Celtis flumeniana Zamengo, 2023

Zamengo, Henrique Borges, Gaglioti, André Luiz & Pederneiras, Leandro Cardoso, 2023, Celtis flumeniana (Cannabaceae): a new species from Brazil and reestablishment of Celtis alnifolia, Phytotaxa 620 (4), pp. 251-263 : 253

Celtis flumeniana Zamengo sp. nov. ( Figures 1–5 ).

Type:— Brazil. Goiás: Cavalcante , V„o do Moleque, Comunidade Kalunga , Mata Passo, Fazenda Congonhas , nas margens do Rio Paran„ , 13°11’31.0”S, 47°32’16.4”W, 4 March 2023, fr., H.B.Z. Souza et al. 229 (holotype RB: herbarium number 846999, barcode number 01484814; isotypes IAC, K, MBM, MO, NY, P, PMSP, R, SP, SPF, US). The paratypes are in Appendix 1.

Common names: —Juá, juá mirim, juazeiro, and lim„ozinho.

Diagnosis: —Among the Celtis species, C. flumeniana is morphologically similar to C. chichape since they are shrubby habit, straight or semi-curved spines, leaves elliptic, widely-elliptic, widely-ovate to ovate, leaves surfaces subglabrous, smooth to the touch, pistillate flowers with ovary smooth to the touch, and drupes orange. Despite these similarities, C. flumeniana differs by presenting: trunk surface scaly vs fissured ( C. chichape ); style null vs inconspicuous 0.1–0.5 ( C. chichape ); pyrene ovate vs circular ( C. chichape ), pyrene mono to biapiculate vs absent ( C. chichape ), apiculum scar present vs absent ( C. chichape ) and pyrene surface verrucose vs alveolate-crateriform ( C. chichape ).

Description: —Shrubs or scandent trees, 2–10 m height, bark scaly, branches buff or fawn in natura or in sicco, sinuous, entire, subglabrous to pilose, trichomes ivory in natura or in sicco; armed branches, stipular spines not forming brachyblast, 2–11 mm length, in pairs or solitary, straight or semi-curved, stramineous in natura or in sicco, glabrous to subglabrous, trichomes ivory in natura or in sicco scarce both at the base and on the entire surface of the spines. Petiole 4–7 mm length, pilose, trichomes ivory in natura or in sicco, leaves elliptic, widely-elliptic, widely-ovate to ovate, 3.5–8 × 2–5 cm, chartaceous to membranaceous in sicco, apex cuspidate, obtuse to rounded, base obtuse to subcordate, margins serrate, teeth congested emerging from the lower third to the upper third, from the middle to the upper third and/or restricted to the upper third, surfaces concolorous (both emerald to olive in natura or in sicco), adaxial surface opaque or shiny, glabrous to subglabrous, trichomes ivory concentrated on the veins and scarce on the laminar surface, adaxial surface smooth to the touch in sicco, veins protruding, buff, chestnut to lemon in natura or in sicco, contrasting or not in relation to the abaxial surface, domatias in pockets, conspicuous, glabrous to pilose, trichomes ivory in natura or in sicco, ciliate. Peduncles 4–8 mm length, subglabrous to pilose, ivory trichomes in natura or in sicco, without bracts, arranged flowers on dichotomous cymes. Staminate flowers with pedicels 0.5–1 mm length, subglabrous to pilose, trichomes ivory in natura or in sicco, without bracts, sepals with dorsum subglabrous, trichomes ivory in natura or in sicco, margins entire. Pistillate flowers with pedicels 0.5–1 mm, subglabrous to pilose, trichomes ivory in natura or in sicco, ovary 2–2.5 × 1–1.5 mm, glabrous to subglabrous, trichomes ivory in natura or in sicco scarce both at the base and on the surface of the ovary, ovary surface smooth, style null, stigmate branches sessile, 1–2 mm length, stigmate lobes bifid (1–1.5 mm deep incisions). Pedicels of drupes with 2.5–3.5 mm length, glabrous to subglabrous, trichomes ivory in natura or in sicco, mature drupes orange in natura, 4.5–7.5 × 3.5–5 mm, epicarp glabrous to subglabrous, trichomes ivory in natura or in sicco scarce both at the base and on the surface of the epicarp, epicarp surface smooth, sepals deciduous at the base, mesocarp not viscous, membranous, not ornamented, pyrene ivory in natura or in sicco, ovate, 4.5–5 × 2.5–3 mm, mono or biapiculate, apiculum aciculate, 0.5–1 mm length, ridge linear, apiculum scar present, pyrene surface verrucose, rounded warts randomly distributed.

