A New Species of Amphipod Pariphinotus Kunkel, 1910 (Amphipoda: Phliantidae) from the Southwestern Atlantic.

The genus Pariphinotus Kunkel, 1910 comprises a total of six species around the world, with circumtropical and subtropical distribution, commonly occurring in shallow waters, in soft bottoms and algae, including a previous record of P. seclusus (Shoemaker, 1933) from Brazil. Material examined was collected by SCUBA diving, from rhodolith beds, 12 meters deep, at the Fernando de Noronha Archipelago, off the northeastern Brazilian coast. The new Brazilian species described here can be diagnosed by a unique combination of character states present in other species of the genus. However, it has two exclusive characteristics, distinguishing it from the group: medial apex of pleopod 3 peduncle with two small hook setae, and uropod 1 peduncle not exceeding the apex of telson.

Four new species of Pseudharpinia Schellenberg, 1931 (Crustacea: Amphipoda: Phoxocephalidae) from southwestern Atlantic and new records of P. tupinamba Senna amp; Souza-Filho, 2011.

Four new species of Pseudharpinia Schellenberg, 1931 are described. The material examined was collected during the Mini Biological Trawl project, off Atlantic's southwestern coast on the states of Rio de Janeiro, São Paulo, Santa Catarina and Rio Grande do Sul with rectangular dredges at 25 to 500 meters depth. All the new species described present the following remarkable character states that make them easily distinguishable from their congeners: P. bonhami sp. nov. has pereopod 7 basis with 6 large spines posteroventrally; P. jonesyi sp. nov. exhibits pereopod 6 basis with a long acute spiny-projection posteriorly; P. pagei sp. nov. presents head with ventrolateral lines, antenna 1 primary flagellum with stout article 1, gnathopod 2 palm excavate and with slightly serrate palmar hump; P. planti sp. nov. presents head with dorsal keel and ventrolateral line, elongate flagella article 1 of antenna 1, pereopods 3-4 carpus anterior margin with a comb-like structure distally and pereopod 7 merus strongly produced posteroventrally. An identification key for all species of Pseudharpinia of the world is provided.

Four new species of Lysianassidae Dana, 1849 (Crustacea: Amphipoda) From Northeastern Brazilian coast.

Material collected from three different states of the northeastern region of Brazil (Ceará, Rio Grande do Norte and Bahia) is analyzed. Four new lysianassid species of the genera Aruga and Shoemakerella are described. This paper includes the first record of Aruga in Brazilian waters and an identification key to world species of Aruga and Shoemakerella.

First record of the suborder Colomastigidea (Amphipoda) from Brazilian waters, with description of a new species of Colomastix Grube, 1861.

The suborder Colomastigidea consists essentially of small commensal amphipods and, to the date, no species are known from Brazilian waters. Here, a new species (Colomastix trispinosa sp. nov.) of the genus Colomastix is described from the Northeastern Brazilian coast, Ceará state. The new species is distinguished from the others in the genus especially by the male morphology of the palm of gnathopod 2 and the apex of inner ramus of uropod 1, as well as for the combination of other characters. In addition, it is the first Atlantic species to have a pleated apex on dactylus of female gnathopod 2.

Three new species of Colomastix Grube, 1861 (Amphipoda: Colomastigidea) from Todos-os-Santos Bay, northeastern Brazilian coast, br />with identification keys to Atlantic Ocean species.

Colomastigids are small, commensal marine amphipods distributed worldwide. Here we present descriptions of three new species of Colomastix Grube, 1861 from Todos-os-Santos Bay (Bahia state), and separately identification keys to males and females of all known Colomastix species from the Atlantic Ocean. Males of Colomastix iemanja sp. nov. can be distinguished from all others in the genus especially by the bifurcate apex of inner ramus of uropod 1, with highly asymmetric branches surrounded by a membranous-like structure. Males of Colomastix tubulosa sp. nov. can be distinguished from all others in the genus especially by the tube-like morphology of the apex of inner ramus of uropod 1, the morphology of the distalmost palmar process of gnathopod 2 and by the expanded inner ramus of uropod 2. Females of Colomastix iemanja sp. nov. and Colomastix tubulosa sp. nov. are the only species in the Atlantic with a pleated apex on dactylus of gnathopod 2, besides Colomastix trispinosa Silvany, Alves Senna, 2019. Colomastix marielle sp. nov. can be distinguished from all other species in the genus by the elongate carpus of pereopod 5 of females and by the rudder-like morphology of the apex of inner ramus of uropod 1 of males. These three new species increase the number of Colomastix in the Atlantic from 18 to 21, and are amongst the first records of the suborder Colomastigidea Lowry Myers, 2017 from Brazilian waters.

