Three new species of Hyalella (Crustacea: Amphipoda: Hyalellidae) from the Southern Brazilian Coastal Plain

In this study, three new species of Hyalella (Crustacea: Amphipoda: Hyalellidae) are described based on specimens collected in wetlands located in three freshwater ecoregions (Southeastern Mata Atlântica, Tramandaí-Mampituba and Laguna dos Patos) of the southern Brazilian Coastal Plain (states of Rio Grande do Sul and Santa Catarina). Hyalella minuana n. sp. was recorded in the southernmost region of the state of Rio Grande do Sul. This species is characterized by presenting smooth body surface, epimeral plates not acuminated, nine serrate setae on the inner face of gnathopod 1, and peduncle of uropod 3 with four cuspidate setae with accessory seta and without plumose seta on the margin of the telson. Hyalella lagoana n. sp. was recorded in the northern region of Rio Grande do Sul and southern region of Santa Catarina. This species shows body surface smooth, epimeral plates not acuminated, nine serrate setae on the inner face of gnathopod 1, peduncle of uropod 3 with five cuspidate setae with accessory seta, and telson with six cuspidate setae with accessory seta without plumose seta on the margins. Hyalella sambaqui n. sp. was recorded in the state of Santa Catarina. This species is characterized by presenting smooth body surface, epimeral plates not acuminated, six serrate setae on the inner face of gnathopod 1, peduncle of uropod 3 with three cuspidate setae with accessory seta, and telson with three cuspidate setae with accessory seta and four plumose setae on the margin of the telson. The new records elevates the known diversity of species of Hyalella in the Brazilian territory to 33 species (19 in the southern Brazilian region) and to 83 species in the Americas.

A new species of Stygiopontius (Copepoda, Siphonostomatoida, Dirivultidae) from a deep-sea cold seep in the South China Sea

A new species of the copepod genus Stygiopontius is described based on samples from a cold seep in northeastern South China Sea southwest to Taiwan, which were collected by the ROV Faxian with its mother vessel R/V Kexue in September 2017. The copepods were obtained by washing Shinkaia crosnieri Baba & Williams, 1998 (Decapoda: Munidopsidae) caught at a depth of 1124 m. The new species can be distinguished from its congeners by the combination of the following characteristics: caudal rami about 3.5 times as long as wide; basis of maxilliped with plumose seta, endopodal claw of maxilliped stout, with a row of fine spinules on inner margin; coxa of leg 1 with one inner seta; basis of leg 1 with stout spine exceeding to end of first endopodal segment; second endopodal segment of female leg 4 with pointed process; third exopodal segment of leg 4 with three outer spines. This is the first record of a Stygiopontius species from a cold seep.

Three new species of the genus Bodotria (Crustacea: Cumacea: Bodotriidae) from the Yellow Sea in Korea

Three new species of Cumacea belonging to the genus Bodotria were collected from the Yellow Sea in Korea. Among them, Bodotria (Bodotria) hwanghaensis sp. nov. and Bodotria (Bodotria) pseudomaculosa sp. nov. share the dorso-lateral carina on the carapace and uniarticulated uropod endopod with other Korean Bodotria species. In contrast, the last one, Bodotria (Atlantobodotria) incarinata sp. nov. lacks the dorso-lateral carina on the carapace and has a biarticulated uropod endopod. The new species B. (A.) incarinata sp. nov. can be distinguished from all other Bodotria species by the combination of carapace without dorso-lateral carina or ridge, dorso-median carina marked over whole length of carapace, antero-lateral corner of carapace rounded, antennal notch shallow, maxilliped 3 merus and carpus dilated, pereopod 1 carpus not dilated, and pereopod 2 basis with plumose seta. The new species B. (B.) hwanghaensis sp. nov. can be distinguished from all other Bodotria species by the combination of carapace almost ovoid in dorsal view, carapace lower edge of mid-lateral depression forming a faint ridge, pereopod 1 carpus not dilated, and pereopod 2 basis without plumose seta. The new species B. (B.) pseudomaculosa sp. nov. can be distinguished from all other Bodotria species by the combination of carapace surface covered with coarse squamosa-reticulate patterning formed by large, shallow pits, carapace lower edge of mid-lateral depression forming an angular ridge, pereopod 1 carpus little dilated, and pereopod 2 basis with plumose seta. We described with full illustrations, including mouthparts for the three new species. Also, a key to the Korean Bodotria species is provided.

