Abstract We present the first formal record of the twig-girdler Psyllotoxus griseocinctus Thomson, 1868 (Cerambycidae: Lamiinae: Onciderini) attacking the rose, Rosa sp. (Rosaceae) in Southern Brazil. We provide photographs of the damage P. griseocinctus causes to the plant, as well as morphological descriptions of the immature stages and molecular diagnostic tools to identify this species. Additionally, we provide a modelled map with the known and potential distribution of P. griseocinctus and new host records for three plant species: the common walnut tree, Juglans regia L. (Juglandaceae); the cambucá tree, Plinia edulis (Vell.) Sobral (Myrtaceae); and the cherry tree, Prunus cf. serrulata Lindl. (Rosaceae).

ABSTRACT In the state of Rio Grande do Sul, there are few records of geographical distribution and host plants to species of Tomoplagia Coquillett, as well as other genera of Tephritidae, especially those associated with plants of the family Asteraceae. Here, we report the first occurrence of Tomoplagia rudolphi (Lutz & Lima, 1918) in the state of Rio Grande do Sul, inducing stem galls in Vernonanthura tweediana (Baker) H. Rob. (Asteraceae, Vernonieae), whose plant becomes a new host record for this species. In this way, is increased to nine species of Tomoplagia recorded for Rio Grande do Sul. Biological and morphological data and photos of gall, larvae, pupae at new host and distribution map of the species in Brazil are provided.

Twenty species of Tephritidae (Diptera) are recorded in association with capitula of plants in the family Asteraceae. The Tephritidae genus Tetreuarestais registered for Rio Grande do Sul for the first time. Five species of Tephritidae are newly recorded for Rio Grande do Sul, and new hosts are recorded for the following fly species: Dioxyna chilensis (Macquart), Plaumannimyia dolores (Hering), Plaumannimyia imitatrix (Hering), Plaumannimyia miseta(Hering), Plaumannimyia pallensHering, Tomoplagia incompleta (Williston), Tomoplagia matzenbacheriPrado, Norrbom & Lewinsohn, Tomoplagia reimoseriHendel, Xanthaciura biocellata(Thomson) and Xanthaciura chrysura(Thomson).

A predação oportunista dos peixes Astyanax fasciatus e Crenicichla sp. emalhados em rede de espera pelos eglídeos Aegla grisella e Aegla singularis foi observada em rios do Sul do Brasil. Estes eventos ocorreram em dois rios na Floresta Nacional de Passo Fundo, município de Mato Castelhano, RS e no município de Tanguará, SC. Em ambos os locais os peixes apresentavam um padrão de mutilação semelhante, com olhos e nadadeiras sendo consumidos primeiramente. No entanto, a predação de todo o corpo também foi registrada, provavelmente em decorrência do elevado número de eglídeos se alimentando de um mesmo indivíduo. Esse registro visa contribuir para o entendimento da dieta natural dos eglídeos em ambientes de águas continentais.

The opportunistic predation on the fishes Astyanax fasciatus and Crenicichla sp. entangled in gill net by the aeglid crabs Aegla grisella and Aegla singularis was observed in rivers of southern Brazil. These events occurred in two rivers located at the National Forest of Passo Fundo, in Mato Castelhano municipality, Rio Grande do Sul State and Tangará municipality, Santa Catarina State. In both places the fish showed similar wound pattern, with eyes and fins being consumed first. However, predation of the whole body was also recorded, probably due to the high number of aeglid crabs feeding on the same individual. This record intended to contribute for understanding the natural diet of these crabs in freshwater environments.

Thaumastocoris peregrinus é relatado pela primeira vez para o estado de Santa Catarina atacando plantas isoladas de Eucalyptus camaldulensis, Eucalyptus tereticornis e reflorestamentos de Eucaliptus grandis localizados no interior dos municípios de Chapecó, Cordilheira Alta, Xaxim e Xanxerê. No Rio Grande do sul, esse inseto já é encontrado em 10 localidades do sul do estado, e são registradas novas áreas de ocorrência nos municípios de Ernestina, Passo Fundo, Marau, Coxilha, Getúlio Vargas, Erechim, São Valentim, Erval Grande, Nonoai, Três Palmeiras, Ronda Alta, Pontão e Quatro Irmãos.

Thaumastocoris peregrinus is recorded for the first time in the state of Santa Catarina attacking isolated plants of Eucalyptus camaldulensis, Eucalyptus tereticornis and reforestation of Eucalyptus grandis located within the municipalities of Chapecó, Cordillera Alta, Xaxim and Xanxerê. In Rio Grande do Sul this insect is already found in 10 locations, and new areas of occurrence are recorded in the municipalities of Ernestina, Passo Fundo, Marau, Coxilha, Getúlio Vargas, Erechim, São Valentim, Erval Grande, Nonoai, Três Palmeiras, Ronda Alta, Pontão and Quatro Irmãos.