Desmopsis terriflora, an extraordinary new species of Annonaceae with flagelliflory Author Martinez-Velarde, Maria Fernanda https://orcid.org/0000-0001-9022-9658 Posgrado en Ciencias biologicas, Universidad Nacional Autonoma de Mexico (UNAM), Ciudad de Mexico, Mexico Author Rodrigues-Vaz, Carlos https://orcid.org/0000-0002-4263-3573 Departamento de Botanica, Instituto de Biologia, Universidad Nacional Autonoma de Mexico (UNAM), Ciudad de Mexico, Mexico & Institut de Systematique, Evolution, Biodiversite (ISYEB), Museum National d'Histoire Naturelle-CNRS-SU-EPHE-UA, Paris, France Author Soule, Vincent https://orcid.org/0009-0001-3910-2317 Institut de Systematique, Evolution, Biodiversite (ISYEB), Museum National d'Histoire Naturelle-CNRS-SU-EPHE-UA, Paris, France Author Nge, Francis J. https://orcid.org/0000-0002-0361-8709 Institut de Systematique, Evolution, Biodiversite (ISYEB), Museum National d'Histoire Naturelle-CNRS-SU-EPHE-UA, Paris, France Author Schatz, George E. DIADE, Universite de Montpellier, CIRAD, IRD, Montpellier, France Author Couvreur, Thomas L. P. https://orcid.org/0000-0002-8509-6587 Institut de Systematique, Evolution, Biodiversite (ISYEB), Museum National d'Histoire Naturelle-CNRS-SU-EPHE-UA, Paris, France Author Ortiz-Rodriguez, Andres Ernesto https://orcid.org/0000-0003-4583-6701 Posgrado en Ciencias biologicas, Universidad Nacional Autonoma de Mexico (UNAM), Ciudad de Mexico, Mexico ortizrodriguez.ae@gmail.com text PhytoKeys 2023 2023-06-23 227 181 198 http://dx.doi.org/10.3897/phytokeys.227.102279 journal article http://dx.doi.org/10.3897/phytokeys.227.102279 1314-2003-227-181 28C70019042E5A69ACDEF9F924E8B859 Desmopsis terriflora G.E.Schatz, T.Wendt, Ortiz-Rodr. & Martinez-Velarde sp. nov. Figs 1 , 2 , 3 , 4 , 5 , 6 Type . Mexico . Veracruz , Municipio Uxpanapa , Ejido Progreso Chapultepec , 17°13'58.9"N , 94°18'20.5"W , 105 m , 26 Abril , 2022 (fl,yfr), Ma. F. M. Velarde 72 ( holotype MEXU; isotypes: MO, P) . Diagnosis. Desmopsis terriflora is similar to Stenanona flagelliflora since both species have flowers and inflorescences growing exclusively on flagella. Desmopsis terriflora differs from it by the combination of larger-sized individuals, flowers with rigid petals, food bodies at the base of the inner petals, fused sepals, a greater number of carpels and ovules per carpel, by its monocarps with a hard and woody testa, and its flagella up to 15 meters in length (Table 2 ). Trees , 7-10 m tall, 12-45 cm DBH, bark dark green, verrucose in vivo , dark brown when dry, young branches and terminal shoots golden sericeous. Leaves membranaceous, alternate, distichous, broadly elliptic to oblong-elliptic, 17-31 cm long,4-10 cm wide, base obtuse to rounded, apex acute to acuminate, young leaves golden sericeous on both sides, mature leaves glabrous above and below, venation brochidodromus, 13-18 secondary veins per side, barely elevated to impressed above, raised below, the midrib impressed above but slightly canaliculate toward the base (sometimes with erect to appressed pale brown hairs), raised below and sparsely covered by golden brown hairs, petiole swollen, canaliculate, 5-8 mm long, sparsely covered by golden brown hairs. Inflorescences flagelliflorous, 5-20 woody flagella per trunk, glabrous, shoots emerging from the main trunk from near the base to 2 to 3 m high, then buried in the leaf litter just below the surface (subterranean), to 15 m long, branching; leaves and roots absent, apical parts of flagella greenish and thin, becoming progressively dark and woody toward the base, bearing perennial rhipidia at leafless nodes: the rhipidia terminal but lateral at each node because the flagellum keeps growing by a renewal shoot. Flower bearing part of the generally inflorescence erect, protruding above the leaf