Research Article |
Corresponding author: Alexandre R. Zuntini ( zuntini@gmail.com ) Corresponding author: Lúcia G. Lohmann ( llohmann@usp.br ) Academic editor: Alan Paton
© 2015 Alexandre R. Zuntini, Charlotte M. Taylor, Lúcia G. Lohmann.
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:
Zuntini AR, Taylor CM, Lohmann LG (2015) Problematic specimens turn out to be two undescribed species of Bignonia (Bignoniaceae). PhytoKeys 56: 7-18. https://doi.org/10.3897/phytokeys.56.5423
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Bignonia comprises 29 species of lianas characterized by eight phloem wedges, leaves usually 2-foliolate, mostly simple tendrils and opaque seed wings. The analysis of herbarium specimens in preparation for a taxonomic revision of the genus led to the recognition of two new species: (i) Bignonia cararensis from Costa Rica, characterized by a thyrse with lateral compound dichasia and lack of interpetiolar ridge, and (ii) Bignonia sanctae-crucis from Bolivia and Brazil, distinguishable by its membranous leaflets, membranous calyx and small fruits. We provide detailed descriptions, illustrations, distribution maps, initial conservation status assessments, and comparisons of the newly described taxa with closely related species.
Amazonia, Costa Rica, Bignoniaceae , Lianas, Neotropical Flora
Bignonia L. is the fifth largest genus in the Neotropical tribe Bignonieae (Bignoniaceae), with 29 species distributed from Argentina to USA (
These two new species are Bignonia cararensis Zuntini from Costa Rica and Bignonia sanctae-crucis Zuntini from Bolivia and western Brazil. Within Bignonia, these new species are not very similar and are not closely related to each other, however, these species are each similar to previously described species.
With these two new species, Bignonia is now composed of 31 species, with no morphological or geographical changes in the circumscription of the genus. Our results highlight the importance of large diverse herbarium collections for understanding the systematics of tropical plants, and also of broadly surveying all the specimens of a group before finalizing monographic studies rather than studying only a selected set of specimens of a given genus.
Specimens from the following herbaria were examined: CR, F, INB, MO, NY, SPF, USJ (acronyms following
Costa Rica. Puntarenas: Reserva Biológica [Parque Nacional] Carara, Sector Quebrada Bonita. Sitio Area administrativa, 09°45.6'N, 084°36.0'W, 20 m, 9 February 1990, R. Zúñiga 90 (holotype: CR-145925, mounted in two sheets!; isotypes: F!, INB!, MO!). Figure
Bignonia cararensis Zuntini A Flowering branch B Gland cluster at leaflet apex on adaxial surface C Calyx D Opened flower E Detail of internal flower base, showing the glandular stipitate trichomes at corolla F Detail of the internal sericeous indument of the corolla lobes G Ovary cross-section H Fruit. Illustrated from Zuñiga 90 (MO) [A–G] and Weinberg s.n. (MO-3842040) [H].
This new species is closely related to Bignonia uleana (Kraenzl.) L.G.Lohmann, but differs by the absence of interpetiolar ridges, inflorescences with compound dichasia (vs. simple dichasia in B. uleana) and fruits up to 14 cm long with cylindrical and delicate spines (vs. longer than 16 cm with triangular and rough spines in B. uleana). Table
Character | B. cararensis | B. uleana |
---|---|---|
Interpetiolar ridge | Absent | Present |
Inflorescence lateral structure | Compound dichasia | Simple dichasia |
Fruit length (cm) | 11.2–14.5 | 16.8–26.0 |
Fruit spines | Cylindrical, moderately distributed | Triangular, sparsely distributed |
Distribution | Costa Rica | Bolivia, Brazil and Peru |
