RESUMEN
Freshwater crustaceans of the genus Aegla are endemic to southern South America, and present greater richness in the river basins of the state of Rio Grande do Sul, Brazil. However, recent studies have shown the enormous potential for discovering new species of Aegla in the state of Paran. In the last six year the number of species recorded has almost doubled, increasing from 9 to 16. In the present work, we expand the current knowledge about the diversity of Aegla in a set of poorly explored drainage basins in the western region of the state and describe a new species, Aegla urussanga n. sp., based on morphological and molecular evidence. A combination of morphological characters supports the new species: orbital spine absent, non-elevated epigastric prominences, robust protogastric lobes with scales, anterior dorsal margin of epimeron 2 armed and with pronounced concavity, sub-rectangular palmar crest of chelipeds, internal margin of the ventral face of the ischium of the cheliped with a proximal stout spine, a distal stout spine, and up to three tubercles with spiniform scales. The molecular data, based on partial COI sequences, also support the distinction of the new species from others that occur in adjacent river basins. The species with the smallest genetic distance from A. urussanga n. sp. is Aegla castro Schmitt, 1942 which occurs in the Iguau River basin. The new species occurs in distinct streams, probably interconnected in the past and currently isolated by the Itaipu reservoir and is the second species of Aegla described from the complex of drainage basins called Paran 3 basin.
Asunto(s)
Anomuros , Animales , Brasil , Ríos , Agua DulceRESUMEN
A new species of freshwater anomuran crab, Aegla buenoi n. sp., is described. The new taxon was collected from two streams within the Cinzas River basin, Paran state, Brazil. We used morphological and molecular data (COI mtDNA) to distinguish the new species from its congeners. Aegla buenoi n. sp. is differentiated by morphological diagnostic features of the cephalothorax, chelipeds, second abdominal epimeron, and uropods. Molecular results confirm the separation of A. buenoi n. sp. from closely related species (A. castro Schmitt, 1942, A. lata Bond-Buckup Buckup, 1994, and A. jacutinga Marl Teixeira, 2020). Hence, our study increases the known diversity of aeglids and reports the first species of Aegla from the Cinzas River basin.
Asunto(s)
Anomuros , Animales , Anomuros/genética , Brasil , ADN Mitocondrial , Agua Dulce , RíosRESUMEN
A new species of freshwater anomuran, Aegla nebeccana n. sp. (Decapoda: Aeglidae), is described from the Ivaí River sub-basin, a tributary of the Paraná River Basin, in Paraná state, southern Brazil. The species is illustrated in detail with drawings and photographs. It can be distinguished from its congeners based on both morphological and molecular evidence. Morphologically, the new species resembles Aegla meloi Bond-Buckup Santos, 2015 by the general shape of the carapace and chelipeds, but differs by having a developed protograstic lobe and by the cheliped ischium ornamentation. Aegla nebeccana n. sp. has pronounced protogastric lobes, similar to Aegla castro Schmitt, 1942 and Aegla schimitti Bond-Buckup Buckup, 1994 but differs clearly from these in relation to the morphology of the cheliped palmar crest. Based on molecular analysis, A. nebeccana is sister species of Aegla parva Bond-Buckup Buckup 1994.
Asunto(s)
Anomuros , Decápodos , Animales , Brasil , Agua Dulce , RíosRESUMEN
Species of Stratiodrilus are ectocommensals of freshwater decapod crustaceans, and the genus is also the most speciose within the family Histriobdellidae. However, a global review of the species of Stratiodrilus and their hosts has not been performed in nearly two decades. Based new field collections in Brazil and a literature search, we present a list of Stratiodrilus species and their hosts. We searched for host and occurrence records in papers of species descriptions, review papers and specialized databases. Forty-one host records were summarized worldwide. All host taxa were freshwater decapod crustaceans belonging to Aegla, Astacoides, Astacopsis, Cherax, Parastacus, Samastacus, and Trichodactylus. In addition, we report four new host records for Stratiodrilus circensis, and found Aegla lata as the northernmost host record for this polychaete species. Stratiodrilus circensis also had the largest number of different host species. The greatest species richness of Stratiodrilus is found in the Neotropical region, although members of this genus are also found in Australia and Madagascar associated with crayfishes. Aegla was the most reported host genus associated with species of Stratiodrilus. We provide an updated list to the known species of Stratiodrilus and also discuss the distribution of these histriobdellids.
