Butia soffiae B.F. Sant'Anna-Santos, 2023
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https://dx.doi.org/10.5091/plecevo.110654 |
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https://treatment.plazi.org/id/BF7DAEF7-B65A-5DC5-BDBF-02503C214BEE |
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by Pensoft |
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scientific name |
Butia soffiae B.F. Sant'Anna-Santos |
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sp. nov. |
Butia soffiae B.F. Sant'Anna-Santos sp. nov.
Figs 1 View Figure 1 , 2 View Figure 2 , 3 View Figure 3 , 4 View Figure 4 , 5 View Figure 5 , 6 View Figure 6 , 7 View Figure 7
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).
Type.
BRAZIL - Goiás • Alto Paraiso de Goias , Cachoeira dos Cristais; 14°06 ’05.27” S, 47°30 ’00.90” W; 1244 m; 22 Jun. 2022; fl.; Sant’Anna-Santos 378; holotype: UPCB; isotypes: DIAM, HCF, MBM GoogleMaps .
Description.
Small palm, solitary, 40-60(-80) cm tall. Stem usually acaulescent or with a short stem 5-15 × 3-5 cm. Leaves 6-11 in the crown, 78-110 cm long, arched, concolourous, green; leaf sheath plus petiole (pseudopetiole) 5-10 cm long, 0.7-1.0 cm wide, flat on the adaxial surface and abaxially rounded, margins of the apparent petiole (pseudopetiole) smooth, unarmed, with barely membranaceous red fibres; true petiole absent to 3 cm long; leaf rachis 45-79 × 0.5-0.7 cm, with 33-42 pairs of pinnae; pinnae regularly arranged in a single plane (and the two sides forming a V with each other), with asymmetric and acuminate tips, clustered ramenta on the lower vein near the rachis; basal pinnae 17-22 × 0.2-0.5 cm, middle pinnae 17-40 × 0.7-2.0 cm, apical pinnae 9.8-13.4 × 0.2-0.4 cm. Inflorescences axillary, branched to one order, prophyll 6.5-14 cm long; peduncular bract 27.5-37(-54) cm long, glaucous, superficially striated, green or purple when immature (external surface), with inflated portion 18-29 × 3.5-7.3 cm (including an apical beak 0.5-0.8 cm long), 5.5-9.0 cm perimeter and 1 mm thickness; peduncle 6.0-14.0 × 0.6-1.3 cm, glabrous; inflorescence axis (the branched portion of inflorescence) 11-28 cm long, rachis 6-21 cm long, rachillae 27-32, yellowish-green to rarely purple, glabrous or with white indument, 5-17 cm long. Staminate flowers 5.3-9.8 × 2.2-4.3 mm, triangular, light purple, arranged in triads on the lower portion of the rachillae (a central pistillate and two lateral staminate flowers); the upper portion of the rachillae only with staminate flowers, staminate flowers sessile or briefly pedicellate (on the lower portion of the rachillae); sepals 3, 2.1-4.6 × 0.5-1.1 mm, acute apex, glabrous, narrow, triangular, purplish yellow or purple, connate at the base, valvate, with raphides on margins; petals 3, 4.9-8.8 × 2.0-3.0 mm, ovate, valvate, raphides on margins, no visible veins; stamens 6, 4.4-7.2 mm long, anthers 3.0-4.6 mm long, filaments 2.5-4.0 mm long, pistillode 1.3-1.4 mm long (shorter than the filaments), trifid. Pistillate flowers 9.9-13.3 × 6.2-7.8 mm, sessile, ovoid, glabrous; sepals 3, 6.3-11.5 × 5.2-7.5 mm, purple, glabrous, with raphides on the margins, no visible veins, broadly imbricate; petals 3, 6.3-10.8 × 4.5-6.4 mm, glabrous, imbricate; pistil 6.0-9.6 × 4.0-5.3 mm, glabrous, stigmas 3, 1.5-3.0 mm long, glabrous, staminodial ring slightly lobed. Fruits greenish-purple, ovoid, 20-27 × 15-17 mm, with a short beak and apical stigmatic remains; epicarp smooth, the basal third covered by a persistent perianth; mesocarp fibrous; endocarp 13-17 × 10-13 mm, bony, brown, with 3 subequatorial pores below the equator end (pores subequatorial), endosperm whitish and homogeneous embryo opposite the endocarp pores, one seed. Germination and eophyll were not observed.
Distribution.
