Research Article |
Corresponding author: Andrés Ernesto Ortiz-Rodriguez ( ortizrodriguez.ae@gmail.com ) Academic editor: M. Alejandra Jaramillo
© 2023 María Fernanda Martínez-Velarde, Carlos Rodrigues-Vaz, Vincent Soulé, Francis J. Nge, George E. Schatz, Thomas L. P. Couvreur, Andrés Ernesto Ortiz-Rodriguez.
This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Citation:
Martínez-Velarde MF, Rodrigues-Vaz C, Soulé V, Nge FJ, Schatz GE, Couvreur TLP, Ortiz-Rodriguez AE (2023) Desmopsis terriflora, an extraordinary new species of Annonaceae with flagelliflory. PhytoKeys 227: 181-198. https://doi.org/10.3897/phytokeys.227.102279
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Flagelliflory refers to the production of inflorescences exclusively on long, whip-like branches which emerge from the main trunk and extend along the ground or below it. It is the rarest type of cauliflory and only a few cases have been reported in the world. Here, a new species of Annonaceae with flagelliflory is described and illustrated. The phylogenetic relationships of the new species were inferred using a hybrid-capture phylogenomic approach and we present some notes on its reproductive ecology and pollen characteristics. The new species, namely Desmopsis terriflora sp. nov., is part of a clade composed of Mexican species of Stenanona with long, awned petals. Desmopsis terriflora is distinguished by its flageliflorous inflorescences, basely fused sepals, thick red petals, reduced number of ovules per carpel, pollen grains with a weakly rugulate to fossulate exine ornamentation, and its globose, apiculate fruits with a woody testa. The morphological characteristics of the flagella suggest that these are specialized branches rather than inflorescences, and the absence of ramiflory implies an exclusively reproductive function. The flowers are infrequently visited by insects, their potential pollinators being flies and ants.
Anatomy, Cauliflory, Mexico, phylogeny, tropical rain forest
Cauliflory is the general term used to refer to the production of inflorescences along the main trunk and on leafless branches of woody plants (
Desmopsis terriflora G.E.Schatz, T.Wendt, Ortiz-Rodr. & Martínez-Velarde A multiple flagella emerging from the base of the main trunk B flagella lying on the rocky ground C, D lateral inflorescences on the flagellum E flower in anthesis F monocarps G male flower releasing pollen H female flower.
Flagelliflory is a very rare phenomenon in nature and has been documented in ca. 20 tree species, most belonging to the Annonaceae and Moraceae families and restricted to the tropical forests of Asia, Africa, Mexico and South America (
In Mesoamerica (southern Mexico and Central America), flagelliflory has been documented in just one species of Annonaceae restricted to the karst forests of southern Mexico: Stenanona flagelliflora T.Wendt & G.E.Schatz (
Comparison of diagnostic morphological characters of the unpublished name “Uxpanapanona flagellaris” (
Characters | “Uxpanapanona” | Desmopsis | Sapranthus | Stenanona |
---|---|---|---|---|
Number of petals | 6, rarely 8 | 6 | 6 | 6, rarely 8 |
Number of sepals | 3, rarely 4 | 3 | 3 | 3, rarely 4 |
Petals texture | Stiff and thick | Stiff and thick | Thin and fleshy | Thin and fleshy |
Colour of petals | Red | Yellow, greenish or rarely white | Red to purple, rarely yellow or green | Red to purple, rarely yellow or white |
Fused petals | No | No | No | No, rarely yes |
Fused sepals | Yes, basely | Yes, basely | No | No, rarely yes |
Food bodies | Present | Absent, rarely present | Present | Absent |
Number of ovules per carpel | 1 or 2 | 1 or 2, rarely several | Several | several, rarely 1 or 2 |
Leafy bracts | Absent | Present, rarely absent | Present, rarely absent | Absent |
Monocarps shape | Globose | Globose | Cylindrical | Cylindrical |
Wall of monocarps | Thick | Thin | Thick | Thick |
Seeds ruminations | Spiniform | Peg-shaped | Lamelate | Spiniform |
Pollen grains aperture | ? | Disulcate | Disulcate | Inaperturate |
Here, we carried out botanical explorations in Uxpanapa, Veracruz Mexico with the aim of finding individuals of this new species, documenting some aspects of its reproductive ecology, phylogenetic position and to describe it formally.
