Tabaroa caatingicola L.P.Queiroz, G.P.Lewis & M.F.Wojc.

First published in Kew Bull. 65: 193 (2010)
This species is accepted
The native range of this species is Brazil (Bahia). It is a tree and grows primarily in the seasonally dry tropical biome.

Descriptions

de Queiroz, L.P., Lewis, G.P. & Wojciechowski, M.F. 2010. Tabaroa, a new genus of Leguminosae tribe Brongniartieae from Brazil. Kew Bulletin 65: 189. DOI: https://doi.org/10.1007/s12225-010-9202-7

Distribution
Brazil: Bahia, known only from a very narrowly restricted area in Southwestern Bahia, on the lower slopes of the Rio de Contas mountain range.
Ecology
Seasonally dry tropical forest (Caatinga).
Conservation
Tabaroa caatingicola is Critically Endangered (CR; IUCN 2001), since it occurs only in a small area estimated at c. 12 km2. Although the plant is locally common, this area is under threat as a result of fruit plantation and cattle-raising.
Phenology
The species has only once been collected in flower, in October. The fruiting period is known to extend from November to May. Etymology. The name Tabaroa is derived from the Tupi word ‘taba’ (Portuguese ‘tabaréu’, female ‘tabaroa’), meaning the inhabitants of the Taba, (an Amerindian village). The term is still used for the shy people of remote localities and we use it to highlight the recent discovery of this previously overlooked new genus in NE Brazil. The specific epithet ‘caatingicola’ indicates its occurrence in Caatinga vegetation.
Vernacular
Pau-jacaré (crocodile wood) because of the resemblance of the bark to crocodile skin.
Note
Tabaroa caatingicola is only known to occur in a small area of southwestern Bahia. The vegetation of the area is an arboreal form of Caatinga, growing on sandy soil, a form of Seasonally Dry Tropical Forest,characteristic of Northeastern Brazil. T. caatingicola is one of the most common trees in this narrowly restricted locality, and grows together with Aspidosperma pyrifolium Mart. (Apocynaceae), Zanthoxylum hamadryadicum Pirani (Rutaceae), Thiloa glaucocarpa Eichler (Combretaceae), Commiphora leptophloeos (Mart.) J. B. Gillett (Burseraceae), and the legumes Chloroleucon foliolosum (Benth.) G. P. Lewis, Poeppigia procera C. Presl and Lonchocarpus araripensis Benth. The area also harbours some rare plants that just extend into neighbouring areas, e.g. Aeschynomene soniae G. P. Lewis (Leguminosae), Gorceixia decurrens Baker (Compositae), and Holoregmia viscida Nees (Martyniaceae), the latter two being monospecific genera.
Type
Brazil, Bahia, A. M. Giulietti et al. 2587 (holotypus HUEFS; isotypi HUEFS, K, RB).
Morphology General Habit
Tree 5 – 8 m, canopy widely elliptic c. 3 – 5 m diam., foliage deciduous in dry season; trunk 12 – 20 cm DBH, bark light grey with darker wavy stripes that interlink and cross over to form a pattern suggestive of crocodile skin, inner bark dark green; indumentum velutinous comprising erect, brown, c. 0.5 mm long hairs, dense on young branches, very young leaves and inflorescence axes during budding stage, becoming sparser on branches, petiole and leaf rachis during flowering phase, and finally glabrate on branches, petiole, leaf rachis and infructescence axis when fruiting
Morphology Leaves Stipules
Stipules linear, c. 3 × 0.5 mm, caducous
Morphology Leaves
Leaves alternate, imparipinnate; petiole 2.2 – 2.8 cm, flat along the upper side, pulvinus very swollen, conical, c. 3 × 2 mm, rachis 5.9 – 8.4 cm, when young with red colleters intermixed with the indumentum near the base of the petiolules, interfoliolar segments 2 – 2.4 cm; stipels absent; leaflets (5 –) 7 – 9, opposite, the basal ones sometimes subopposite, pinnately veined, main vein prominent on lower surface, lateral veins 10 – 12 pairs, mostly parallel, becoming curved and brochidodromous near the margin, upper surface sparsely appressed pilose to glabrous, lower surface soft pilose becoming sparsely pubescent during fruiting phase, basal leaflets 3.9 – 4.2 × 2 – 2.2 cm, ovate, base truncate to cordate, apex obtuse, lateral leaflets 4.6 – 4.8 × 2.1 – 2.2 cm, elliptic to oblong, base truncate, rounded or cordate, apex obtuse to rounded, distal leaflet 4.5 – 4.7 × 2.4 – 3 cm, elliptic to suborbicular, base rounded, apex rounded to truncate, all leaflets 1.5 – 2 × longer than wide; petiolules 2 – 2.5 mm long