The type population of Butia soffiae was found in the Chapada dos Veadeiros region, in the municipality of Alto Paraíso de Goiás (Fig. 4 View Figure 4 ).
Habitat and ecology.
Chapada dos Veadeiros is among the regions with the highest altitudes in the Cerrado domain, with average altitudes ranging from 800 to 1600 m ( Ribeiro and Walter 1998; Felfili et al. 2007). The predominant form of relief is a strong undulating plateau, mountainous and steep with shallow and stony soils ( Ribeiro and Walter 1998). The region is characterised by dry winters and rainy summers, with mean annual temperatures between 24-26°C and mean annual rainfall ranging from 1500 to 1750 mm ( Felfili et al. 2007). The new species was found in a cerrado rupestre area. Despite being poor in nutrients, these areas present a tree cover ranging from 5% to 20%, an average height of 2 to 4 m, and a highlighted shrub-tree stratum because they have less stony and deeper soil compared to grassland campos rupestres ( Pereira and Fernandes 2022). In addition to the great diversity of eudicotyledonous families ( Mendonça et al. 2007; SpeciesLink Network 2023), the vegetation of Chapada dos Veadeiros is characterised by a high density and important structural component of monocotyledons in the tree-shrub community, as shown by Lenza et al. (2011), mainly comprising Velloziaceae and Arecaceae (Fig. 5A-B View Figure 5 ). These families possess endemics for Chapada dos Veadeiros ( Noblick and Lorenzi 2010; Noblick 2017; CNCFlora 2023). For palms, for example, the endemic and rare Syagrus caerulescens Noblick & Lorenzi (Fig. 5B View Figure 5 ) grows in the municipality of Alto Paraíso de Goiás (see Noblick and Lorenzi 2010; Noblick 2017), near the area where B. soffiae was discovered. During the flowering time, the light-purple flowers of B. soffiae stand out from the understory green and emit a pleasant and sweet scent, acting at a distance to attract bees, observed visiting staminate flowers during anthesis (Fig. 5C-D View Figure 5 ). Bees have already been reported as one of the main pollinators of other Butia species (see Silberbauer-Gottsberger 1973; Silberbauer-Gottsberger et al. 2013). The staminate flowers of B. soffiae release large amounts of pollen (Fig. 5E View Figure 5 ) and small viscous and sweet droplets (Fig. 5F View Figure 5 ), suggesting nectar production. Flowers of other Butia species produce nectar, and staminate flowers also produce large amounts of pollen, which still function as a floral reward ( Silberbauer-Gottsberger 1973; Mercadante-Simões et al. 2006; Silberbauer-Gottsberger et al. 2013). Bees collecting pollen and feeding on nectar in staminate flowers were reported for other Butia species ( Silberbauer-Gottsberger 1973; Silberbauer-Gottsberger et al. 2013). Beetles were also frequent visitors of B. soffiae flowers (Fig. 5G View Figure 5 ). The staminodial ring of pistillate flowers has inconspicuous staminodes, composed of cells of dense cytoplasm and compact arrangement (Fig. 5H View Figure 5 ), they are markedly vascularised by xylem ends (Fig. 5H-J View Figure 5 ) and release oil-like droplets (Fig. 5K-L View Figure 5 ). The epidermis near the staminodes tested positive for lipophilic compounds (Fig. 5L View Figure 5 ), corroborating the presence of osmophores in these functional staminodes. Moreover, the floral scent was considered especially relevant for cantharophily and melittophily in some palms ( Knudsen et al. 2001). In the field, small, sweet droplets were observed on the surface of the anther (Fig. 5F View Figure 5 ), but it was impossible to ascertain whether the stamens secret these droplets or whether they oozed from another flower region. Furthermore, aphids and ants were commonly observed during the development of the fruits (Fig. 5M View Figure 5 ). The constant presence of these insects (bees, beetles, ants, and aphids) could be the reason for the marked presence of raphides in the flowers and fruits of B. soffiae . Ecologically, raphides are seen as a common defence strategy against herbivores and are often present in many organs of palms, such as flowers ( Dransfield et al. 2008).
Phenology.
The new species was collected with flowers and fruits in June of 2021 and 2022.
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.
Preliminary IUCN conservation assessment.