Field explorations to find the new flagelliflorous species were carried out in the region of Uxpanapa, Veracruz, Mexico (Fig.
Based on the field notes of only one of the two collections, the species should occur around “El Poblado 11” (currently named Helio Garcia Alfaro) where it was collected in 1981 by Thom Wendt. Our first explorations around Poblado 11 were unsuccessful; the vegetation surrounding the town is very fragmented and consists of secondary vegetation. A community-led protected forest area in front of Poblado 11 offered a better chance of finding the species (Fig.
The phylogenetic relationships of the new species were inferred using a hybrid-capture phylogenomic approach. Representatives of the genera Desmopsis, Sapranthus, Stenanona and Tridimeris, as well as some representatives of the Miliuseae tribe were included to assess the taxonomic status of this flagelliflorous species at the genus level (Suppl. material
The Annonaceae baiting kit (
Phylogenetic relationships among taxa were estimated using maximum likelihood (ML) methods performed with RAxML (
We analysed the pollen of the new species using scanning electron microscopy (SEM) at the Photography and Microscopy of the Biodiversity Laboratory 1, Universidad Nacional Autónoma de México (
Flower phenology was documented to determine the timing of the onset of stigmatic receptivity, its duration and the start and duration of the staminal phase (see
The ASTRAL and the ML (Fig.
Maximum likelihood tree (RaxML) of the Neotropical clade of Miliuseae (subtribe Sapranthinae) based on 323 Annonaceae wide exons and with emphasis on the species of Stenanona Standl. and Desmopsis Saff. Darker circles indicate strongly supported clades (bootstrap values greater than 90 and Posterior Probabilities greater than 9.0). The shaded clade includes the new species.*= flagelliflorous species. In the photo, a flower of Desmopsis terriflora emerging from the ground is shown.
Pollen grains of the new species are solitary, symmetrical, and ellipsoid, with two depressed germinative zones and are inaperturate. The grains are 40–45 μm long, 30–40 μm wide, with a weakly rugulate to fossulate (-perforate) exine ornamentation (Fig.
Scanning electron microscopy (SEM) images of pollen grains A Desmopsis terriflora G.E.Schatz, T.Wendt, Ortiz-Rodr. & Martínez-Velarde, pollen grain without externally visible aperture(s) B exine sculpturing weakly rugulate to fossulate (-perforate) ornamentation C Desmopsis trunciflora (Schltdl. & Cham.) G.E.Schatz, pollen grain showing one (another one at the opposite side likely to be also present) aperture exine area D exine sculpturing weakly rugulate to fossulate (-perforate) ornamentation E Stenanona tuberculata G.E. Schatz & Maas, pollen grain without externally visible aperture(s) F exine sculpturing verrucate ornamentation.
The individuals of the new species were in full bloom during the observation period (April). All the individuals with flagella had inflorescences at different stages of development (36 ± 12.69 inflorescences per flagellum in 10 measured individuals). The number of flagella (7.7± 4.9 flagella per trunk) is positively correlated with the diameter of the main trunk (r2 = 51, p < 0.05). The length of the flagella (8 ± 4.0 m) is not directly associated with the diameter of the main trunk (r2 = 33, not significant), while the number of inflorescences is positively correlated to the length of the flagellum (r2 = 49, p < 0.05). The flowers were markedly protogynous, with the entire extent of reproductive activity restricted to a 27 hour-period. The pistillate phase lasted for 4–5 h. from ca. 1400 hours to 1800–1900 hours of a first day (Fig.
