen and Shimomura is resurrected to full generic status. Keys for the separation of the females and known males of Saltipedis are presented. Some of the taxonomic problems defining the genus Saltipedis and related genera are briefly discussed.

A revision of the systematic position of Periclimenaeus spinimanus Bruce, 1969 (Crustacea: Decapoda: Pontoniinae) and the designation of Anisomenaeus gen. nov.

In the course of studying a number of Indo-West Pacific species of the genus Periclimenaeus Borradaile, 1915, it was noticed that Periclimenaeus spinimanus Bruce, 1969, does not fit the current definition of the genus (Bruce 1995), where the species was unfortunately used to illustrate the genus Periclimenaeus. The species is known only from the type specimen collected off Ras Asir, Somalia, at 67.5–73.1 m, during the course of the R.V. Anton Bruun cruise 9 of the International Indian Ocean Expedition in 1964. A preliminary description was provided by Bruce (1969) and later, a more detailed illustrated description (Bruce 1978). The species lacks a molar process on the dactylus and an opposing fossa on the fixed finger of the major second pereiopod, the major diagnostic character of the genus Periclimenaeus Borradaile. A new mono-specific genus is now proposed for its reception.

Phylogenetic analysis using rDNA reveals polyphyly of Oplophoridae (Decapoda:Caridea)

Molecular phylogenetic analysis on nine of the ten genera in the caridean family Oplophoridae Dana, 1852, as well as 14 other caridean families using mitochondrial 16S and nuclear 18S rRNA genes, does not support the monophyletic status of Oplophoridae. Two disparate groups of oplophorids are revealed, with different morphological characters and ecology. It is proposed that the family Oplophoridae is restricted to the three genera Oplophorus, Systellaspis and Janicella. These three genera tend to be distributed in shallower water than the other oplophorid genera, and can also be distinguished from them by certain morphological characters. They have a thicker integument, superficial cuticular photophores and larger eyes, and the molar process of their mandibles is greatly reduced or bears a deep channel. The family Acanthephyridae Bate, 1888 is resurrected for the other seven genera, which are generally distributed in deeper water and are characterised by red soft integument, no cuticular photophores, smaller eyes and well-developed molar process of the mandibles without a deep channel. The relationships between these two families and other caridean families could not be clearly resolved in this study.

A description of a new species of Typhlotanais (Crustacea: Tanaidacea) from West Antarctic with a note on the genus

The male and female of Typhlotanais grahami n. sp., from shallow waters (2 120 m) in Admiralty Bay (South Shetland Islands, the Antarctic) are described. The revision of Typhlotanais sensu lato is currently underway, and there are enough shared characters to place the new species in the same genus. The female of the new species is characterized by (1) a smooth carapace, as long as it is wide; (2) pereonites smoothly rounded laterally; (3) a rounded pleotelson; (4) an undulated, smooth, spineless mandible molar process; (5) nine terminal spiniform setae (two are fused together) on the maxillule; (6) a chela (propodus) of similar size to the carpus, and twice as long as it is wide; (7) a reduced proximal seta on the pleopodal endopod; (8) a uropod exopodite with one article, about 2/3 of the endopodal length, which is longer distally with a large basal part and a bend about a quarter of the way along its length.

Detailed comparative morphology of the peri-oral structures of the Mysidacea and Euphausiacea (Crustacea): an indication for the food preference

Scanning microscope investigations were carried out on mandibles, labrum and paragnaths of several species of Mysidacea and Euphausiacea. Gut content analyses were in agreement with morphological observations. It appears that the morphology of the peri-oral structures and especially of the mandibles reflect the feeding habits, and that the well known relationships between the size of the molar process and the incisor one, i.e. a large molar process is associated with herbivorous feeding, is not always verified. Bacescomysis abyssalis and Bentheuphausia amblyops are believed to be mostly saprophagous, Boreomysis inermis and Meganyctiphanes norvegica are mostly phytophagous, Hemimysis speluncola is omnivorous, while Siriella armata and Thysanopoda orientalis are carnivorous species.