The single population of the new species was recorded just outside Chapada dos Veadeiros National Park. The park and the surrounding region are very susceptible to wildfires due to the dry season conditions, such as low rainfall, low relative humidity, and wind associated with the combination of human activities and climate change ( Balch et al. 2018; Fidelis et al. 2018). For instance, in 2017, a megafire event burned 78% of Chapada dos Veadeiros National Park ( Fidelis et al. 2018). In addition to the enormous extent of burning, megafires are more difficult to extinguish than common wildfires, which happen annually in the region ( Fiedler et al. 2006; Ferreira-Leite et al. 2017). Near the boundaries of Chapada dos Veadeiros National Park, where B. soffiae occurs, cattle raising is also common (Fig. 5O View Figure 5 ). In addition to cattle feeding on plant parts (Fig. 5N View Figure 5 ), ranchers burn the vegetation to promote grass regrowth for the cattle (Fig. 5O View Figure 5 ), increasing the risk of accidental fires ( Ramos-Neto and Pivello 2000; Fidelis et al. 2018). Eucalyptus sp. plantations (Fig. 5O View Figure 5 ), and charcoal production are also economic activities in the region ( Felfili et al. 2007), severely threatening the native vegetation of the area. Other regional threats, such as soil degradation and the spread of exotic grasses, also hinder conserving the Cerrado domain ( Klink and Machado 2005). Taking into account the area of occupancy (AOO = 20 km2) and the extent of occurrence (EOO = 2.854 km2), and according to the IUCN (2022) categories and criteria, B. soffiae should be considered Critically Endangered: CR B1ab(i,iii).
Additional material examined.
BRAZIL - Goiás • Alto Paraíso de Goiás, Portal da Chapada, trilha suspensa; 14°07 ’57.00” S, 47°30 ’36.00” W; 11 Sep. 2011; fl., fr.; Faria et al. 1715; UB • Alto Paraiso de Goias , Rodovia entre Teresina de Goias e Alto Paraíso; 14°07 ’57.00” S, 47°30 ’35.99” W; 25 Sep. 2011; fl.; Pastore 3371; HUEFS GoogleMaps .
Pinnae anatomy.
The pinnae are amphistomatic and covered by two types of epicuticular waxes: horizontal plates and hook-shaped filaments (Fig. 6A-B View Figure 6 ). The hook-shaped filaments cover the small depressions above the stomata (Fig. 6A-B View Figure 6 ). The subsidiary cells are arciform in the leaf transverse section, and are positioned entirely below the cuticle level (Fig. 6A-C View Figure 6 ). The hypodermis forms one to two layers of cells longitudinally elongated to quadrangular shaped on both surfaces (Fig. 6D-F, H View Figure 6 ). The hypodermis forms two layers above the vascular bundles, but below the stomata, it is interrupted by substomatal chambers (Fig. 6D-F, H View Figure 6 ). The lamina is isobilateral, with two bands of palisade parenchyma near the hypodermis on both surfaces and a central chlorenchyma between them, composed of cells of bulky elongate-spherical shape (Fig. 6D, H View Figure 6 ). Both adaxial and abaxial tertiary vascular bundles are connected to the hypodermis, have no distinguishable phloem and are always partially surrounded by a sclerenchymatous sheath (Fig. 6D-F, N View Figure 6 ). Secondary and primary vascular bundles are also connected to the hypodermis on both surfaces, and the phloem is always noticeable (Fig. 6D-F, N View Figure 6 ). The secondary vascular bundles are partially surrounded by a sclerenchymatous sheath, while the primary vascular bundles are always fully surrounded by fibres (Fig. 6D, G View Figure 6 ). The primary vascular bundles always have a larger diameter, four phloem poles and noticeable protoxylem and metaxylem elements (Fig. 6G View Figure 6 ). The raphide-containing idioblasts are found in the central chlorenchyma region (Fig. 6I View Figure 6 ). The midrib is transversally truncated (Fig. 6J View Figure 6 ) and adaxially projected (Fig. 6J-L View Figure 6 ). The main vascular system of the midrib consists of two collateral bundles, surrounded by a fibrous ring and 14-20 accessory bundles, 2 of them with reinforced sheath (Fig. 6J-M View Figure 6 ). The smaller accessory bundles are sharper under polarised light (Fig. 6L View Figure 6 ). The expansion tissue is interrupted and four-layered (Fig. 6J, M View Figure 6 ). Non-vascular fibre bundles were absent from the midrib of B. soffiae . In cross-section, the margin is quadrangular and possesses 2 tertiary vascular bundles; the abaxial one is larger and occupies more than half of the margin (Fig. 6N View Figure 6 ). Table 2 View Table 2 compares the pinna anatomy of B. soffiae , B. buenopolensis , B. archeri , and B. purpurascens .
No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.
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