Abstract in English:

Abstract Lobed tegumental glands are found only in terrestrial isopods and are thought to have evolved in response to challenges associated with life on land. By examining 30 terrestrial isopod species, we aimed to determine the factors that influence the structure and distribution of the lobed glands. We discovered that lobed glands are found not only in the lateral plates and the uropods but also in the cephalothorax, the antennae, the tergites, and the pereopods of some species. The structure of the lobed glands is influenced by the phylogenetic position of an isopod. Namely, species of Diplocheta, Microcheta, and Synocheta have only one nucleus in the secretory cell, while two nuclei occur in the secretory cells of Crinocheta. By contrast, the distribution of the lobed glands in the body is influenced by the eco-morphotype of a species. Clingers and runners have numerous large lobed glands throughout the body. Creepers possess well-developed uropod glands, while lobed glands are absent or small and few in number in their pereon. Rollers have fewer lobed glands and some species apparently lack them. We also showed that several species possess several types of lobed glands. The correlation of lobed gland distribution with the eco-morphotype speaks in favor of the proposed defensive function of lobed glands.

Abstract in English:

ABSTRACT Apocyclops spartinus is a subtropical resilient copepod from impacted Peruvian wetlands, widely used for marine fish larviculture and conserved as a strain at Instituto del Mar del Peru - IMARPE. This study was conducted to test the effects of three thermal conditions (16, 20 and 24 ºC) on the individual growth of conditioned nauplii. Sub-stage growth rates, three growth models and three growth rate-dependent models were evaluated. Considering these previous experiments, naupliar growth retardation and mortality were evaluated for cold shock stress (8 ºC lower). Results indicated a progressive increase in development time by reducing temperature from 24 to 20 ºC (1.75 times) and 20 to 16 ºC (4 times). Growth rates showed a tendency to decrease, prior to metamorphosis and independent of temperature. Gompertz was the best growth model by describing sigmoidal tendency of naupliar development. Arrhenius was the best growth rate-dependent model but slightly better supported than a simple allometric model. Naupliar growth retardation was noted in nauplii that were initially hatched at 24 ºC and then swiftly transferred to a culture at 16 ºC. This cold shock stress resulted in high mortality from day four onwards. In summary, A. spartinus nauplii exhibit potential as a live food source and it is recommended that targeted thermal treatments be employed to extend the time of optimal nauplii size and thereby enhance culture techniques of this species.

Abstract in English:

Abstract The present study reports the first zoogeographical record of the squat lobster Munidopsis lauensis Baba and de Saint Laurent, 1992 from a cold-seep site in the Krishna-Godavari Basin (Bay of Bengal), Northern Indian Ocean. Molecular analysis of the partial mitochondrial gene coding for cytochrome C oxidase subunit I (COI mtDNA), and mitochondrial 16S ribosomal RNA (16S rRNA) validated its identity. The present observation extends its geographical distribution to the Northern Indian Ocean. Additionally, molecular barcodes (COI) were generated for Munidopsis scobina Alcock, 1894, Munidopsis wardeni Anderson, 1896, and Shinkaia crosnieri Baba and Williams, 1998 collected from the Indian Exclusive Economic Zone.

Abstract in English:

Abstract An analysis of reproductive potential can elucidate significant aspects of the population biology and evolution of brachyuran crabs, providing a crucial baseline for conservation efforts concerning endangered species. Johngarthia lagostoma is an endemic species to Atlantic Oceanic islands (Rocas Atoll, Fernando de Noronha, Ascension, and Trindade), and it is classified as endangered (EN) in Brazilian territory according to IUCN criteria. Until now, the reproductive potential of this species has only been described for the Ascension Island population. Therefore, we assessed the reproductive effort and fecundity of J. lagostoma on Trindade Island. A total of 43 ovigerous females in the final stage of embryonic development were analyzed. Their egg masses were removed, weighed, and counted using a volumetric method. The carapace width ranged from 55.3 to 100.1 mm (mean ± standard deviation: 75.2 ± 13.1 mm). It exhibited a good fit and positive correlation with the egg weight and fecundity data but a poor fit and negative correlation with reproductive effort. The contrasting results of fecundity (82,938 ± 43,673 eggs) and reproductive effort (10.5 ± 1.5 %) recorded for J. lagostoma reveal a well-established population on Trindade Island compared to Ascension Island. These observations provide valuable information for proposing more effective management strategies for this endangered species across these Atlantic oceanic islands.

Abstract in English:

ABSTRACT The Bythocytheridae Sars, 1866 is one of the oldest families of cytheroidean Ostracoda, with a fossil record dating back to the Silurian. During the Cenozoic this family became one of the main constituents of the deep-sea ostracod faunas, with some taxa reaching wide geographic distribution. Bythocytherids are, therefore, important for the understanding of evolution and paleobiogeography in marine Ostracoda. The main purpose of this paper is to present a study of the tribes Bythocytherini Sars, 1926 and Jonesini Schornikov, 1981 through the analysis of 47 sediment samples collected from 12 sites in the Rio Grande Rise and adjacent areas. The 11 species herein recorded are attributed to the genera Bythocythere Sars, 1866 (four species), Bythoceratina Hornibrook, 1952 (two species), Retibythere Schornikov, 1981 (two species), Rhombobythere Schornikov, 1982b (two species), and Ruggieriella Colalongo and Pasini, 1980 (one species). The occurrence of the bythocytherid species in the study area seems strongly influenced by the bathymetry, being more abundant in the shallowest site (~1,250 m) and absent beyond 3,000 m water depth.