Asunto(s)
Anélidos , Animales , Australia , Brasil , Decápodos , MadagascarRESUMEN
A new species of aeglid crab, Aegla okora n. sp., is described. This species was found in the Iguaçu River basin in Paraná state, southern Brazil. Aegla okora n. sp. was discriminated based on morphological and molecular data (mitochondrial COI). Morphologically, the new species differs from congeners of the same river basin by the presence of a trapezoidal areola and the ventromesial border of the ischium having three tubercles, besides other exclusive additional morphological characteristics. Molecular results demonstrated that there is no overlap between the intraspecific distances of Aegla okora n. sp. and the interspecific distance of other species of Aegla added to the analysis, confirming the separation of species and increasing the known diversity of the Iguaçu River basin.
Asunto(s)
Anomuros , Animales , Brasil , RíosRESUMEN
This study describes and illustrates the morphology of the first juvenile stage of Aegla castro Schmitt, 1942. Ovigerous females were collected from May to July 2013, in Couro River (Mauá da Serra, Paraná, Brazil). These females were kept individually under controlled feeding, aeration, water temperature and quality and checked daily for hatching of juveniles. The newly-hatched juveniles were fixed in alcohol series and kept in 70% alcohol with glycerin in a 2:1 ratio prior to study under light microscopy. The newly-hatched juvenile of A. castro is the largest among aeglid species whose juveniles have been described. Aegla castro has asynchronous hatching. Some specimens were analyzed using scanning electron microscopy, revealing details of the setal morphology, some cephalothoracic appendages and lineae aeglicae. The number of setae in newly-hatched A. castro is lower than that described for other species, but does not appear to be diagnostic. However, A. castro is the only species described that combines the presence of four plumose setae on the third maxilliped exopod and 63-65 plumose setae on the maxilla exopod.
Asunto(s)
Anomuros , Animales , Brasil , Crustáceos , Femenino , RíosRESUMEN
Deformidades e anormalidades em crustáceos têm sido associadas a fatores genéticos, problemas ocorridos durante a muda, danos causados por ectobiontes, predadores ou estresse ambiental causado por produtos químicos. Espécimes de caranguejos coletados no litoral de São Paulo apresentaram anormalidades no corpo. Estes caranguejos pertencem às seguintes espécies: Callinectes ornatus (Ordway, 1863), Arenaeus cribrarius (Lamarck, 1818) e Leurocyclus tuberculosus (H. Milne Edwards & Lucas, 1843). As coletas foram realizadas por meio de arrastos camaroneiros em julho de 2008, agosto e outubro de 2009, na região de Ubatuba, Estado de São Paulo, Brasil. As anormalidades apresentadas no corpo dos caranguejos encontravam-se no dáctilo do quelípodo (C. ornatus macho adulto), defeitos na carapaça (A. cribrarius macho adulto) e alterações abdominais (C. ornatus fêmea adulta; L. tuberculosus macho adulto e fêmea ovígera). O registro de tais ocorrências pode servir na distinção de alterações causadas naturalmente ou por impacto humano, podendo fornecer ferramentas úteis no sentido de monitorar áreas ambientais não protegidas, bem como trazer subsídios ao entendimento de alterações não usuais ocorridas durante a ontogenia de espécies importantes para a comunidade bentônica.
Deformities and abnormalities in crustaceans have been associated to genetic problem, which occurred during molt process, damage caused by ectobionts, predators or environmental stress caused by chemical wastes. Some crab specimens collected in the São Paulo littoral were found having body abnormalities. They belong to the following crab species: Callinectes ornatus (Ordway, 1863), Arenaeus cribrarius (Lamarck, 1818) and Leurocyclus tuberculosus (H. Milne Edwards; Lucas, 1843). Samplings were performed by trawling during July 2008, August and October 2009 at the Ubatuba region, São Paulo State, Brazil. Body abnormalities were verified in the cheliped dactyl (C. ornatus an adult male), carapace deformities (A. cribrarius an adult male) and abdominal alterations (C. ornatus an adult female; L. tuberculosus an adult male and an ovigerous female). The record and analysis of such occurrences can help in the distinction of natural or human impact caused alterations. In this way, the occurrence study of this kind of body alterations could provide tools in order to control unprotected environmental areas, as well as bring subsides to understand the unusual variations during the ontogeny of important species in the benthic community.
Asunto(s)
Animales , Anomalías Congénitas , Xiphosura americana , ExoesqueletoRESUMEN
In this study, we captured 60 wild New World monkeys (Cebus spp.; Alouatta caraya) at the Paraná river basin, Paraná State, Brazil, and modified agglutination test (MAT) was performed to evaluate anti-Toxoplasma gondii antibodies. Prevalence was 30.2% (13/43) in Cebus spp. (capuchin monkeys) and 17.6% (3/17) for A. caraya (black and golden howler monkeys). MAT showed antibody titers of 16 (15/16) and 64 (1/16). Herein, we have observed an odds ratio (OR)=4.67 (1.06