Lianas. Stems solid, cylindrical, not winged, with lenticels, without interpetiolar gland fields, without interpetiolar ridge, puberulous at least at nodes, sparsely lepidote; foliaceous prophylls caducous, cymbiform, ascending, sessile, symmetrical, 1.7–2.0 mm × ca. 1.4 mm, ciliate, sparsely lepidote, without glands; bromeliad-like prophylls present. Leaves 2-foliolate; petiole semi-cylindrical, 35.9–46.5 mm, without simple trichomes or puberulous, sparsely lepidote; petiolules semi-cylindrical, 25.0–45.3 mm, without simple trichomes or puberulous, sparsely lepidote; blades concolorous to slightly discolorous, chartaceous, matte, symmetrical, elliptic to widely elliptic, shortly acuminate apically, rounded basally, 17.1–23.4 × 11.0–12.8 cm, on adaxial surface puberulous at base, sparsely lepidote, with glands clustered at apex and few scattered, on abaxial surface without simple trichomes or puberulous on mid and secondary veins, sparsely lepidote, with a few scattered glands; venation pinnate, with tertiary venations mixed opposite-alternate percurrent; tendrils rarely present, simple, without simple trichomes, sparsely lepidote, with simple apex. Inflorescences thyrses, terminal, multi-flowered, with lateral dichasia compound and pedunculate, without simple trichomes, sparsely to moderately lepidote, primary axis ca. 255.0 mm long; bracts caducous, narrowly triangular, 1.8–2.1 × 0.5–0.6 mm, without simple trichomes, sparsely lepidote, without glands; pedicels 6.7–14.4 mm, without simple trichomes, sparsely lepidote, without glands. Flowers with calyx cupular, 5-toothed, sub-chartaceous, 3.7–5.9 × 4.7–6.4 mm wide at apex, ciliate, moderately lepidote, with a few scattered glands, teeth 0.6–1.4 mm; corolla purple outside, inside color unknown, infundibuliform, dorso-ventrally flattened, membranous, 40.8–75.0 mm, externally sericeous, sparsely lepidote, without glands, internally sericeous at lobes, not lepidote, with stipitate glandular trichomes at base, tube 28.4–52.5 × 2.7–3.3 mm wide at base and 10.9–14.1 mm wide at apex, lobes sub-circular, 9.7–22.0 × 10.7–15.5 mm; androecium didynamous, with stamens included, the largest 16.4–18.6 mm, the shortest 11.2–11.3 mm, without simple trichomes, not lepidote, with stipitate glandular trichomes at base, thecae 3.3–3.5 mm, staminode ca. 4.2 mm; gynoecium 25.5–27.9 mm, ovary cylindrical, verrucose, without simple trichomes, not lepidote, ovules in 2 series per locule, style not lepidote; nectariferous disk reduced. Fruits inflated, narrowly elliptic, 11.2–14.5 × 3.1–4.0 wide × ca. 1.4 cm thick, valves woody, without ridges, moderately echinate, without simple trichomes, not lepidote, without glands; spines cylindrical, 8.2–13.4 mm. Seeds unknown.
Three fertile collections are documented for Bignonia cararensis: a single flowering specimen was collected in February and two fruiting specimens were collected in February and October.
The name is a reference to the type locality.
The collections from the main herbaria of Costa Rica (CR, INB and USJ) were consulted, but so far this species is only documented from Parque Nacional Carara. Since B. cararensis is known exclusively from the type locality, its full distribution cannot be accurately assessed and is here listed as Data Deficient (DD). Additional fieldwork is necessary to estimate the number of mature individuals and to assess the full extend of the species’ distribution.
This species is similar to B. uleana, a species from Bolivia, central western Brazil and Peru. Bignonia cararensis can be recognized by the absence of interpetiolar ridges (vs. present in B. uleana), the inflorescences in lateral compound dichasia (vs. lateral simple dichasia in B. uleana), and the fruit up to 14 cm and with cylindrical delicate spines (vs. longer than 16 cm with triangular rough spines in B. uleana) (Table
The flowering collection Zuñiga 90 was previously identified as Cydista lilacina A.H.Gentry [≡ B. lilacina (A.H.Gentry) L.G.Lohmann] (
In contrast, the fruiting collection Jiménez 2042 was previously identified as Clytostoma pterocalyx Sprague ex Urb. [≡ B. pterocalyx (Sprague ex Urb.) L.G.Lohmann] (in sched. at INB), and as Clytostoma sciuripabulum Bureau & K.Schum. [≡ B. sciuripabulum (Bureau & K.Schum.) L.G.Lohmann] (in sched. at CR and INB). The other fruiting material of this new species (Weinberg s.n.) was also identified as C. sciuripabulum (in sched. at MO). However, Bignonia cararensis differs from B. pterocalyx by its puberulous stems and inflorescences (vs. pilose in B. pterocalyx), 2-foliolate leaves (vs. 1-foliolate in B. pterocalyx) and moderately echinate fruit (vs. densely echinate in B. pterocalyx). Bignonia cararensis differs from B. sciuripabulum by the cylindrical stems (vs. quadrangular in B. sciuripabulum) and apical gland clusters borne on the adaxial leaflet surface (vs. no apical clusters in B. sciuripabulum).
