Redescription of Caridina sobrina Riek, 1953 stat. nov. and description of a new species of Caridina from south-eastern Queensland (Decapoda, Atyidae).

Caridina sobrina Riek, 1953, only known from Fraser Island (Queensland, Australia), is redescribed and elevated from subspecies to species level. A morphologically very similar species, Caridina pagei sp. nov., is described from nearby Moreton Island. The taxon known in previous literature as Caridina sp. C2 is also illustrated but left unnamed in view of its complete morphological overlap with C. pagei, despite substantial genetic drift.

The curious case of "innies": Articles 50.1, 50.1.1 and the citation of authorities in Decapoda Crustacea-a way forward.

In the majority of species and genus names in Decapoda Crustacea, the author(s) of the name equate with the author(s) of the work. In a relatively small number of cases, however, the author(s) of the name are either a subset of the authors of the work or are not an author on the work-a phenomenon herein termed "innies". We demonstrate that these two categories should be differentially interpreted according to Articles 50.1 and 50.1.1 of the ICZN Code. To promote stability in cited authorship of historical names, it is proposed that 1) if the author(s) of the name are also an author on the work, these should be universally accepted as "innies", irrespective of any further explanation in the text (including a mere attribution following the taxon name); and 2) that if the author(s) of the name are not an author(s) of the work, these should only be considered as "innies" if a more expansive explanation is given in the text, not merely an attribution of authorship to the taxon name.

Opaepupu, a new genus and species of bivalve-associated shrimp (Decapoda: Caridea: Palaemonidae) from Hawai'i.

A new palaemonid shrimp genus, Opaepupu gen. nov., is established to accommodate a new species of bivalve-associated shrimp, Opaepupu huna sp. nov. from Hawaii. A single mated pair, the female holotype and the male allotype, were found inside the trapezid bivalve Trapezium oblongum (Linnaeus, 1758) at a depth of 14 m in Kâne'ohe Bay, Hawai'i. The new genus is characterised by the rostrum being proximally broad, distally pointed, mid-dorsally carinate, and non-dentate; the anterolateral margin of the carapace without supraorbital, hepatic or epigastric teeth, but with a strong sharp antennal tooth; the sixth pleonite posteriorly unarmed; the telson medially depressed, with the dorsal surface armed with two pairs of submarginal cuspidate setae and with the posterior margin armed with two pairs of spiniform setae; the distolateral angle of the first article of the antennular peduncle without a sharp tooth; the mandible without a palp; the maxillular palp furnished with one long stiff seta dorsal to a small tooth-like extension; the first maxilliped without a palp; the third maxilliped not being operculate; the second pereiopods moderately robust, relatively slender, subequal, subsymmetrical, with simple teeth on the cutting edges of the fingers; the ambulatory pereiopods being slender, each ending in an elongate biunguiculate dactylus; and the uropodal exopod with a faint diaeresis and greatly reduced distolateral spiniform seta. The phylogenetic position of Opaepupu gen. nov. remains unclear, although it does not appear to be closely related to other bivalve-associated palaemonid genera.

On the systematic status of Isopericlimenaeus Marin, 2012 and its type species, Periclimenaeus gorgonidarum (Balss, 1913) (Crustacea: Decapoda: Palaemonidae).

The palaemonid genus Isopericlimenaeus is currently comprised of only the type species, Isopericlimenaeus gorgonidarum, with the diagnostic character of the genus being the presence of a molar and fossa structure on both second chelipeds. Periclimenaeus uropodialis is a closely related species, which has either been considered a synonym of I. gorgonidarum or placed as a valid species in the related genus, Periclimenaeus. During fieldwork in the Philippines, Taiwan and Korea, several species of Periclimenaeus and other sponge associated shrimps belonging to the family Palaemonidae were collected, including I. gorgonidarum and P. uropodialis. Based on a morphological and molecular comparison, it is demonstrated that both taxa are conspecific and that Isopericlimenaeus is a junior synonym of Periclimenaeus.

A new species of the genus Cristimenes Duris & Horká, 2017 (Decapoda, Caridea, Palaemonidae).

A new species of crinoid-associated shrimp, Cristimenesbrucei sp. nov., is described based on specimens from Korea, although the species also occurs in Hong Kong and is likely more widespread. The new species is morphologically very similar to C.commensalis, but can be distinguished by the reduced supraorbital tooth on the carapace. Cristimenesbrucei sp. nov. is clearly recovered as a monophyletic species through COI barcode and molecular phylogenetic analyses based on four genetic markers (COI, 16S, H3, 18S).

A new, distinctly coloured species of Lysmata Risso, 1816 (Malacostraca: Decapoda: Lysmatidae) from the south-central Atlantic.

A new species of the caridean shrimp genus Lysmata Risso, 1816 is described from St. Helena and Ascension Island in the south-central Atlantic. Lysmata napoleoni sp. nov. is part of the so-called "long-branch group" of the genus and shows a strong morphological similarity with the eastern Atlantic L. seticaudata Risso, 1816, from which it can be distinguished by details of the accessory branch of the antennular flagellum. The new species also displays a unique and bright colour pattern and therefore can be easily recognised in the field. Furthermore, it is typically found in proximity of sea anemones, Telmatactis cricoides (Duchassaing), and appears to be an occasional fish cleaner.

Notes on the shrimp genus Palaemon Weber, 1795 (Crustacea, Decapoda, Palaemonidae) and related genera from Taiwan.