Etymology: —The epithet “ flumeniana ” was chosen in allusion to the area of occurrence of the species, as all its records associate it with places close to rivers.

Phenology: —Flowering starts in October and lasts until November, and the fruits start to appear in October and last until July of the next year.

Distribution and habitat: —Endemic to Brazil, generally found in the Cerrado biome with only two records for the Amazon biome ( Fig. 4 A ). Most records associate C. flumeniana with areas of “Capoeirıes” (secondary vegetation composed of grasses and sparse shrubs and trees) and riparian forests composed of sandy, sandy-clay, and gravelcovered soils ( Fig. 4 B ). The type specimen was collected on the banks of the Paran„ River ( Fig. 4 C, D ), on flat ground with sandy soil that occasionally gets flooded due to the river’s flooding.

Conservation status: — Celtis flumeniana is known from only seventeen collections, made between 1907 and 2023. Nevertheless, the extent of occurrence of C. flumeniana is ca. 815,623 km 2. Its population sizes are unknown and further surveys are needed to assess its area of occupancy. For these reasons C. flumeniana is assessed as Data Deficient (DD) according to IUCN Red List criteria ( IUCN 2022).

Taxonomic notes: — Celtis flumeniana is a new member of C. subg. Mertensia ser. Eumomisia Planchon. Members of this series are characterized by the presence of spines, pistillate flowers with bifid stigmatic lobes, and with a distribution restricted to the Neotropical region ( Planchon 1848, 1873).

Figures

FIGURE 1. Main characteristics of Celtis flumeniana Zamengo.—A. Habit. B. Trunk. C. Leaf, abaxial surface. D. Domatia. E. Cyme. F. Staminate flower. G. Pistillate flower. H. Immature drupes. I. Mature drupe. J. Pyrenes. J1. Monoapiculate pyrene. J2. Biapiculate pyrene.

FIGURE 2. Illustration of Celtis flumeniana Zamengo.—A. Fruit branch. B. Adult leaf. C. Domatia. E. Staminate flower. F. Pistillate flower. G. Drupe. H. Pyrene. Illustrator Klei Sousa.

FIGURE 3. Holotype of Celtis flumeniana Zamengo.

FIGURE 4. Distribution map and areas of occurrence of Celtis flumeniana Zamengo.—A. Distribution map, Brazilian states, Goiás (GO), Maranh„o (MA), Mato Grosso (MT), Pará (PA), and Tocantins (TO). B. Banks of the Paran„ River. C. Paran„ River. D. Collection on the banks of the Paran„ River.

FIGURE 5. Morphological differences between C. alnifolia, C. chichape, C. flumeniana, and C. iguanaea.—A: C. alnifolia, trunk.; B: C. chichape, trunk.; C: C. flumeniana, trunk.; D: C. iguanaea, trunk.; E: C. alnifolia, staminate flower.; F: C. chichape, staminate flower.; G: C. flumeniana, staminate flower.; H: C. iguanaea, staminate flower.; I: C. alnifolia, pistillate flower.; J: C. chichape, pistillate flower.; K: C. flumeniana, pistillate flower.; L: C. iguanaea, pistillate flower.; M: C. alnifolia, mature drupe.; N: C. chichape, mature drupe.; O: C. flumeniana, mature drupe.; P: C. iguanaea, mature drupe.; Q: C. alnifolia, pyrene.; Q1: C. alnifolia, arrow pointing to the apiculum scar.; R: C. chichape, pyrene.; S: C. flumeniana, pyrene.; S1: C. flumeniana, arrow pointing to the apiculum scar.; T: C. iguanaea, pyrene. T1: C. iguanaea, arrow pointing to the apiculum scar.