Morphology Reproductive morphology Inflorescences
Inflorescence a terminal, almost pendent, pyramidal panicle, c. 6.5 cm long, 6.5 cm wide at the base, comprising 10 – 16 racemose inflorescence branches; branches 2.3 – 3.8 cm long, flowers crowded and spirally arranged, basal branches sometimes presenting second order branches; bracts c. 1.5 × 0.8 mm, linear-lanceolate, densely brown pubescent, caducous; bracteoles 1.2 – 1.4 × c. 0.3 mm, linear, densely brown pubescent, caducous
Morphology Reproductive morphology Flowers
Flowers 4.5 – 5 mm long, lemon-scented, zygomorphic, papilionoid, hypanthium short, campanulate, c. 0.5 × 1 mm; calyx c. 4 × 3.5 mm, campanulate, outer surface densely velutinous with long, erect, c. 0.5 mm long, brown hairs, inner surface densely sericeous with appressed, short, c. 0.2 mm long hairs, the two upper lobes fused almost to their apex forming a straight, oblong lobe 2.8 – 3 × 2.5 – 2.8 mm, apex emarginate, lateral lobes 2.3 – 2.5 × 2.3 mm, patent, triangular, apex acute, lower lobe 2.8 – 3 × 1.8 mm, patent, oblong-triangular, apex acute; petals exserted from the calyx, standard petal fleshy, claw and central portion of the lamina lemon-green, margin of the lamina deep wine-red, the margins slightly inrolled at c. 45°, claw 1.5 – 1.7 × 1.3 mm, lamina 3 – 3.2 × 4.2 – 4.5 mm, widely ovate, emarginate; wing petals with claw and base of the lamina green, most of the lamina lilac but with a triangular dark wine-red blotch expanding from the middle to the apex, claw 0.8 – 1 mm, lamina 3.5 – 3.8 × 1.5 mm, oblong, slightly oblique, apex rounded, upper side with base cordate and laterally expanded into a pocket; keel petals with claw and proximal half of the lamina green, distal half of the lamina dark wine-red, claw 1 – 1.2 mm, lamina 2.8 – 3 × 1.5 mm, oblong, upper margin almost straight, very slightly convex, base cordate and laterally expanded into a pocket, lower margin curved; stamens 10, united into a 1.8 – 2 mm sheath open along the upper side, filaments free for 1.5 – 1.8 mm, anthers c. 0.6 × 0.3 mm, oblong; pollen grains isopolar, tricolpate, endaperture indistinct, colpus operculate; ovary sessile, 1.9 – 2 × 0.8 mm, fusiform, covered by long, soft, woolly, white hairs, 2-ovulate; style c. 2.5 mm long, sparsely pubescent on the lower c. \( \frac{2}{3} \) part; stigma slightly widened, truncate, shortly papillose
Morphology Reproductive morphology Fruits
Fruit indehiscent, 17 – 20 × 11 – 12 mm, 1.5 – 1.6 × longer than wide, broadly-elliptic or slightly obovate, plano-compressed, apex rounded, shortly apiculate, base obtuse to rounded, margins convex, not sinuous; valves leathery, flat, reticulate with 6 – 8 transverse, raised, sinuous veins, velutinous, covered by erect, soft, brown hairs, c. 0.5 mm long, 1-seeded
Morphology Reproductive morphology Seeds
Seeds almost circular, 9 – 10 mm diam., strongly compressed, testa smooth, light brown, hilum oblong, c. 1 mm long
[KBu]

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation
Predicted extinction risk: threatened. Confidence: confident
[AERP]

Sources

  • Angiosperm Extinction Risk Predictions v1

    • Angiosperm Threat Predictions
    • http://creativecommons.org/licenses/by/4.0
  • Herbarium Catalogue Specimens

    • Digital Image © Board of Trustees, RBG Kew http://creativecommons.org/licenses/by/3.0/
  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0
  • Kew Bulletin

    • Kew Bulletin
    • http://creativecommons.org/licenses/by-nc-sa/3.0
  • Kew Names and Taxonomic Backbone

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0