Morphology and DNA Data Reveal a New Shrimp Species of Genus Latreutes Stimpson, 1860 (Decapoda: Hippolytidae) from the Western Atlantic.

The genus Latreutes Stimpson, 1860 comprises 17 described species of marine shrimps, most of them distributed in the Indo-West Pacific and eastern Pacific. Only three species are recorded in the Atlantic. When comparing specimens of Latreutes parvulus (Stimpson, 1871) from both sides of the Atlantic by means of a combination of morphological and molecular data, we recognized a new species of Latreutes from Brazil (Rio Grande do Norte, Bahia, Rio de Janeiro and São Paulo). The phylogenetic tree generated on the basis of the 16S gene showed a clear separation of the specimens of the new species from the other closely related species analyzed. The analyses also evidenced that the new species and L. parvulus are sister taxa. Although very similar, both species can be easily separated by features of the scaphocerite and eyestalk. Rostrum form and dentition, characters usually used for L. parvulus recognition, were highly variable in both species. Thus, herein the new species is described, illustrated, and compared with morphological similar species of Latreutes. A key for the Atlantic species is also provided.

Description of Alpheus buckupi spec. nov., a new amphi-Atlantic snapping shrimp (Caridea: Alpheidae), based on morphological and molecular data.

A new amphi-Atlantic snapping shrimp of the genus Alpheus Fabricius, 1798, Alpheus buckupi spec. nov., is described and illustrated based on material collected from the western (Orinoco Delta, Venezuela to São Paulo, Brazil) and eastern Atlantic (São Tomé and Príncipe). The new species is morphologically similar to members of the A. lobidens De Haan, 1850 species complex, from the Indo-Pacific, including A. inopinatus Holthuis & Gottlieb, 1958 from the eastern Mediterranean, and the Red Sea to Pakistan, especially based on major and minor chelae configuration. We also characterized this new species in terms of DNA sequences of a ribosomal 16S subunit and compared it in a phylogenetic context. These analyses showed a clear separation of the specimens of A. buckupi spec. nov. from similar species of the A. edwardsii (Audouin, 1826) species group, including some morphologically close species such as A. cf. lobidens, A. heterochaelis Say, 1818, A. pontederiae de Rochebrune, 1883, A. sp. aff. euphrosyne De Man, 1897, and A. microrhynchus De Man, 1897.

First zoeal stage of the partner shrimp Periclimenes paivai Chace, with remarks on the genus Periclimenes O.G. Costa (Caridea, Palaemonidae.

The morphology of the first zoeal stage of Periclimenes paivai Chace is described and illustrated for the first time. Larvae were obtained from three females with embryos, caught in the type locality (Cananéia, São Paulo state, Brazil). The morphological characters are detailed and compared with all previous descriptions of larvae in the genus (P. amethysteus, P. brevicarpalis, P. diversipes, P. pandionis, P. sagittifer and P. soror). The zoeae I of Periclimenes species are very similar, but P. paivai can be separated from the other six species by means of five characteristics: 8 plumose setae on the inner margin of the antennal scale, one spine on the endopod of the maxillule, one cuspidate seta on the basal endite of the maxilulle, one plumose seta on the single coxal endite of the maxilla, and one plumose seta on the endopod of the maxilla. Remarks from a comparative analysis of available descriptions of the genus are furnished. 

Molecular analyses reveal two lineages under the name Rimapenaeus constrictus (Stimpson, 1874) (Decapoda, Dendrobranchiata, Penaeidae).

The genus Rimapenaeus Prez Farfante Kensley, 1997 occurs in shallow waters and includes six species, being four restricted to Pacific Ocean and two restricted to Atlantic Ocean. Along the Brazilian coast, Rimapenaeus constrictus (Stimpson, 1874) (called camaro ferrinho in Brazil) is one of the species most often accidentally caught during fishery activities, but due to its small size and abundance, it is not commercially exploited. Considering its wide distribution in the western Atlantic the purpose of this study was to examine from a molecular and morphological perspective specimens identified as R. constrictus sampled at the two extremes of its distribution (USA and southeastern Brazil). The phylogenetic trees (16S mtDNA and Cytochrome oxidase subunit I genes) showed a split of these specimens in two well-supported lineages: lineage A from USA (Maryland, Virginia, Florida and Gulf of Mexico) and lineage B from southeastern Brazil (Rio de Janeiro and So Paulo). The genetic distance observed between them (16S: 3.2%; COI: 9.4%) is high to be intraspecific, mainly when compared with other Dendrobranchiata studied. Instead of it none clear pattern that allows the morphological separation of these lineages was observed. We conclude that the shrimps usually called of Rimapenaeus constrictus, widely distributed in the Atlantic, actually represents two species and the Brazilian lineage probably is a new species, not described yet.