Timing of phenological events and visitor activity during sexually functional phases of Desmopsis terriflora flowers. The pistillate phase occurs between 1400 hours and 1800–1900 hours of the day, during this phase the floral visitors (light green: flies, blue: ants) are attracted by the strong banana-like odor in the flowers. The pistillate phase is succeeded by a long interim period of 11–12 h, during which the flowers were not sexually functional, neither floral scent dissipated, nor floral visitors observed. The staminate phase occurs between 1200–1300 hours of the second day, during which there is an obvious increase in floral scent and visitors are again attracted. Note that the beetles (dark green) are only present in the staminate phase.
Throughout flower anthesis, low diversity and abundance of floral visitors were observed (9 insects’ observations in 27 hrs, 1 to 4 insects per observation). Floral visitors were insects from three main groups, flies, beetles, and ants. Flies were observed most often (7/9), followed by ants (5/9) and beetles (4/9) (Suppl. material
The new species described here was suggested more than 35 years ago (
Flagelliflory is rare phenomenon in nature and its presence in different lineages of angiosperms suggests an independent origin (
Morphological features of Desmopsis terriflora G.E.Schatz, T.Wendt,Ortiz-Rodr. & Martínez-Velarde compared to those of Stenanona flagelliflora T.Wendt & G.E.Schatz.
Features | Stenanona flagelliflora | Desmopsis terriflora |
---|---|---|
Size | Up to 2 m tall | up to 10 m tall |
Leaves length | Up to 18 cm | up to 31 cm |
Sepals | Free | Fused |
Outer petals size | 13–14 mm long | 13–16 mm long |
Pedicels | 4–7 mm long | 8–30 mm long |
Food bodies | Absent | Present |
Number of carpels | Up to 6 | 6–9 |
Ovules per carpel | 1 | 1–2 |
Flagella length | Up to 3 m long | Up to 15 m long |
Monocarps | Ellipsoid, thin wall | Globose, thick wall |
Our results on the reproductive ecology of Desmopsis terriflora suggest that flowers on flagella present a depressed visitation rate (low frequency and diversity of floral visitor), probably linked to the fact that the species has a very narrow distribution and is rare in the locality studied (
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).
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
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.
Desmopsis terriflora is only known to date from the Uxpanapa region (Veracruz state) in southern Mexico (Fig.
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.
Flowering from April to May; fruiting between May and September.
The specific epithet “terriflora” refers to its flowers emerging from the ground.
Desmopsis terriflora is phylogenetically related to Stenanona migueliana, S. morenoi, S. stenopetala, and S. zoque (Fig.
Mexico, Veracruz, Municipio Minatitlán, 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).
We extend our sincere gratitude to Héctor Gómez Dominguez, for his valuable support during the field trip and to Paul J.M. Maas, Adriana Lobão and Michael Pirie for their encouraging and constructive comments on the manuscript. Thanks to Christopher Davidson and Sharon Christoph for financing visits to the type locality through the project “KarstBio”. Also we thank Leopoldo Hurtado for his support during the preparation of Fig.
No conflict of interest was declared.
No ethical statement was reported.
No funding was reported.
MFMV, TLPC and AEOR conceived the ideas, CR, VS conduct the species sampling and laboratory work, FN, MFMV and AEOR analysed the data, MFMV and AEOR wrote the main manuscript text, GES reviewed the manuscript. All authors read and approved the final version.
María Fernanda Martínez-Velarde https://orcid.org/0000-0001-9022-9658
Carlos Rodrigues-Vaz https://orcid.org/0000-0002-4263-3573
Vincent Soulé https://orcid.org/0009-0001-3910-2317
Francis J. Nge https://orcid.org/0000-0002-0361-8709
Thomas L. P. Couvreur https://orcid.org/0000-0002-8509-6587
Andrés Ernesto Ortiz-Rodriguez https://orcid.org/0000-0003-4583-6701
All of the data that support the findings of this study are available in the main text or Supplementary Information.
Total number of flower visits per hour
Data type: image (PDF file)
Explanation note: The fitted number of visits (in original scale) according to the results of the GLM analysis.
Country of origin and voucher information of the species used in the phylogenetic analyses
Data type: table (word document)