Clytostoma pterocalyx and Cydista lilacina were reported as new records for Costa Rica (
The Carara National Park is located in the northern portion of the Tárcoles-Térraba floristic region, which extends through the central portion of Pacific coastal Costa Rica (
COSTA RICA. Puntarenas: Carara Biological Reserve, 2.6 km del portón de la entrada del sendero Laguna Meandrica. Primer desviación a mano izquierda entrando, 9°48.0'N, 84°35.16'W, 100 m, 6 Apr 2000, L.G. Acosta Vargas 826 (INB, MO); Camino a Coopecarara, 9°47.16'N, 84°36.16'W, 100 m, 11 Oct 1995, Q. Jiménez 2042 (CR, INB); Carara Biological Reserve. 15 minute walk from entrance of Carara taking trail winding right (counter-clockwise), 9°46'N, 84°31'W, 18 Feb 1991, R. Weinberg s.n. (MO-3842040).
Bolivia. Santa Cruz: Prov. Ichilo. El Carmen (8 km al SSW de Buena Vista), tramo de 2km al W de la comunidad por el camino al Campamento del Río Saguayo, 17°31.98'S, 63°41.85'W, 400 m, 5 October 1996, I.G. Vargas C. 5382 & S. Hurtado P. (holotype: MO-5878679!; isotypes: K, NY!). Figure
Bignonia sanctae-crucis Zuntini. A Flowering branch B Stem node with prophylls of the axillary buds C Detail of the abaxial leaflet surface D Calyx E Opened flower F Ovary side-view G Ovary cross-section H Fruit I Seed. Illustrated from Vargas 5382 (NY) [A,D], Saldias 4775 (NY) [E–G] and Nee 52361 (NY) [B, C, H, I].
This new species is similar to Bignonia potosina (K.Schum. & Loes.) L.G.Lohmann, but is distinguished by its membranous leaflets with mixed opposite-alternate percurrent tertiary venation (vs. chartaceous with alternate percurrent tertiary venation in B. potosina), membranous calyx (vs. chartaceous calyx in B. potosina) and fruits shorter than 6.8 cm long (vs. fruits longer than 15 cm in B. potosina). Table
Contrasting characters of Bignonia decora, B. potosina and B. sanctae-crucis.
Character | B. decora | B. potosina | B. sanctae-crucis |
---|---|---|---|
Prophylls of axillary buds | Foliaceous, persistent and spreading | Falcate, caducous and ascending | Falcate, caducous and ascending |
Leaf texture | Sub-chartaceous to chartaceous | Chartaceous to sub-coriaceous | Membranous |
Leaf tertiary venation | Alternate percurrent | Alternate percurrent | Mixed opposite-alternate percurrent |
Inflorescence | Thyrse | Raceme | Raceme |
Calyx texture | Chartaceous | Chartaceous | Membranous |
Fruit length (cm) | 14.7–37.7 | 12.0–24.0 | Ca. 6.8 |
Distribution | Bolivia, Brazil, Ecuador and Peru | Central America | Bolivia and Brazil |
Lianas. Stems solid, tetragonal, winged or ribbed, with lenticels, without interpetiolar gland field, with interpetiolar ridge, puberulous to pilose at least at nodes, sparsely lepidote; foliaceous prophylls caducous, falcate (subulate), ascending, stipitate, asymmetrical, 0.9–2.3 mm × 0.5–1.5 mm, without simple trichomes, sparsely lepidote, with a few glands on abaxial surface (no glands); bromeliad-like prophylls present. Leaves 2-foliolate; petiole semi-cylindrical, (6.1–)15.1–38.9 mm, pubescent, puberulous or pilose, sparsely lepidote; petiolules semi-cylindrical, 9.7–29.8 mm, pilose, sparsely lepidote; blades slightly discolorous, membranous, matte, slightly asymmetrical to asymmetrical, elliptic to widely ovate, acuminate to long acuminate apically, rounded basally (short attenuate), 8.3–13.3(–18.9) × 5.1–8.5(–12.3) cm, on adaxial surface without simple trichomes, densely lepidote, without glands, on abaxial surface pilose along midvein and secondary veins, sparsely lepidote, with a few scattered glands; venation pinnate, with tertiary venations mixed opposite-alternate percurrent; tendrils rarely present, simple, without simple trichomes, sparsely lepidote, with simple apex. Inflorescences racemes, terminal, 2–4-flowered, without simple trichomes or puberulent, sparsely lepidote, primary axis 8.3–13.8 mm long; bracts caducous, not observed; pedicels 5.5–10.0 mm, without simple trichomes, moderately lepidote. Flowers with calyx cupular, 5-toothed, membranous, 4.5–6.0 × 4.3–5.1 mm wide at apex, ciliate, moderately lepidote, with glands clustered in columns, teeth 0.6–1.5 mm; corolla creamish outside, yellowish inside, infundibuliform, dorso-ventrally flattened, membranous, 30.6–52.8 mm, externally pubescent at lobes, moderately lepidote, without glands, internally with pubescent lobes, not lepidote, with shortly stipitate glandular trichomes at base, tube 19.8–40.0 × 2.1–5.0 mm wide at base and 9.2–16.3 mm wide at apex, lobes rounded or oblong, 9.7–15.4 × 8.8–15.2 mm; androecium didynamous, with stamens included, the largest 10.7–18.0 mm, the shortest 6.4–11.7 mm, without simple trichomes, not lepidote, with shortly stipitate glandular trichomes at base, thecae 1.7–3.6 mm, staminode 0.9–2.5 mm; gynoecium 21.5–29.2 mm, ovary ovoid to cylindrical, smooth, without simple trichomes (pilose at apex), densely lepidote, ovules in 4 series per locule, style sparsely lepidote at base; nectariferous disk reduced. Fruits inflated, oblong, ca. 6.8 × 2.8 wide × 0.8 cm thick, valves woody, without ridges, smooth, without simple trichomes, sparsely lepidote, without glands. Seeds beige, thin, transversally elliptic to narrowly transversally oblong, symmetrical, 13.7–24.3 × 28.5–39.4 mm, with two opaque wings; seed body flattened, 0.8–1.2 mm thick.