Checklist of decapod crustaceans from the coast of the So Paulo state (Brazil) supported by integrative molecular and morphological data: V. Dendrobranchiata and Pleocyemata [Achelata, Astacidea, Axiidea, Caridea (Alpheoidea and Processoidea excluded), Gebiidea, Stenopodidea].

This checklist is the fifth and last compilation on the decapod crustaceans reported to So Paulo (Brazil) coastal area, resulting from long-term multidisciplinary projects, which combined morphological analyses and molecular techniques. The current research includes 75 decapod species, herein referred as shrimps/lobsters-like (shrimps, ghost-shrimps, lobsters, and related groups), reported to So Paulo coastal area. These species occur in marine, estuarine, and amphidromous habitats and are classified into 21 families as follow: Aristeidae (2 spp., 2 genera), Atyidae (4 spp., 2 genera), Axianassidae (1 sp., 1 genus), Callianassidae (1 sp., 1 genus), Callichiridae (6 spp., 4 genera), Crangonidae (1 sp., 1 genus), Glyphocrangonidae (1 sp., 1 genus), Luciferidae (2 spp., 2 genera), Nephropidae (4 spp., 2 genera), Palaemonidae (15 spp., 9 genera), Palinuridae (2 spp., 1 genus), Pandalidae (1 sp., 1 genus), Pasiphaeidae (1 sp., 1 genus), Penaeidae (10 spp., 6 genera), Sergestidae (3 spp., 3 genera), Sicyoniidae (4 spp., 1 genus), Scyllaridae (5 spp., 3 genera), Solenoceridae (4 spp., 3 genera), Stenopodidae (2 spp., 1 genus), and Upogebiidae (6 spp., 1 genus). We generated new sequences of cytochrome oxidase subunit I (barcode region) and 16S genes (51 and 54, respectively) of 54 species. Our examination concluded that 75 shrimps/lobsters-like species are reported to the So Paulo coast. We excluded Leander tenuicornis (Palaemonidae), Penaeus setiferus (Penaeidae), Philocheras gorei (Crangonidae), and Rhynchocinetes typus (Rhynchocinetidae) from this list.

Checklist of decapod crustaceans from the coast of the São Paulo state (Brazil) supported by integrative molecular and morphological data: IV. Infraorder Anomura: Superfamilies Chirostyloidea, Galatheoidea, Hippoidea and Paguroidea.

This checklist is the fourth contribution resulting from a long-term multidisciplinary project which combined morphological analyses and molecular techniques (mitochondrial DNA markers) for accurate identification of marine and coastal decapod crustaceans of São Paulo State (Brazil). We provide a list of 63 species of the following 11 families of 4 superfamilies of Anomura: Albuneidae (4 spp.), Blepharipodidae (1 sp.), Chirostylidae (1 sp.), Diogenidae (18 spp.), Hippidae (1 sp.), Munididae (8 spp.), Munidopsidae (1 sp.), Paguridae (13 spp.), Parapaguridae (2 spp.), Porcellanidae (13 spp.), and Pylochelidae (1 sp.). Seven species previously reported from the region were neither collected nor found in museum collections during our study, including one (Sympagurus dimorphus) that we suggest to be removed from São Paulo coast fauna lists. We generated new sequences of cytochrome oxidase subunit I (barcode region) and 16S genes of 44 species. This anomuran inventory may serve as guideline for future studies on taxonomy, conservation, population genetics, biogeography, and phylogenetics, which might flag species that deserve further investigations and concerns.

First zoeal stage of the snapping shrimps Alpheus formosus Gibbes, 1850 and Alpheus malleator Dana, 1852 (Caridea: Alpheidae), with new characters to the genus.

