The study investigated the diversity patterns and community structure of free-living marine nematodes at five beaches, Shankarpur, Mohona, Old Digha, New Digha and Oceana, along the Digha–Shankarpur coastline, West Bengal. Maturity index (MI), coloniser–persister class percentage (c–p%), Shannon diversity index (H′), the index of trophic diversity (ITD) and the presence of sensitive/tolerant genera were applied to determine the community structure. A total of 42 nematode genera were recorded. Pronounced spatial differentiation occurred along localised environmental gradients. Mohona beach, adjacent to a fishing harbour, exhibited the highest disturbance, marked by the lowest diversity, the lowest maturity index, the highest index of trophic diversity and the dominance of opportunistic Daptonema sp. Spearman rank correlation and canonical correspondence analysis confirmed that environmental parameters significantly structured generic distribution, notably highlighting strong relationships with dissolved oxygen. These findings reinforce the efficacy of marine nematodes as sensitive bioindicators for coastal biomonitoring.
Polycentropodidae is one of the most diverse families within the suborder Annulipalpia, encompassing 940 species across 18 extant genera. Polycentropus Curtis, 1835 is the second-largest genus in the family, with about 200 species worldwide, and its greatest richness is concentrated in the Neotropical region. In Brazil, 28 species have been recorded, 26 of which occur in the Atlantic Forest domain. In this study, we describe and illustrate two new species of Polycentropus from the Atlantic Forest in south-eastern Brazil: Polycentropus bitucai, from Parque Nacional do Caparaó on the border between the states of Espírito Santo and Minas Gerais, and Polycentropus magdalenae, from the vicinity of Parque Nacional da Serra da Bocaina, situated on the boundary between the states of São Paulo and Rio de Janeiro. This work contributes to narrowing the biodiversity gaps regarding caddisflies in the Atlantic Forest, addressing the Linnean shortfall in one of the world's most threatened biodiversity hotspots.
To address the Haeckelian deficit in Apobaetis, a genus in which the adult stage remains unknown for most species, with imagos currently described for only six of the 22 valid species, we provide new descriptions of the adult stages of A. jacobusi (male and female), A. pasternakae, A. nisiae and A. biancae (females). To improve species delimitation, we also illustrate the gonovectes and penial bridges of A. jacobusi, A. irai and A. fiuzai. These data substantially expand the morphological knowledge of the genus and provide new insights into the diversity of male genital structures, particularly variation in the penial bridge and gonovectes, morphological features that have not previously been investigated in Apobaetis.
Gripopterygidae comprises about 60 species in Brazil, most of which inhabit mountainous streams along the Atlantic coast. The genus Tupiperla includes 26 species, mainly occurring in mountainous streams of the Atlantic Forest. We present a checklist of Gripopterygidae from the Araras Biological Reserve (REBIO Araras), Rio de Janeiro State, Brazil. We documented 15 species representing four genera. Three species are reported from Rio de Janeiro for the first time: Paragripopteryx blanda, P. delicata and P. intervalensis. Additionally, a new species, Tupiperla nessimiani, is described and illustrated based on male specimens collected in REBIO Araras. Tupiperla nessimiani is distinguished by the narrow extension of tergum 10 with divergent margins and a shallow apical incision, and by the elongate, rod-like paraprocts, bearing a dark, thorn-like subapical spine. This study contributes to reducing Linnean and Wallacean shortfalls in Brazilian Gripopterygidae.
In this study, we describe a new species, Scirtes jefersoni (Coleoptera, Scirtidae), based on male, female, pupa and larva specimens, collected from fallen palm bracts (‘capembas’) and palm leaves in temporary forest puddles and streams across four localities in the state of Amazonas, northern Brazil. Larvae were reared under laboratory conditions until adult emergence, allowing the association between immature and adult. Late larval instars and pupae were described, representing the first description of a Scirtes larva and pupa from South America. Scirtes jefersoni is the first species of Scirtes described from Brazil in 75 years; the last one was described in 1951.