litter; Flowers 1 or 2 per inflorescence, flowering pedicels 8-30 mm long, densely covered by golden brown hairs, borne in the axil of a minute, clasping, ovate bract, and bearing a second minute, clasping ovate bract ca. midway, each bract 2 mm long, 2 mm wide, apex acute, outer surface densely covered by golden brown hairs, sepals 3 (rarely 4), valvate, connate at the base, triangular, 3-10 mm long,3-4 mm wide, apex obtuse, outer surface sparsely covered by minute golden brown hairs, glabrous on the inner surface, petals 6 (rarely 8), free, subequal, in two whorls, thick and stiff, pinkish-red, outer petals oblong-lanceolate 13-16 mm long,4-5 mm wide, apex obtuse to acute, outer surface sparsely covered by minute golden brown hairs, essentially glabrous on inner surface, margin ciliate, inner petals oblong-lanceolate, 17-20 mm long, 4-6 mm wide, apex acute, outer surface sparsely covered by minute golden brown hairs, essentially glabrous on inner surface, food bodies (an abrupt thickening) in the basal adaxial side, often with white striations below the food bodies, stamens ca. 30, 1.5-1.7 mm long, the filament 0.3 mm long, thecae 1-1.3 mm long, the anther connective 0.1 mm thick, either expanded discoid or prolonged into a deltoid ligulate appendage bent toward the gynoecium, carpels 6-9, stigmata globose, capitate to napiform, ca. 1 mm in diameter, covered by minute golden brown hairs, ovaries 1.2-1.6 mm long, densely covered by minute golden brown hairs, 1-2 ovules per carpel, lateral. Fruits apocarpous, consisting of 4-8, subsessile, globose monocarps, 1-2 cm in diameter, apex apiculate, base rounded, the longitudinal suture visible (ribbed), stipe up to 1 mm long, exocarp dark reddish to brown, ligneous when mature, endocarp yellow, coconut-scented at maturity. Seeds 1-(2) per monocarp, ellipsoid or rarely discoid, surface slightly rugose, endosperm ruminate (spiniform)1-1.5 cm long,1-1.7 cm wide. Distribution. Desmopsis terriflora is only known to date from the Uxpanapa region (Veracruz state) in southern Mexico (Fig. 2 ). Habitat and ecology. The species occurs in lowland tropical rainforests (100-200 m elevation) on karstic rock formations and on shallow soils, mainly occurring along ravines and river banks, protected from the wind and sun. It forms part of the middle stratum along with species of Amphitecna ( Bignoniaceae ), Dialium ( Fabaceae ), Mortoniodendron ( Malvaceae ) and Terminalia ( Combretaceae ). At the type locality, most individuals were found along a shallow river, and the flagella were all directed downstream and the woody fruits usually float on the water. Phenology. Flowering from April to May; fruiting between May and September. Etymology. The specific epithet " Desmopsis terriflora " refers to its flowers emerging from the ground. Phylogenetic relationships. Desmopsis terriflora is phylogenetically related to Stenanona migueliana , S. morenoi , S. stenopetala , and S. zoque (Fig. 3 ), from which the new species is distinguished by its glabrous leaves ( versus sparsely to densely pubescent), flagelliflorous habit ( versus trunciflorous), the red color of its flowers ( versus pink, yellow and white), the basal fusion of its sepals ( versus totally free sepals), and by the reduced number of ovules (1 to 2) per carpel ( versus several (5 to 10) ovules per carpel) ( Ortiz-Rodriguez et al. 2018 ; Moreno-Mendez and Ortiz-Rodriguez 2020). Additional specimens examined. Mexico , Veracruz , Municipio Minatitlan , Lomas al S. de Poblado 11, ca. 27 km al E de La Laguna , 17°13'45"N , 94°18'30"W , 370 m , 1 April 1981 (fl), T. Wendt , A. Villalobos C. and I. Navarrete 3125 (CHAPA). loc. cit., 14 April 1984 (fl, yng fr), Schatz & Wendt 985 (MO); type locality, abril 2014 (fl, fr), Andres E. Ortiz-Rodriguez 783, 784 (MEXU) .