A new species of Ceradocus Costa, 1853 (Senticaudata: Maeridae) from Ceará State, Northeastern Brazil.

A new species of the genus Ceradocus Costa, 1853 is described from Northeastern Brazil. This species is unique in having: (1) male gnathopod 2 propodus palm ornamented, palmar corner defined by a soft spine; (2) spines along the entire posterior margin of epimeral plate 3, (3) telson with very long apical setae. This new species is the second species of this genus in Brazil. An updated taxonomic key to the Ceradocus of the world is also provided.

Two new species of Cephalophoxoides Gurjanova, 1977 (Crustacea: Amphipoda: Phoxocephalidae) from southeastern Brazil, with comments on the taxonomic status of the genus.

Two new species of the genus Cephalophoxoides Gurjanova, 1977 are described. The material examined was collected during the Mini Biological Trawl (MBT) project, off Brazil's southeastern coast on the states of Rio de Janeiro and São Paulo, at depths ranging from 34 to 75 meters. Cephalophoxoides fortisetus sp. nov. resembles C. homilis (Barnard, 1960) in some general aspects of mandible, propodus of gnathopods 1-2, basis of pereopod 5 and rami of uropod 1. However, it can be distinguished by the latter species mainly by distinct characters on the maxilliped, gnathopod 1, uropod 2 and uropod 3. Also, the new species presents 1 short and 2 long stout setae on the lobes of telson as a notable character. Cephalophoxoides obtusimanus sp. nov. can be distinguished from its congeners by presenting gnathopod 1 with an obtuse and weakly chelate palm as an exclusive character of the genus. An identification key for all species of Cephalophoxoides of the world is provided.

A new species of Stephonyx (Amphipoda, Amphilochida, Lysianassoidea) from Brazil.

A new species of Stephonyx Lowry and Stoddart, 1989 from northeastern Brazil is described, the second record of the genus from Brazil. The new Brazilian species is morphologically close to the type species of the genus. In this paper we compare the different descriptions of Stephonyx biscayensis (Chevreux, 1908) and recommend the necessity of a revision, since some described species may or may not be S. biscayensis.

A new species of Hyalella (Crustacea: Amphipoda: Hyalellidae) from Itatiaia National Park, Brazil: an epigean freshwater amphipod with troglobiotic traits at 2,200 meters of altitude.

A new species of the freshwater amphipod Hyalella Smith, 1874 is described for the plateau of the Itatiaia National Park, located between the states of Minas Gerais and Rio de Janeiro, southeastern Brazil. This is the first Brazilian species of Hyalella found at more than 2,200 meters of altitude. The specimens were found in a small stream, buried under rocks, in the higher area of the Park. The main morphological characteristics that differentiate the new species are the extreme reduction of the size of the uropod 3, absence of apical setae on telson, absence of comb-scales on gnatopods 1 and 2, absence of curved seta on inner ramus of uropod 1 and sternal gills tubular on pereonites 3 to 7. The new species presents similarities with some cave species of the genus, apparently being troglophile and that is the process of adaptation to the hypogean habitat. The importance of creating new protected areas for the conservation of Hyalella in Brazil is discussed.

Four new species of Cymadusa Savigny, 1816 (Amphipoda: Ampithoidae) and new records of C. filosa Savigny, 1816 from Brazilian coast.

Four new species of the genus Cymadusa are described from Brazil (states of Ceará, Espírito Santo and Rio de Janeiro). Cymadusa icapui is described from Ceará state, C. trindadensis is described from Espírito Santo state, C. rasae and C. tartarugae are described from Rio de Janeiro state. Two identification keys are presented: one to all known species of the family Ampithoidae from Brazil, and another one to world species of Cymadusa. Based on literary review and analysis of collection material, we extend the distribution of Cymadusa filosa Savigny, 1816 along the Brazilian coast by finding new location records of the species based on analysis of stored collection material.