The first zoeae of Alpheus formosus Gibbes, 1850 and Alpheus malleator Dana, 1852 are described and illustrated for the first time, based on laboratory-hatched larvae from parental females sampled in Vitória Island, Ubatuba, Brazil. Both species shared many characters with other species of genus Alpheus Fabricius, 1798, but they also have some exclusive characters as 10 setae on the basis of the maxilla, first maxilliped with endopod 2-segmented and exopod 4-segmented, second maxilliped with exopod 4-segmented, presence of bud only of the first pereopod, presence of anal spine and simple dorsal setae on the pleon. The zoea I of both species, nevertheless, can be separated by segmentation in the exopod of the antenna (8 in A. formosus, 6 in A. malleator); segmentation in the endopod and exopod of the third maxilliped (5 in A. formosus and 4 in A. malleator); peduncle of antennule 3-segmented in A. formosus (unsegmented or 2-segmented in other species) and presence of a medial tubercle in the proximal segment in the exopod of the antenna of A. malleator (absent in A. formosus, not reported in all other species). In this study three new characters are proposed to be analyzed in zoea of the genus Alpheus: presence of anal spine in both species (absent in Alpheus saxidomus Holthuis, 1980, but not reported in other species) and for the first time reported, presence of a tubercle in the exopod of the antenna (present only in A. malleator) and presence of simple dorsal setae on the pleon (both species), here analyzed under light and scanning electron microscopy.

Validation of Xiphopenaeus dincao Carvalho-Batista, Terossi, Zara, Mantelatto amp; Costa and Xiphopenaeus baueri Carvalho-Batista, Terossi, Zara, Mantelatto amp; Costa (Decapoda: Penaeidae) from western Atlantic.

Two species of Penaeidae shrimp from western Atlantic were described by Carvalho-Batista et al. (2019) as Xiphopenaeus dincao and Xiphopenaeus baueri. The descriptions and figures presented by Carvalho-Batista et al. (2019) and the posterior author's correction (Carvalho-Batista et al., 2020) characterize the species. However, the journal issue in which the description was published is online only, and the article with the new names did not include a Zoobank registration number (LSID), required for validation of new names in electronic-only publications (ICZN 2012). Thus, the names Xiphopenaeus dincao and Xiphopenaeus baueri, as published in Scientific Reports 9: 15281, is not available according the International Code of Zoological Nomenclature (ICZN 1999, 2012). Therefore, the present note serves to validate the names Xiphopenaeus dincao and Xiphopenaeus baueri by fulfilling ICZN conditions for nomenclatural availability. Type specimens of both species are deposited in Museu de Zoologia da Universidade de São Paulo (MZUSP), São Paulo, Brazil.

Delimiting the snapping shrimp Alpheus lobidens De Haan, 1849 (Caridea: Alpheidae) based on morphological and molecular data.

Our aim was to delimit the taxonomic status of the snapping shrimp Alpheus lobidens De Haan, 1849, based on morphological and molecular analyses of the topotype material from Nagasaki (Japan). We provide a redescription, detailed illustrations, and molecular data. Through comparisons with close-related species, we also tested the taxonomic status of A. inopinatus Holthuis Gottlieb, 1958 and A. buckupi Almeida, Terossi, Araújo-Silva Mantelatto, 2013. We examined 74 specimens previously identified as A. lobidens, 84 specimens of A. buckupi, and 30 of A. inopinatus. The morphological analysis was based on the examination of 68 characters. The molecular analysis included mitochondrial gene sequences (16S) of 18 individuals: six A. lobidens, three A. buckupi, one A. inopinatus, and eight individuals of other species of Alpheidae. The morphological analysis revealed that A. lobidens sensu stricto is consistently distinct of A. lobidens sensu lato, A. inopinatus and A. buckupi. The genetic analyzes (Bayesian Inference and p-distance) corroborated the morphological results and showed a clear separation between them. The highest values of genetic divergence (p-distance) (19%) were observed between A. lobidens sensu stricto and A. buckupi, and between A. lobidens sensu stricto and A. lobidens sensu lato from Australia (Northern Territory). The lowest divergence (12%) occurred between A. lobidens sensu stricto and A. lobidens sensu lato from Marshall Islands. Based on our results, the occurrence of A. lobidens sensu stricto is currently restricted to the type locality in Japan, and A. inopinatus and A. buckupi are valid taxa. Delimiting A. lobidens sensu stricto is relevant since the name A. lobidens has been applied to cryptic species, resulting in a high unclear taxonomic state.

Author Correction: A multigene and morphological analysis expands the diversity of the seabod shrimp Xiphopenaeus Smith, 1869 (Decapoda: Penaeidae), with descriptions of two new species.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Checklist of decapod crustaceans from the coast of the São Paulo state (Brazil) supported by integrative molecular and morphological data: III. Infraorder Brachyura Latreille, 1802.

