Catostemma lanceolatum (Malvaceae / Bombacoideae / Adansonieae), a new species from the Brazilian Amazon Author Ferreira, Carlos D. M. 0000-0001-6583-8750 cdmferreira. quararibea @ gmail. com; https: // orcid. org / 0000 - 0001 - 6583 - 8750 cdmferreira.quararibea@gmail.com Author Alverson, William S. 0000-0001-7793-0386 quararibea @ gmail. com; https: // orcid. org / 0000 - 0001 - 7793 - 0386 quararibea@gmail.com Author Demarchi, Layon O. 0000-0001-8441-2106 Instituto Nacional de Pesquisas da Amazônia, Ecologia, Monitoramento e Uso Sustentável de Áreas Úmidas, Av. André Araújo, 2936, CEP 69067 - 375, Manaus, AM, Brazil & layon. lod @ gmail. com; https: // orcid. org / 0000 - 0001 - 8441 - 2106 layon.lod@gmail.com Author Bovini, Massimo G. 0000-0002-4082-7817 bovinimassimo @ gmail. com; https: // orcid. org / 0000 - 0002 - 4082 - 7817 bovinimassimo@gmail.com Author Baumgratz, José F. A. 0000-0003-3509-293X jbaumgra @ jbrj. gov. br; https: // orcid. org / 0000 - 0003 - 3509 - 293 X jbaumgra@jbrj.gov.br text Phytotaxa 2023 2023-08-01 606 4 295 300 http://dx.doi.org/10.11646/phytotaxa.606.4.5 journal article 10.11646/phytotaxa.606.4.5 1179-3163 8202808 Catostemma lanceolatum C.D.M. Ferreira & W.S. Alverson , sp. nov. ( Figs 1 , 2 ) Type :— BRAZIL : Amazonas : Presidente Figueiredo [ S „o Sebasti„o do Uatum„], Reserva de Desenvolvimento Sustentável do Uatum „, Rio Abacate. 2°10’01”S 58°43’28”W , 10 May 2017 , L . O . Demarchi & L . E . Barcelos 872 ( Holotype : RB RB01473742 !, isotype: INPA INPA0277978 !) Diagnosis:— Catostemmae altsonii affinis sed stipularum apicibus cuspidatis (non acuminatis), foliolis lanceolatis (non obovatis vel ellipticis usque oblonga), bracteolis filiformibus 0.3–0.8 cm longis (non triangularibus circiter 0.2 cm longas), hypanthiis circiter 0.3 × 0.6 cm (non 0.05–0.1 × 0.4–0.5 cm ), calycibus 3-lobatis cum lobis circiter 1.5 × 0.6–1.1 cm (non 2-lobatis cum lobis 1–1.2 × 0.7–0.8 cm ), petalis 2.1–2.5 × 1.2–1.7 cm (non 1.8–2.2 × 0.9–1 cm ) et 420–450 filamentis liberis circiter 1.8 cm longas (non 200–280 filamentis liberis 1–1.3 cm longis) differt. Trees ca. 16 m tall. Young branches glabrous, usually glaucous. Petioles (2.5–) 3.5–4.3 cm long, glabrous, rarely glaucous; stipules ca. 0.5 × 0.4 cm , apex cuspidate, adaxial surface glabrous, abaxial surface densely to sparsely covered with brown or hyaline, fasciculate trichomes. Seedling leaves not seen. Leaflets of adult trees 11.3–13.6 × 4.1–4.4 cm , coriaceous, lanceolate to narrowly ovate, margin entire, base rounded, apex obtuse and mucronate, both surfaces glabrous, their tertiary veins alternate percurrent. Inflorescences 3–9-fasciculate, axillary. Floral pedicels 7.1–8.4 cm long, densely covered with brown, fasciculate trichomes, 3-bracteolate; bracteoles 0.3–0.8 × 0.2–0.4 cm , filiform, apex acuminate, adaxial surface densely covered with simple, hyaline trichomes on the primary veins, abaxial surface densely covered with brown, fasciculate trichomes; hypanthium ca. 0.3 × 0.6 cm , adaxial surface glabrous, abaxial surface densely covered with brown, fasciculate trichomes; calyx tube ca. 0.2 × 0.8 cm , adaxial surface glabrous or sparsely covered with simple, hyaline trichomes, its apex 3-lobate, the lobes ca. 1.5 × 0.6–1.1 cm with acute apices, adaxial surface of the lobes densely covered by simple hyaline trichomes; abaxial surfaces of the hypanthium, calyx tube, and calyx lobes densely covered with brown, fasciculate trichomes; petals 2.1–2.5 × 1.2–1.7 cm , obovate with rounded apices, white, adaxial surface sparsely covered by simple hyaline trichomes, middle and apical portions of the abaxial surface densely covered with similar trichomes; staminal column 0.2–0.3 × 0.3–0.4 cm , glabrous, bearing 420–450 free filaments, each ca. 1.8 cm long and glabrous; ovary ca. 0.3 × 0.25 cm , pyriform, superior, perigynous, 3- locular, 2 ovules per locule, densely covered with brown, fasciculate trichomes; style ca. 1.6 cm long, glabrous; stigma