Abstract in English:

ABSTRACT New morphological and morphometric data on females of Colobomatus belizensis Cressey and Schotte, 1983 is provided based on specimens collected from the mandibular canals of Haemulon plumierii (Lacepède) in Sepetiba Bay, state of Rio de Janeiro, southeastern Brazil. Specimens were identified as C. belizensis by the presence of a smooth, not bifid, anterior cephalic process, two pairs of dorsolateral thoracic processes with rounded tips, and third abdominal somite with one pair of lateral process with rounded tips. The original description of the female of C. belizensis was superficial, lacking details on some structures with taxonomic value that are fully described here, such as the processes ornamented with six sensilla, caudal rami armed with 11 elements, as well as the armature of the legs and ornamentation of the buccal cone. These new data add robustness to the diagnosis and confirm the validity of C. belizensis, contributing to the taxonomy of the genus Colobomatus as a whole.

Abstract in English:

Abstract In aquatic environments, the presence of biological relationships occurring in different levels of the trophic chain is widely observed and reported in the literature, especially for invertebrates using other organisms as temporary or definitive hosts. These relationships are types of symbiosis, classified as parasitism, mutualism, or commensalism. The last frequently occurs in Platyhelminthes, including the symbiotic flatworm genus Temnocephala Blanchard, 1849, that are observed living on aquatic invertebrates and vertebrates in Central and South America. However, despite an extensive list of symbiotic relationships recorded for species in this genus, no Temnocephala species has ever been reported as an ectosymbiont of Amazon prawns. Herein we report the first occurrence of Temnocephala sp. adhered to Macrobrachium amazonicum (Heller, 1862) and Macrobrachium surinamicum Holthuis, 1948, collected in the Brazilian Amazon. The prawn species and their ectosymbionts were collected in the Guamá River (01°27’54.2”S 048°26’02.6”W), between May and September 2023, using a local trap called “matapi”. We examined 108 specimens of M. amazonicum and 24 individuals of M. surinamicum; the prevalence for Temnocephala sp. was 12.96% and 16.67%, respectively, covering between one and three symbiotic flatworms per prawn. In addition, we discuss the temnocephalan/host interaction, and provide a list of Brazilian records of Temnocephala spp. on crustacean hosts.

Abstract in English:

Abstract This study details the female reproductive system morphology and seasonality in reproduction of the freshwater crab Arcithelphusa cochleariformis, widely distributed in the wetlands of Wayanad, India. Histo-morphological analyses reveal that the H-shaped female reproductive system displays the general eubrachyuran pattern. The seminal receptacle exhibits a novel combination of both heterotreme and thoracotreme patterns with ventrally attached oviduct and the presence of a mono-layered columnar secretory epithelium lining the dorsal and ventral regions. The simple type vagina, covered by a cuticle, follows the heterotreme pattern. The seminal receptacle and vagina undergo changes parallel to the annual mating and ovarian cycle. The seminal receptacle appears small, collapsed, enclosing very few secretions before mating in the proliferation phase and swollen, containing enormous spermatophores and seminal plasma after mating in the previtellogenic phase. The seminal receptacle has a withered appearance in the primary and secondary stages of vitellogenic phase and with decreased amounts of seminal plasma and several freely dispersed spermatozoa concentrated at the ventral region during the tertiary vitellogenic stage.

Abstract in English:

Abstract The Crustacea Collection of the Museu Nacional/UFRJ is one of the most relevant and representative of the Brazilian crustacean fauna. Currently, it comprises around 31,000 registered lots, of which 5,435 lots belong to the order Isopoda. This paper provides an illustrated catalog of two topotype species and 34 type species of marine isopods deposited at the Crustacea Collection of Museu Nacional/UFRJ, distributed in 22 genera, 12 families and six suborders. This collection is represented by 27 lots of holotypes, 81 lots of paratypes (15 named as allotypes), and two topotypes, published mainly by authors such as Alceu Lemos de Castro and Idalina Brasil-Lima, former researchers of Museu Nacional in the 20th century. The two topotypes species were included in the catalog as they came from the same collection event as the holotype and have been historically kept as type material within the museum collection. In general, the type materials are in good condition, however, the holotype of Robustura parvula (Albuquerque, 1978) and all type material of Pseudione serejoae Brito, Cardoso and Boyko, 2018 have been lost and await the designation of neotypes. Furthermore, this catalog is part of a larger project, in an effort to improve the curation and digitization of the museum´s type collection data. By photographing the specimens and digitizing the collection specimens´ labels, we expect to improve internal management and offer free access to the data, so as to preserve and promote the museum´s collections, which guard important and unique information on world biodiversity.

Abstract in English:

Abstract Between November 2022 and March 2023, thirty-seven Minuca osa burrow plaster casts were poured while simultaneously collecting biometric data of the occupants in Ponuga, eastern Montijo Gulf, Panamanian Pacific. Casts revealed a highly variable structure with straight and spiral sections, reaching depths down to 122 cm (mean ± SD = 73.20 ± 28.66 cm). Burrow depth and length did not differ between sexes; however, males exhibited larger burrow diameter (25.9 ± 4.61 mm) compared to females (19.48 ± 1.65 mm; Mann-Whitney, P < 0.001). Male carapace width (23.4 ± 2.15 mm) surpassed that of females (18.42 ± 1.73 mm; Mann‐Whitney, P < 0.001). Female carapace length (r 2 = 0.793) and male chela length (r 2 = 0.769) were correlated to diameter. This study presents the first description of M. osa burrow structure, providing valuable insights into this understudied species.