On the genus Elasmopus Costa, 1853 from the Northeastern Coast of Brazil with five new species and new records.

The genus Elasmopus is the most diverse in the Family Maeridae. Five new species and new records of Elasmopus from the Brazilian coast are herein described. The specimens were collected in intertidal and subtidal zones along the Northeastern Brazilian coast between 2010 and 2014. The distribution of Elasmopus longipropodus along the coast is extended. Eighteen species of Elasmopus are known from Brazil, not including these five new species. An identification key to the species of Elasmopus is provided.

A new species of Cyphocarididae (Crustacea, Amphipoda, Lysianassoidea) from off the northeastern Brazilian coast.

This paper describes a species of the genus Cyphocaris Boeck, 1871, the first record of the family Cyphocarididae Lowry & Stoddart, 1997 from Brazil. Two specimens, both females, were found in the stomach contents of a tuna caught in the Saint Peter and Saint Paul Archipelago. The new species is characterized by coxae 4 and 5 both large, coxa 4 partially overlapping coxae 2-3; coxa of pereopod 5 with ventral laminar projection and well-developed anteroventral lobe, broadly rounded and apically folded backwards, basis with anterior margin broadly rounded and posterior margin with large subacute naked projection (or spur); uropod 3, outer ramus paddle-shaped; and telson elongate and deeply cleft, with a nail.

New record of the genus Peramphithoe Conlan & Bousfield, 1982 (Amphipoda: Ampithoidae) from Brazilian coast, with description of a new species.

A new species Peramphithoe conlanae sp. nov. is described from Todos os Santos Bay, Bahia, Northeast Brazil. The new species is characterized by the morphology of male gnathopod 1 coxa with anteroventral corner acute, palm transverse bearing a robust seta on the palmar corner and dactylus 2 × palm length, gnathopod 2 with propodus oval, palm extremely acute, concave and lacking processes or robust setae, pereopods 5 and 6 with merus and carpus inflated. This paper increases the number of described species in the genus to 22. It is the first record of the genus Peramphithoe from Brazilian waters.

Amphibious shelter-builder Oniscidea species from the New World with description of a new subfamily, a new genus and a new species from Brazilian cave (Isopoda, Synocheta, Styloniscidae).

The new subfamily Iuiuniscinae, Styloniscidae, is erected for the new genus Iuiuniscus and the new species I. iuiuensis, which is described from cave of the State of Bahia, Northeastern Brazil. A special ecological character is shown here for the first time for a New World Oniscidea: the construction of mud shelters. An introduction addressing the systematics of Synocheta with emphasis on Styloniscidae Vandel, 1952 is provided, as well as general comments about the dependence of water in some Oniscidea and ecological traits of amphibious Synocheta. The problems referring to nomenclature, taxonomy and the interrelationships in Styloniscidae are discussed.

A new species of Boca Lowry & Stoddart, 1997 (Amphipoda: Lysianassoidea: Aristiidae) from a mesophotic coral ecosystem off Puerto Rico, Caribbean Sea.

A new species of the genus Boca Lowry & Stoddart, 1997 is described from a mesophotic coral ecosystem off southwestern Puerto Rico, in the Caribbean Sea. The new species is easily recognized from the others in the genus mainly by the following characters: (1) maxilliped, inner plate with 2 long apical simple setae; palp, articles slender, subequal in length; (2) gnathopod 1, propodus slightly elongate, about 2.5 × longer than wide, and palm extremely acute, quite long and distinctly demarked by a robust seta at the palmar corner; (3) gnathopod 2, carpus slightly elongate, about 3.7 × longer than wide; (4) pereopod 5, basis widely expanded posteriorly, posterior margin rounded and smooth, and posteroventral lobe weakly developed. We also present a key to world species of Boca. This is the fifth species of Boca from world's oceans and the first record of the genus from Puerto Rico.

Spelaeogammarus titan, a new troglobitic amphipod from Brazil (Amphipoda: Bogidielloidea: Artesiidae).

