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All 32 Brazilian species of Parodia Speg (Cactaceae) occurring in Rio Grande do Sul State are considered threatened, according to the IUCN criteria. Until 2021, Parodia rechensis (CR) was known by only two small populations. However, a new population with over 400 individuals was discovered in 2021, prompting the study of its reproductive biology as a way to promote its conservation. Anthesis, breeding system, and natural pollination were studied in the field. The breeding system was studied by applying controlled pollination treatments to plants excluded from pollinators (bagged). Germination features were studied at the Seed Bank of the Porto Alegre Botanical Garden under controlled temperatures (20, 25, and 30 °C). The anthesis is diurnal and lasts for up to four days. The flowers offer pollen as the sole resource to the pollinators. The study species is unable to set fruit and seed without the agency of pollinators and has self-incompatible (unable to set fruit and seeds when pollinated with pollen of the same individual) characteristics that can considerably restrict its reproduction. Native bees of Halictidae and Apidae (Hymenoptera) are the main pollinators, with a smaller contribution of Melyridae (Coleoptera) and Syrphidae (Diptera). Natural fruit set is moderate (≤64%, per individual), but the species presents vegetative growth, producing several branches from the mother plant. Seeds showed the optimum germination rate at 20 °C and an inhibition of 75% in germinability at 30 °C. Our findings suggest the need to manage the species' habitat to guarantee the permanency of the plants and healthy populations of pollinators as well. Our findings raise concerns about the germination and establishment of new individuals in the context of rising temperatures caused by climate change. Suggestions for the possible management of the extant populations are made. [ABSTRACT FROM AUTHOR]

Taxonomic researchers have used multiple sources of evidence to support species hypotheses and delimitations. Grammostola Simon (Mygalomorphae: Theraphosidae) comprises 20 valid species endemic to South America, six occurring in Brazil. The classical morphological approach based mainly on genitalia may be misleading in recognizing species in this genus. Thus, we used morphology, geographical distribution, genetic distance, and phylogeny to support the redescription of Grammostola pulchra from southern Brazil, a species described a century ago. We also diagnosed and illustrated the species. Males have a developed apical keel at the apex of the embolus; for the first time, this type of structure has been reported in a species of Grammostola . The molecular analyses using the partial sequence of Cytochrome c oxidase subunit I showed 7% of genetic distance ( p -distance) between G. pulchra and Grammostola anthracina . Distance and tree-based methods (ASAP and bPTP, respectively) assigned G. pulchra as a valid species. The gene-tree under Bayesian and Maximum-Likelihood recovered a similar topology, placing G. pulchra as closely related to Grammostola burzaquensis and G. anthracina . Morphological characters which could be important in the taxonomy of the genus are further discussed.