This checklist is the third part of a series derived from a long-term multidisciplinary project on the biodiversity of decapod crustaceans from marine and coastal environments of São Paulo state (Brazil). We integrated molecular techniques (DNA markers) and morphological analyses of adult specimens for accurate identifications. We compilated 185 species from the literature, but we confirmed the presence of 168 species: 130 of which we sampled, analyzed and obtained sequences (COI and/or 16S totalizing 113 sequences) and 38 that were not directly collected but were confirmed by analyses. In addition, 27 had their distribution removed from São Paulo due to uncertainties, and absence of material as voucher. Five species were reported for the first time on the coast of São Paulo (Calappa ocellata, Neohelice granulata, Teleophrys pococki, Teramnonotus monodi, Tetraxanthus rathbunae) and one on the Brazilian coast (Pseudomedaeus agassizi). Most of the non-sampled species previously reported on the coast of São Paulo might be considered doubtful records stablished in the past by inaccurate analyses, which assumed extended distribution to the area and/or misidentifications. At this time and based on our refined compilation, we can estimate the brachyuran diversity on the coast of São Paulo in 168 species. This detailed inventory contributes to the knowledge on the local decapod fauna by checking available dataset, adding new species records in São Paulo and new sequences to GenBank database. These data may serve as baseline for future identifications and studies on conservation, population genetics, biogeography and phylogenetics, which might flag species that deserve further investigations and concerns.

Taxonomic status of the amphi-Atlantic species Plesionika acanthonotus (Caridea: Pandalidae): a multi-locus and morphological approach.

Deep-sea shrimps of the species Plesionika acanthonotus (Smith, 1882) and P. holthuisi Crosnier Forest, 1968 are morphologically similar and exhibit overlapping amphi-Atlantic distributions. In the literature, through morphological studies, there are reports of doubts about the validity of P. holthuisi and some authors believe that the eastern and western Atlantic populations of P. acanthonothus could represent two distinct species. The objective of the present study was to use molecular data to elucidate the taxonomic status of the two populations of P. acanthonothus. DNA sequences of two mitochondrial genes (16S rDNA and Cytochrome Oxidase subunit I) and a nuclear gene (Histone 3) were obtained for both species and for both populations of P. acanthonotus. The sequences were also obtained from Genbank for comparison. The trees (separate and multi-locus/partitioned genes) were generated by Bayesian Inference analyzes, and genetic divergence (Kimura-2-parameters) was also calculated. All specimens that had their DNA sequenced were examined morphologically to confirm their identification; morphological variations were noted. The genetic data showed that Plesionika holthuisi is closely related to P. acanthonotus, but clearly separated, indicating that P. holthuisi is a valid species. In the multi-locus analysis, the P. acanthonothus specimens were divided into two clades, one with the eastern Atlantic specimens and another with the western Atlantic specimens. However, this genetic separation was considered to be a population structuring for three reasons: (1) the genetic divergences of the two mitochondrial genes between these two groups (eastern Atlantic X western Atlantic) were smaller than the interspecific divergence for Plesionika; (2) the P. acanthonothus sequences of the Histone 3 gene showed no genetic variation; (3) in the analyzed individuals, no valid morphological character was found to support this separation. Thus, the conclusion of this study is that P. holthuisi probably is a valid species and P. acanthonothus presents two populations with mitochondrial divergences that could be in the process of speciation, but which currently represent only one species.

Congruence between morphology and molecular data supports the distinction between the snapping shrimps Alpheus macrocheles and A. amblyonyx (Caridea, Alpheidae).

The snapping shrimp Alpheus macrocheles (Hailstone, 1835b) is widely distributed across the Atlantic Ocean and was originally described from Hastings, England, based on a very brief description with limited morphological details and diagnostic illustrations. The morphologically similar A. amblyonyx Chace, 1972, type locality Quintana Roo, Mexico, is a western Atlantic taxon. The superficial description of A. macrocheles by Hailstone and the high similarity with A. amblyonyx has led to taxonomic confusion regarding the precise identification of these species. Thus, our objective was to reexamine these two species, based on a combined analysis of morphological-including a redescription for A. macrocheles and new morphological characterization of A. amblyonyx-and molecular data. In total, 42 morphological characters were analyzed, in addition to a phylogenetic analysis of 16S ribosomal RNA (rRNA) gene sequences. A Bayesian Inference analysis recovered A. macrocheles and A. amblyonyx as distinct clades supporting the taxonomic distinction between them. The tree topology suggests that A. macrocheles is more closely related to A. crockeri (Armstrong, 1941) and A. puapeba (Christoffersen, 1979) than to A. amblyonyx, which forms the sister group to a well-supported clade containing these three species. This contribution conclusively distinguishes between A. macrocheles and A. amblyonyx and points out the need for a comprehensive review involving all species of the larger A. macrocheles group.

