Tacinga

Abstract: A B S TRA CT The genera of the Opuntioideae are surveyed for certain spine and glochid structures. Retrorse scabrosity of both spines and glochids is regarded as characteristic of the subfamily. Critical differences are noted in the bases of the glochids, flattened fish-tail forms being found in Opuntia, Nopalea, Cylindropuntia, Tephrocactus, and Tacinga, and enlarged, rounded, hollow forms in Pterocactus and Grusonia. Small unflattened bases are found in Pereskiopsis and Quiabentia. Minor variations of the flattened form of glochid base are noted in Cylindropuntia, Austrocylindropuntia, and Opuntia brasiliensis; and the possible significance of the structures is discussed. THE SPINES AND GLOCHIDS of the Cactaceae have been selected for study with the scanning electron microscope because of the varied cellular structure and the resistance of the material to collapse. The initial intention was to supplement the "meager and scattered" anatomical information mentioned by Boke (1941, 1944), but emphasis on comparisons among many species has revealed some unexpected features of potential taxonomic significance and has provided the basis for further studies by conventional microscopic techniques. The present study attempts to coordinate the two disciplines of anatomy and taxonomy as applied to the subfamily Opuntioideae of the Cactaceae.

Abstract: Summary: Despite having a high diversity of cacti, the knowledge of the family in the northeastern region of Brazil still suffers from field collection gaps. This is the case for the state of Ceara — one of the lesser known areas for Cactaceae in Brazil. We made a survey of literature and herbarium holdings for the family in Ceara. Field studies have reduced the number of gaps in records for Cactaceae in the state. We gathered 252 findspot records, including nine new records of taxa for the state: Arrojadoa rhodantha, Brasiliopuntia brasiliensis, Discocactus zehntneri, Melocactus oreas, Pereskia aculeata, Pilosocereus catingicola subsp. salvadorensis, Tacinga palmadora, Tacinga ×quipa and Tacinga subcylindrica (stat. nov.; syn. T. inamoena subsp. subcylindrica). We also collected taxa that had not been previously documented by herbarium vouchers: Discocactus bahiensis, Harrisia adscendens and Pilosocereus flavipulvinatus. Ceara has 24 native taxa, one of which is endemic to the state: Pilosocereus chrysos...

Abstract: The Brazilian state of Bahia is home to 98 out of 260 species of the country's native Cactaceae. The Floresta Nacional Contendas do Sincora (FLONA Sincora), in the Municipio de Contendas do Sincora has vegetation, climate and temperatures typical of the Caatinga biome. The survey intended to increase the knowledge regarding the cacti of protected areas within the state of Bahia and was based on fieldwork carried out in April and July 2014 and February 2015, complemented by studies of herbarium material. The FLONA Sincora harbours 11 genera and 14 species within its area: Arrojadoa penicillata (Gurke) Britton & Rose; Brasilicereus phaeacanthus (Gurke) Backeb; Brasiliopuntia brasiliensis (Willd.) A. Berger; Cereus jamacaru DC.; Espostoopsis dybowskii (Rol.-Goss.) Buxb; Hylocereus setaceus (Salm-Dyck) R. Bauer; Melocactus concinnus Buining & Brederoo; Pereskia aureiflora F. Ritter; Pereskia bahiensis Gurke; Pilosocereus catingicola (Gurke) Byles & G.D. Rowley ssp catingicola; Stephanocereus leucostele (Gurke) A. Berger; Tacinga inamoena (K. Schum.) N.P. Taylor & Stuppy; Tacinga funalis Britton & Rose; and Tacinga palmadora (Britton & Rose) N.P. Taylor & Stuppy. Of these, Espostoopsis dybowskii, Pereskia bahiensis and Stephanocereus leucostele are endemic to Bahia. The east Brazilian genus Tacinga was the largest, with three species. An identification key for all taxa, together with descriptions, illustrations, taxonomic and conservation and threat statements are presented.

Abstract: Phylogenetic analyses based on molecular data revealed that the Venezuelan endemic, Opuntia lilae, considered a species of Opuntia s.s. since its description, actually represents a species of the mostly Brazilian clade, Tacinga. Through ancestral state reconstruction, we also identify morphological synapomorphies of the Tacinga clade, which further support the relationship of Tacinga and Opuntia lilae. We herein transfer Opuntia lilae to the genus Tacinga, making the combination Tacinga lilae . The existence of a species of Tacinga in northeastern Venezuela suggests that members of the Tacinga clade may have previously been more widespread than their current distribution suggests or that members of the Tacinga clade may have been dispersed long distance from the Caatinga of Brazil, where Tacinga most likely originated.