The shrimp genus Palaemon Weber, 1795 and its related genera in Taiwan are reviewed based on newly collected specimens, whilst older records are critically reviewed. Five genera and 11 species are now known to occur in Taiwan, although there are no recent records for Palaemon modestus (Heller, 1862), which could be nationally extinct. The records of P. debilis Dana, 1852 and Nematopalaemon tenuipes (Henderson, 1893) in Taiwan are confirmed. Three genera, namely Brachycarpus Spence Bate, 1888, Leander Desmarest, 1849 and Leandrites Holthuis, 1950, each with one species are reported for the first time from Taiwan.

The discovery of Euryrhynchidae (Crustacea: Decapoda) in India, with the description of a new genus and species.

A new genus and species of Euryrhynchidae is described from Kerala, India. This freshwater shrimp family was previously only known from northern South America and West Africa. Although the inclusion of the genus in Euryrhynchidae is unequivocal (e.g. shape of the accessory ramus of the antennular flagellum, frontal margin of the carapace, telson ornamentation), the presence of a number of unique characters makes the relative placement of the genus within the family unclear, but likely basal to the other genera. The new genus can be easily distinguished from all others within the family by these characters, e.g. the upper antennular flagellum and its accessory ramus being joined over three divisions, the presence of a reduced carpo-propodal brush and a well-developed branchiostegal groove.

Synalpheus pinkfloydi sp. nov., a new pistol shrimp from the tropical eastern Pacific (Decapoda: Alpheidae).

A new, conspicuously coloured species of the alpheid genus Synalpheus Spence Bate, 1888, is described based on material collected on the Pacific coast of Panama. Synalpheus pinkfloydi sp. nov. is closely related to the western Atlantic S. antillensis Coutière, 1909, the two taxa being transisthmian, cryptic sister species. Both species are characterised by the distal areas of their major and minor chelae coloured in an intense, almost glowing pink-red. The morphological differences between S. pinkfloydi sp. nov. and S. antillensis Coutière, 1909 are subtle, being limited to the slightly different proportions of the merus of both chelipeds, distodorsal armature of the major cheliped merus, relative length of the antennal scaphocerite, and body size. However, they are genetically different with a 10.2% sequence divergence in COI. Based on molecular clock estimates, these transisthmian taxa diverged around 6.8-7.8 mya, i.e. well before the final closure of the Isthmus of Panama 2.5-3 mya.

A new groundwater-dwelling species of Euryrhynchina from Cameroon (Malacostraca, Decapoda, Euryrhynchidae).

A new species of the euryrhynchid shrimp genus Euryrhynchina Powell, 1976, E. puteola sp. nov., is described from Cameroon. The new species can be easily distinguished from the only other species in the genus, E. edingtonae Powell, 1976, by the absence of a setiferous lobe on the eye peduncle, the absence of a meral spine on the ambulatory pereiopods, the shape of the scaphocerite tooth, a single spine on the uropodal diaeresis (vs. 2-3), the absence of a podobranch on the second maxilliped, and the absence of appendices internae on the male pleopods 2-5. Although the species was discovered in a phreatic well, it remains unclear if it is a true stygobiont.

Two new species of the stenopodidean shrimp genus Spongiocaris Bruce & Baba, 1973 (Crustacea: Decapoda: Spongicolidae) from the Indo-West Pacific.

Two new species of the deep-water spongicolid genus Spongiocaris Bruce & Baba, 1973, are described and illustrated from two localities in the Indo-West Pacific. Spongiocaris panglao n. sp. is described on the basis of material from the Bohol Sea, the Philippines, at depths of 220-731 m. Spongiocaris tuerkayi n. sp. is described on the basis of material from Atlantis Bank in the southwestern Indian Ocean at depths of 743-1053 m. Among eight known congeners, both new species appear close to S. semiteres Bruce & Baba, 1973, differing in the rostral length and armature, shape of the carapace, telsonal armature, development of the grooming apparatus of the first pereopod and shape of the third pereopod chela. An identification key to the species currently assigned to Spongiocaris is presented.

A note on the correct spelling of the name of the freshwater shrimp Macrobrachium olfersii (Wiegmann, 1836) (Decapoda, Palaemonidae).

Macrobrachium olfersii (Wiegmann, 1836), popularly known as Pitu, Bristled River Shrimp and Buchura River Prawn, is a freshwater shrimp species widespread along the eastern coasts of the Americas. The species can be found from the southeastern United States, where the prawns were introduced (Holthuis & Provenzano, 1970), southwards to Rio Grande do Sul (Brazil), including numerous records in Mexico, Nicaragua, Costa Rica, Panama, Colombia, Venezuela, Guyana and Suriname (Holthuis, 1952; Williams, 1984; Melo, 2003; Valencia & Campos, 2007).

Description of Alpheus cedrici sp. n., a strikingly coloured snapping shrimp (Crustacea, Decapoda, Alpheidae) from Ascension Island, central Atlantic Ocean.

Alpheus cedricisp. n. is described based on two specimens collected under rocks while scuba diving off the coast of Ascension Island, central Atlantic Ocean. The new species belongs to the Alpheus macrocheles (Hailstone, 1835) species complex and appears to be most closely related to the eastern-central Atlantic Alpheus macrocheles, the western Atlantic Alpheus amblyonyx Chace, 1972, and the eastern Pacific Alpheus bellimanus Lockington, 1877 and Alpheus rectus Kim & Abele, 1988. However, it differs from all these species by a combination of morphological characters and by a diagnostic and striking colour pattern.