Using integrative taxonomy to establish the status of Alpheus peasei (Armstrong, 1940) (Decapoda: Alpheidae) as a single species throughout its distribution.

The distribution of the western Atlantic snapping shrimp Alpheus peasei (Armstrong, 1940) has a large gap (approx. 12° of latitude) between Tobago and the northeast of Brazil (State of Ceará). Here we analyzed specimens of A. peasei from its entire distribution range and type-locality (Bermuda), to test the hypothesis that they belong to a single species. The morphological analysis included the usual taxonomic characters as well as additional ones (such as mouthparts). The molecular analysis was based on the mitochondrial genes Cytochrome Oxidase I and 16S rRNA. The results of both analyses were congruent and indicated that A. peasei is a single species throughout its known distribution. As such, they indicated a connectivity between Northwestern and Southwestern Atlantic populations of A. peasei. The gap in distribution may be explained by scarce samplings in the North Brazil Shelf province and/or by passive larval dispersal. Our results also extend the known distribution of A. peasei in the northwestern Atlantic (Barbados, Belize and Costa Rica), and add a new record from the Brazilian coast (Pernambuco).

A multigene and morphological analysis expands the diversity of the seabod shrimp Xiphopenaeus Smith, 1869 (Decapoda: Penaeidae), with descriptions of two new species.

After being stable for nearly a century, the taxonomic history of the genus Xiphopenaeus has been marked by many changes in the last three decades. The taxonomic status of the Atlantic species has a low resolution, and many species are still undefined and grouped as cryptic species. Here we employed an integrative approach to define the species of Xiphopenaeus and the morphological characters needed to differentiate them. We combined the analyses of two molecular markers (COI and 16 S rDNA), scanning electron microscopy and light microscopy. Based on specimens from 17 localities from the Atlantic and Pacific oceans, we detected five divergent genetic groups, three in the Atlantic (A1, A2, A3) and two in the Pacific (P1, P2). Male secondary sexual characters were able to differentiate four out of the five genetic groups. Group A1 corresponds to X. kroyeri, and A2 and A3 correspond to new species. We redescribed the genus and two new species are described and illustrated: Xiphopenaeus dincao nov. sp. (A2) and Xiphopenaeus baueri nov. sp. (A3). Since the holotype of X. riveti was missing and the specimen analysed from group P2 was a female, the status of the species of Xiphopenaeus from the Pacific remains unresolved.

DNA sequence database as a tool to identify decapod crustaceans on the São Paulo coastline.

DNA barcoding has emerged as an efficient tool for taxonomy and other biodiversity fields. The vast and speciose group of decapod crustaceans is not an exception in the current scenario and comparing short DNA fragments has enabled researchers to overcome some taxonomic impediments to help broadening knowledge on the diversity of this group of crustaceans. Brazil is considered as an important area in terms of global marine biodiversity and some regions stand out in terms of decapod fauna, such as the São Paulo coastline. Thus, the aim of this study is to obtain sequences of the mitochondrial markers (COI and 16S) for decapod crustaceans distributed at the São Paulo coastline and to test the accuracy of these markers for species identification from this region by comparing our sequences to those already present in the GenBank database. We sampled along almost the 300 km of the São Paulo coastline from estuaries to offshore islands during the development of a multidisciplinary research project that took place for 5 years. All the species were processed to obtain the DNA sequences. The diversity of the decapod fauna on the São Paulo coastline comprises at least 404 species. We were able to collect 256 of those species and sequence of at least one of the target genes from 221. By testing the accuracy of these two DNA markers as a tool for identification, we were able to check our own identifications, including new records in GenBank, spot potential mistakes in GenBank, and detect potential new species.

Checklist of decapods (Crustacea) from the coast of São Paulo State (Brazil) supported by integrative molecular and morphological data: II. Infraorder Caridea: family Alpheidae.

