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| Butia soffiae B.F.Sant’Anna-Santos, |
Abstract
Background and aims – The highlands of the Chapada dos Veadeiros region comprise one of the largest savannah areas in central Brazil. The region includes large areas of the rare and little-known cerrado rupestre, which is home to numerous endemic species. During research on the Arecaceae flora of Chapada dos Veadeiros, a new species of Butia was discovered, and it is described here.
Material and methods – The morphology and anatomy are described based on field collections. Following the default methodology, pinnae and flowers were analysed using LM (freehand cross- and longitudinal sections) and SEM. The new species is compared to its morphologically similar species from the Brazilian central plateau, and an identification key and distribution map were established.
Key results – At first sight, the new species Butia soffiae resembles B. archeri, but with staminate and pistillate flowers, which are always purple, different in size, and congested in the rachillae. After close inspection, it is morphologically allied to B. buenopolensis, differing mainly by its glaucous peduncular bract – similar size to the inflorescence, herbaceous peduncle, numerous rachillae, purple floral colour, and inconspicuous staminodes. Differences in leaf anatomy, such as the presence of raphides, a cross-sectionally truncated midrib, and the number of accessory bundles on the midrib, also support the description of a new species. Two structures were recorded for the first time for the genus: squamiform trichomes at the base of the pistil and osmophores on the staminodes. The new species is assessed as Critically Endangered based on the restricted area of occurrence and anthropogenic threats.
Conclusion – Butia soffiae is the first endemic Butia species described in Chapada dos Veadeiros. The type population is located near Chapada dos Veadeiros National Park, which is the subject of a bill that aims to reduce its area by 73%. The discovery of this new species reinforces the uniqueness of the local flora and the importance of maintaining the park.
Keywords: acaulescent, Goiás State, new species, Palmae, plant anatomy, raphides, squamiform trichomes, taxonomy
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| Butia soffiae. A. Arched leaves. B. Close-up of an asymmetrical pinna tip. C. Branched inflorescence and congested flowers. D. Rachillae. E. Sepals, connate at the base. F. Petal: ventral view. G. Stamen: lateral view. H. Stamen: dorsal view. I. Close-up of a pistillode. J. Pistillate flower: imbricate sepals. K. Petals, imbricate at the base and valvate at the tip. L. Valvate tip. M. Pistil. N. Fruit: persistent perianth. O. Endocarp pore. A–M from Sant’Anna-Santos 378 (UPCB, holotype), fruit of N and endocarp of O added from habitat photographs. Illustration by Gustavo Surlo. |
Butia soffiae B.F.Sant’Anna-Santos, sp. nov.
Diagnosis: Butia soffiae is similar to B. buenopolensis B.F.Sant’Anna-Santos, from which it differs by congested pinnae on the leaf rachis (vs lax pinnae); longer rachis (45–79 cm vs 25–40 cm); fibres of the pseudopetiole red (vs brown); true petiole frequently absent (vs always present); longer prophyll (6.5–14 cm vs 5–6.5 cm); glaucous peduncular bract (vs glossy); peduncular bract almost the same size as the inflorescence (vs smaller than the inflorescence); herbaceous peduncle (vs woody); longer inflorescence axis (11–28 cm vs 4.0–7.5 cm); flowers light purple (vs dark purple); inconspicuous staminodes (vs conspicuous staminodes); more rachillae (27–32 vs 4–7).
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| Floral morphology of Butia soffiae. A. Rachillae bearing only staminate flowers on its upper 2/3 and triads on its lower 1/3: staminate flowers in anthesis (white arrowheads). B. Triad: a central pistillate flower flanked by two staminate flowers. C. Briefly pedicellate staminate flower (dotted white circle) and floral bracteole (white arrowhead). Sepals (grey dot). Petals (white dot). ... |
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| Vegetative and reproductive morphological aspects of Butia soffiae. A. Solitary habit of specimens (white rectangles) in the understory. B. The black arrowheads indicate the congested pinnae. Leaf rachis (white arrowhead). C. Asymmetric and acuminate tip of a pinna (pi). D. Ramenta (ra). E. Prophyll (pr). F. Closed peduncular bract (pd) glaucous and purple. G. Closed peduncular bract (pd) glaucous and green. H. Yellowish-green rachillae (ra). I. Early stage of fruit development: sepals (se), petals (pe), and shiny aspect of perianth margins (white arrowheads). J. Purple fruit: apical stigmatic remains (white circle) and persistent perianth (pe). K. Endocarp in lateral view: subequatorial pore (po). Photographs by Bruno F. Sant’Anna-Santos. |
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| Habitat and morphoanatomical aspects of Butia soffiae with ecological implications and threats in the vicinity of the type population. A. Specimen of Velloziaceae (white arrowhead). B. Inflorescence of the endemic and rare Syagrus caerulescens. C. Bee visiting a stamen. D. Bee visiting a petal. E. Pollen (po). F. Droplet of nectar (white arrowhead). G. Beetle visiting a petal. H. Frontal view of staminodial ring: staminode (black circle), raphides (white arrowheads), and vascularisation (black arrowheads), LM. I. Detail of H: vascularisation (black arrowhead) under polarised light, LM. J. Cross-section of the staminode’s vascularisation (black dotted), LM. Ovary (ov). Staminode (st). K. Frontal view of staminode showing the oil-like droplets (white arrowhead). L. Sudan staining of lipophilic compounds (white arrowhead). M. Infructescence: aphids (white circles) and ants (white arrowheads). N. Inflorescence at pre-anthesis grazed by cattle. O. Landscape view of a pasture nearby the type population showing a rocky outcrop (black arrowhead), a Eucalyptus sp. plantation (grey arrowhead), cattle, and non-native grasses (white arrowheads). Butia soffiae (white rectangle) in the foreground. Photographs by Bruno F. Sant’Anna-Santos. |
Etymology: The epithet honours Dr Patrícia Soffiatti, affectionately called Soffi by her friends and mentees. She is a Brazilian scientist and professor at the Department of Botany at the Federal University of Paraná (UFPR), mainly devoted to studying Cactaceae. Her deep knowledge of the environment where cactuses and palms cohabit and her expertise in plant anatomy were essential to the description of the newly acaulescent Butia and Syagrus species discovered by our team on the Serra do Cabral massif.
Bruno Francisco Sant`Anna-Santos. 2023. A New Purple-flowered Butia (Arecaceae) from the Highlands of the Chapada dos Veadeiros (Brazil). Plant Ecology and Evolution 156(3): 383-398. DOI: 10.5091/plecevo.110654