Description of the first zoeal stage of Synalpheus apioceros Coutière, 1909 (Caridea: Alpheidae), including a comparative analysis with larval morphology from the genus Synalpheus Spence Bate, 1888

Herein, the Zoea I of Synalpheus apioceros is described, followed by a comparative analysis of the first larval stage from Synalpheus. Larvae were obtained from two ovigerous females sampled in Ubatuba, São Paulo. The morphology of the Zoea I of S. apioceros was compared to five other Synalpheus species whose structures were previously described: S. biunguiculatus, S. minus, S. neomeris, S. pectiniger, and S. tumidomanus. A set of unique morphological characteristics was found for S. apioceros: exopod of antennule with 4 aesthetascs and 1 plumose seta; coxal endite of maxillule with 2 simple setae plus 2 plumose setae; basial endite of maxillule with 2 simple setae plus 2 short spines; endopod of maxillule with 1 plumose seta plus 2 simple setae; basial endite of maxilla bilobed with 2 (1 plumose and 1 simple) + 2 (1 plumose and 1 simple) setae; coxal endite of maxilla bilobed with 2 + 1 plumose setae; endopod of maxilla with 3 (1 plumose and 2 simple) terminal setae + 2 simple setae; endopod of first maxilliped unsegmented with 3 terminal simple setae; basis of first maxilliped with 5 spines; endopod of second maxilliped 5-segmented with 0, 0, 0, 1 plumodenticulate, 4 (1 serrate + 3 simple) setae; endopod of third maxilliped 5-segmented with 0, 0, 0, 1 simple, 3 simple setae; pereiopods 1st to 3rd birramous and 4th and 5th uniramous. S. apioceros shows higher morphological similarity with S. minus, followed by S. tumidomanus, S. neomeris and S. pectiniger, probably since these species present extended larval development. Besides the similar morphology among species, the unique attributes presented here are important for the genus’ taxonomy, being fundamental for identifying the first larval stages of Synalpheus, as well as for subsidizing information for species identification keys.

Two Hexapleomera species from Japan, with a new species description and discussion of phylogenetic relationships within Hexapleomera (Crustacea: Tanaidacea)

We describe Hexapleomera sasuke sp. nov. and provide a supplemental redescription of Hexapleomera urashima Tanabe et al., both of which are based on specimens collected in Japan. Hexapleomera sasuke closely resembles H. urashima, sharing a uropod with four articles, maxillipedal endites with two tiny dorso-subdistal and two distal spiniform setae, a labium with the palp fused to the outer lobe, and the pereopod-1 propodus with an inner subdistal plumose seta. The new species differs from H. urashima in having the basal article of pleopod 3 with three outer plumose setae, the chelipedal carpus with three or four dorsodistal simple setae, the region between the bases of the chelipedal dactylus and fixed finger with three or four simple setae, and deeply pigmented pleopodal rami. We determined partial sequences of the cytochrome c oxidase subunit I (COI) gene (655 nt) from H. sasuke, which proved to be 15.0–15.3% divergent from H. urashima in Kimura 2-parameter (K2P) distance; also in partial sequences of 18S rRNA gene (1888 nt after alignment), 0.8% divergent (K2P distance) was detected between two species. Based on morphology and molecular data, we discuss phylogenetic relationships within Hexapleomera, and propose two morphologically distinct groups, the robusta group and the wombat group.

A new species of Aciconula (Amphipoda, Senticauda, Caprellidae) from Sultan Iskandar Marine Park, Malaysia

A new species of caprellid, Aciconulatinggiensis (Amphipoda, Senticaudata, Caprellidae) was discovered from Pulau Tinggi, Sultan Iskandar Marine Park (SIMP), South China Sea, Malaysia. The new Malaysian species can be distinguished from the other Aciconula species by the combination of the following characters: 1. the presence of a very small suture between head and pereonite 1; 2. antenna 1 flagellum with 4 articles; 3. inner lobe of lower lip unilobed; 4. gnathopod 2 palm of propodus with a large proximal projection (stretching from the proximal margin of the palm to nearly mid-way of palm); 5. pereopods 3–4 with 2 articles (article 1 subrectangular, article 2 conical or tapering at the tip with 1 plumose seta and 2 normal setae) and; 6. pereopod 5 covered with relatively dense and long setae. An updated identification key for the five known species in the genus, including information on the respective geographical distribution and habitat, is presented.