trifid, glabrous. Fruit not seen. Common names :— mamorana (Portuguese). Phenology :—Flowers are produced in May. Etymology :—The epithet lanceolatum refers to the shape of leaflets, which is unique among the species already described for the genus. Distribution and habitat :— The species is known only from the region of the Abacate River, a tributary of the Rio Uatum„ ( Fig. 1 ). The species occurs on banks along blackwater rivers subject to flooding ( igapó ) ( Junk et al. 2015 ). The Uatum„ and Abacate rivers have high amplitudes and a monomodal, annual flood pulse. Catostemma lanceolatum occupies intermediate flood levels, with 4 to 6 m of annual variation ( Costa 2021 ). FIGURE 1 . Geographical distribution of Catostemma lanceolatum (black square), currently known only from the type locality in the state of Amazonas, Brazil. Conservation status :—The only known population of the species is protected by a conservation unit (RDS Uatum„). Although C. lanceolatum has only one fertile record, Costa (2021) sampled igapó forests along the Abacate River and found high densities of the species, recording 333 individuals within 3 ha. This inventory was implemented in the same area where the holotype of the new species was collected and mistakenly identified as Catostemma sclerophyllum Ducke (1937: 39) . Due to the lack of other fertile collections and ecological information, we consider C. lanceolatum as Data Deficient (DD). Assessment that will be formalized by submission to the IUCN. Discussion :—This species is known from a single collection with buds and flowers, without fruits. Catostemma lanceolatum is morphologically similar to C. altsonii , but it can be distinguished by the shape of its lanceolate leaflets (vs. obovate or elliptic to oblong), larger hypanthium (ca. 0.3 × 0.6 cm vs. 0.05–0.1 × 0.4–0.5 cm ), 3-lobed calyces (vs. 2-lobate calyces) and filaments in greater quantity and size (420–450 and ca. 1.8 cm long vs. 200–280 and 1–1.3 cm long); other morphological differences can be seen in Table 1 . Catostemma lanceolatum appears to be endemic to the Abacate River, in the state of Amazonas, Brazil , while C. altsonii is endemic to the Essequibo and Mazaruni river watersheds of Guyana . Furthermore, C. lanceolatum occurs in sandy soils at elevations of ca. 15 m . s.m., while C. altsonii occurs in lateritic soils, generally at elevations of 500 to 900 m .s.m. FIGURE 2 . Catostemma lanceolatum . a. floriferous branch; b. foliar venation pattern scheme; c. flower; d. longitudinal section of the hypanthium; e. transverse section of the ovary. Photos: C.D.M. Ferreira (a, b, d, e); L.O. Dermarchi (c), based on L.O. Demarchi & L.E. Barcelos 872. TABLE 1 . Morphological comparison between Catostemma lanceolatum and C. altsonii . C. lanceolatum C. altsonii ca. 0.5 × 0.4 cm , apex cuspidate, abaxial surface densely to sparsely ca. 0.6 × 0.4 cm , apex acuminate, both surfaces glabrous, Stipules covered with fasciculate trichomes, adaxial surface glabrous usually glaucous Leaflets 4.1–4.4 cm wide, lanceolate to narrowly ovate, apex obtuse 5.1–8.5 cm wide, obovate or elliptic to oblong, apex retuse 0.3–0.8 × 0.2–0.4 cm , filiform, apex acuminate, adaxial surface densely ca. 0.2 × 0.1 cm , triangular, apex rounded, adaxial surface Bracteoles covered with simple trichomes on the primary vein up to the apex, glabrous except at apex (with sparse fasciculate trichomes), abaxial surface densely covered by fasciculate trichomes at the apex abaxial surface has a glabrous apex Hypanthia ca. 0.3 × 0.6 cm 0.05–0.1 × 0.4–0.5 cm Calyces apex 3-lobate, lobes ca. 1.5 × 0.6–1.1 cm apex 2-lobate, lobes 1–1.2 × 0.7–0.8 cm 2.1–2.5 × 1.2–1.7 cm , adaxial surface sparsely covered with fasciculate 1.8–2.2 × 0.9–1 cm , both surfaces glabrous except at apex Petals and simple trichomes, abaxial surface densely covered with fasciculate (with fasciculate trichomes) trichomes on the middle and apical portions Free filaments 420–450, ca. 1.8 cm long 200–280, 1–1.3 cm long