This study is part of a series of checklists resulting from a long-term multidisciplinary project on the biodiversity of decapod crustaceans from the marine and coastal environments (including estuaries) of São Paulo State (Brazil). For that, we integrated molecular techniques (mitochondrial DNA markers) and morphological analyses of adult specimens for an accurate and detailed identification. The DNA markers were used when the morphological identification was doubtful, particularly in the recognition of cryptic species. This second manuscript presents a checklist of the Alpheidae caridean shrimps from the coast of São Paulo. We report the occurrence of Alpheus cf. paracrinitus and Synalpheus townsendi for the first time in the region. Based on our survey, 39 species of Alpheidae are known for this region: Alpheus (21 spp.), Athanas (2 spp.), Automate (2 spp.), Leptalpheus (1 spp.), Salmoneus (3 spp.), and Synalpheus (10 spp.). We collected 28 species and obtained cytochrome oxidase subunit I (barcode region) and/or 16S partial sequences of 26 of them. These sequences may be used for phylogenetic and populational analyses in further studies.

Checklist of decapods (Crustacea) from the coast of the São Paulo state (Brazil) supported by integrative molecular and morphological data: I. Infraorder Caridea: families Hippolytidae, Lysmatidae, Ogyrididae, Processidae and Thoridae.

The current checklist is the result of a long-term multidisciplinary project which combined molecular techniques (mitochondrial DNA markers) and morphological analyses of adult specimens for an accurate and detailed identification of the total biodiversity of decapod crustaceans from marine and coastal (including estuaries) environments of São Paulo State (Brazil). This is the first of a series of reports and providing a checklist of caridean shrimps of the families Hippolytidae (5 spp.), Lysmatidae (6 spp.), Ogyrididae (2 spp.), Processidae (5 spp.) and Thoridae (1 sp.). We collected material of 13 species out of 19 recorded, with sequences of cytochrome oxidase subunit I - barcode region and 16S generated from 10 species. The previous record of Lysmata cf. intermedia for São Paulo is actually L. jundalini, as the first record in São Paulo/South Atlantic waters. The molecular data were helpful to confirm the identification of some species, as the occurrence of L. wurdemanni which is confirmed in the South Atlantic Ocean based on morphological, color pattern and molecular data.

Global biogeography, cryptic species and systematic issues in the shrimp genus Hippolyte Leach, 1814 (Decapoda: Caridea: Hippolytidae) by multimarker analyses.

Hippolyte is a genus of small bodied marine shrimps, with a global distribution. Here, we studied the phylogenetic and biogeographic relationships amongst the species of this genus with two mitochondrial and two nuclear markers, using Bayesian Inference, Maximum Likelihood, genetic divergence, molecular clock and S-DIVA. In addition, the Indo-West Pacific genus Alcyonohippolyte was included. Based on sequences from 57 specimens of 27 species, we recovered a robust biogeographic scenario that shows the Indo-West Pacific as the probable ancestral area of the genus Hippolyte, which emerged in the Paleocene, followed by dispersal in three general directions: (1) South Pacific, (2) eastern Atlantic and Mediterranean Sea and (3) Americas, the latter with a primary colonization in the eastern Pacific followed by a radiation into the western Atlantic. Our analysis reveals that the species of the H. ventricosa group do not constitute a monophyletic group and Alcyonohippolyte does not constitute a reciprocally monophyletic group to Hippolyte, with both genera herein synonimised. The relationships and systematic status of several transisthmian and Atlantic species are clarified.

Morphological and molecular data reveal the cryptic diversity among populations of Aegla paulensis (Decapoda, Anomura, Aeglidae), with descriptions of four new species and comments on dispersal routes and conservation status.

The taxonomy of the Brazilian aeglid species Aegla paulensis Schmitt, 1942 from two disjunct hydrographic basins is revised using morphological and molecular data. Results show that six disjunctive populations of Aegla paulensis form a species complex. Aegla paulensis sensu stricto is redescribed and Aegla rosanae Campos Jr., 1998 is revalidated. The four remaining populations previously assigned to Aegla paulensis are now recognized as different species, namely Aegla  vanini n. sp., Aegla japi n. sp., Aegla jaragua n. sp. and Aegla jundiai n. sp. All new species are described and illustrated and are well supported by both morphological and molecular data. Aegla lancinhas Bond-Buckup & Buckup in Santos et al., 2015, which until recently was confounded with Aegla paulensis s. str., is supported as a valid species. A key to all members of the A. paulensis species complex is provided, and their phylogenetic and biogeographic relationships to other closely related species is discussed.