First record of the family Sphyrapodidae Guţu, 1980 (Crustacea: Peracarida: Apseudomorpha) with the description of a new species ofSphyrapusfrom the Colombian Caribbean

A new sphyrapodid tanaidacean,Sphyrapus caribensissp. nov. is described and a new record ofKudinopasternakia siegiis reported for the Colombian Caribbean based on samples collected during cruises in 2014–2015. The new species appears to be most closely related to the northeast Atlantic species,Sphyrapus malleolus. Sphyrapus caribensiscan be distinguished fromSphyrapus malleolusby a combination of characters, including the maxillipedal basis without long distal seta, the number of setae on the distoventral margin of pereopods 1 and 2, and the number of plumose seta on the pleopod basis. A key for the separation ofSphyrapusspecies is presented.

Morphological description of early zoeal stages of Alpheus brasileiro Anker, 2012 reared in the laboratory, including a revision of the larval morphology of the first zoeal stage of the genus Alpheus Fabricius, 1798 (Caridea: Alpheidae)

The aims of this study were to describe and illustrate the early larval stages of the snapping shrimp Alpheus brasileiro Anker, 2012 and to review the larval morphology (Zoea I) of the genus Alpheus Fabricius, 1798. Larvae were obtained from two females with embryos collected in an intertidal estuary in Cananéia, São Paulo state, Brazil. The published descriptions of all available Alpheus zoea I (only 14 spp., 4.7%) were used for a comparison of larval morphology. The zoeae I of Alpheus species are very similar, but A. brasileiro can be separated from the other studied species by the following set of characteristics: antennal scale 5-segmented with 11 plumose setae and 2 simple setae; coxal endite of maxillule with 3 simple setae and 2 sparsely plumose setae; and coxal endite of maxilla with 1 simple seta and 1 sparsely plumose seta. The description of early larval development of A. brasileiro indicates consistent characteristics, which, when analyzed along with other morphological, molecular, and biogeographical aspects, can help to elucidate the complex phylogenetic relationships between the species in the group. However, this is the first zoeal description of a member of Alpheus armillatus species complex and it therefore does not permit a comparison. Only with new additional descriptions we will be able to generate a clearer scenario in this field due the high similarity among the species.

Coboldus chazaroi, a new species of iphimediid amphipod (Amphipoda, Gammaridea, Iphimediidae) from a submarine cave, north Cuba

The amphipods of Coboldus are considered as antipolar members of iphimediids with loss of a maxilla 1 palp article 2. Anew amphipod species of the genus Coboldus (Family Iphimediidae) collected from soft bottom in a submarine cave,Northern Cuba, is described. Coboldus chazaroi sp. nov., differs from all other known species by the following characters:pereonal dorsal processes bifid and equal in length, coxa 1 ventrally acute and bifid, article 5 of gnathopod 2 longer than6, dactylus longer than palm, posterior margin of pleonal epimeron 3 with 3 teeth, mandibular palp article 2 with 1 subdistal plumose seta, molar poorly developed with 1 basal seta, lacinia mobilis rectangular and finely serrate.

New species and new records of cumaceans (Crustacea: Peracarida: Cumacea) from the Andaman Islands, Indian Ocean

This paper describes a collection of Cumaceans from intertidal macroalgae on the shores of the Andaman Islands containing two new species viz. Bodotria andamanensis sp. nov. of the family Bodotriidae, Gynodiastylis bacescui sp. nov. of the family Gynodiastylidae and five species of the family Nannastacidae of which three species viz. Cumella forficuloides Băcescu & Muradian, 1975, Nannastacus goniatus Gamô, 1962 and Scherocumella nichollsi Hale, 1945 are recorded for the first time from India. Bodotria andamanensis sp. nov. is characterized by having two large visual elements, the first segment of the pereon hardly visible dorsally, maxilliped 3 with robust articles, a short uropod, rami with two articles; Gynodiastylis bacescui sp. nov. is characterized by an elongated carapace, a rounded and large telson, reaching half of the length of the uropodal peduncle, the basis of maxilliped 3 with a short outer plumose seta, and a uropodal endopod with three articles.