A new troglobitic species of the amphipod family Artesiidae Holsinger, 1980 is described from a cave in the municipality of Santa Maria da Vitória, in the Brazilian state of Bahia, northeastern Brazil. Spelaeogammarus titan sp. nov. differs from the others in the genus by its body length, rising up to 18.3 mm, the antenna 1 with accessory flagellum 6-articulate, propodus of the first gnathopod 1.8 X longer than basis, the largest in the genus, coxa 5 with posterior lobe slightly concave, inner ramus of pleopods with 10 to 13 setae, outer ramus of uropod 3 with 22 simple setae, and telson with 1 apical plus 3 subapical stout setae in each lobe. With this study, the knowledge of Spelaeogammarus is improved to 5 species, all of them exclusive to caves in the northeastern Brazilian state of Bahia. A comparative table with the diagnostic characters of the species of Spelaeogammarus is provided.

A new species of the genus Dulichiella Stout, 1912 (Crustacea: Amphipoda: Melitidae) from Pecém Harbor, Ceará state, Brazil.

A new species of the genus Dulichiella Stout, 1912 is described for the Northeastern Brazilian coast. The new species is recognized from the others in the genus by presenting (1) the accessory flagellum 5-articulate, (2) distolateral crown of gnathopod 2 of males with 4 spines, (3) Maxilla 1 inner plate, outer plate and palp distally enlarged and rounded, and (4) Pereopods 6 and 7 without bunches of long setae. This is the second species of Dulichiella recorded from South Atlantic and Brazilian waters.

A new species and first record of the genus Shoemakerella Pirlot, 1936 (Crustacea: Amphipoda: Lysianassidae) from Brazil.

A new species of the genus Shoemakerella Pirlot, 1936 is described for the Southeastern Brazilian continental shelf. The new species is easily recognized from the others in the genus mainly by the shape of the gnathopod 2. This is the first species of Shoemakerella from Brazilian waters.

Description of a new genus and species of the family Melphidippidae Stebbing, 1899 (Crustacea: Amphipoda) from the deep waters of Brazil.

The species of the amphipod family Melphidippidae are distributed worldwide in marine habitats, but there is no record of this family from Brazil so far. A new genus and species of Melphidippidae are described from Brazilian waters. Stebbingiella gen. nov. is monotypic and is distinguished from the other genera of the family by the presence of: antenna 1 with accessory flagellum 7-articulate, lateral cephalic lobe subacute, with globular eyes extremely produced, reaching beyond the second article of peduncle of antenna 2; gnathopods stout and slightly subchelate; coxae 3 and 4 with strong anterior projection and coxae 5 and 7 with strong posterior projection; telson cleft, not fully movable, with two globular lobes, about 2X wider than long. Stebbingiella globulosa sp. nov. is the first species of Melphidippidae recorded from Brazilian waters.

A new species of Elasmopus (Amphipoda: Hadzioidea: Maeridae) from Suape Harbor, Northeastern Brazilian coast

A new amphipod species of the genus Elasmopus Costa, 1853 is described based on material collected from intertidal rocky shore, near the Suape Harbor, coast of the Brazilian state of Pernambuco. The new species may be recognized by the propodus of gnathopod 2 suboval, slightly tapering distally, palmar margin not defined by a stout seta, spine, or palmar corner, with a subdistal blunt tubercle, posterior margin covered by a dense fringe of plumose setae, and posterior margin of basis of pereopod 7 castelloserrate. This is the ninety-fifth species of the genus Elasmopus described worldwide, the most diverse genus in the family Maeridae Krapp-Schickel, 2008, and the eighth species recorded from Brazilian waters. An identification key to Brazilian species of Elasmopusis also provided.

Uma nova espécie Amphipoda do gênero Elasmopus Costa, 1853 é descrita com base em material coletado da zona entre marés de um costão rochoso, próximo ao Porto de Suape, costado estado brasileiro de Pernambuco. A nova espécie pode ser reconhecida pelo própodo do gnatópo de 2 suboval, estreitando-se de forma suave distalmente, margem palmar não definida por uma cerda grossa, espinho, ou ângulo palmar, comum tubérculo subdistal não agudo, margem posterior coberta por uma franja densa de cerdas plumosas, e margem posterior da base do pereópodo 7 castelosserrado. Esta é a nonagésima quinta espécie do gênero Elasmopus descrita ao redor do mundo, o mais diverso gênero na família Maeridae Krapp-Schickel, 2008, e a oitava espécie registrada para as águas brasileiras. É fornecida também uma chave de identificação para as espécies brasileiras de Elasmopus.