This species is found in evergreen or semideciduous forests in Western Amazonia, occurring in Bolivia (Beni, La Paz and Santa Cruz) and Brazil (Acre, Amazonas and Mato Grosso), between 160 to 700 m alt. (Fig.
This species was collected with flowers in June, September, October and November. A single fruiting specimen was collected in July.
Bignonia sanctae-crucis is known from only seven locations but is considered Least Concern (LC) given its wide extent of occurrence (over 600.000 km2) and the different physiognomies where it occurs, including secondary formations. The number of locations where this species is known to occur is likely underestimated because Bignonia species are usually not densely distributed and because this entire region is not well documented floristically. Additional fieldwork is needed in order to fully document the extent of distribution of this species.
The epithet refers to the type locality, the Department of Santa Cruz (Bolivia), where most specimens were collected.
Bignonia sanctae-crucis and B. potosina share quadrangular and ribbed (winged) stems, prominent interpetiolar ridges, falcate and caducous prophylls, and few-flowered racemes. Apart from being morphologically similar, these species are also closely related and can be confused. However, Bignonia sanctae-crucis can be distinguished from B. potosina by the membranous calyx (vs. chartaceous in B. potosina) and fruits shorter than 6.8 cm long (vs. fruits longer than 15 cm in B. potosina) (Table
The only fruiting material of this new species (Nee 52361) was previously identified as Cydista cf. decora (S.Moore) A.H.Gentry [≡ B. decora] (in sched. at NY), a closely related species. The flowering specimens of B. sanctae-crucis, however, were identified as Clytostoma sciuripabulum Bureau & K.Schum. [≡ B. sciuripabulum], Clytostoma uleanum Kraenzl. [≡ Bignonia uleana], and some other Clytostoma species (in sched. at MO and NY). The thin-textured corolla probably confused the generic identification, given that most Cydista, as previously circumscribed, were characterized by thicker corollas whereas such thin corollas were characteristic of the previously recognized Clytostoma. Despite its corolla texture, B. sanctae-crucis is not closely related to the species that were included in Clytostoma, and does not have the verrucose glabrous ovary that is characteristic of that group.
BOLIVIA. Beni: Rurrenabaque, Rurrenabaque, 14°28'S, 67°34'W, 333 m, 8 Oct 1921, White 874 (NY). La Paz: Alto Beni, Concesión de San Jose de Papay, 15°02'S, 67°33'W, 500 m, 23 Oct 1987, E. Vargas 2022 (LPB, MO); San Buena Ventura, 500 m, 29 Nov 1901, R.S. Williams 363 (NY). Santa Cruz: Cercado, Lomas del Rio Cúcha, 450 m, 28 Oct 1925, J. Steinbach G. 7307 (F, MO); Ibáñez, Gorge of Río Bermejo, 6.5km (by road) W of the checkpoint at Angostura, 18°10'S, 63°33'W, 690 m, 25 Jul 2003, M.H. Nee 52361 (LPB, NY, USZ). Ichilo, 2 km W of Center of San Carlos, older secondary growth along highway from Buena Vista to Villa Tunari, 17°24.5'S, 63°45'W, 310 m, 31 Oct 1999, M.H. Nee 50398 (NY); Ichilo, Estáncia San Rafaél (propiedad de la Unversidad NUR), 16 km SW de Buena Vista, 17°36'S, 63°36'W, 432 m, 1 Oct 1996, M. Saldias P. 4775 (NY, USZ). BRAZIL. Acre: Tarauacá, 1–3 km east of Rio Tarauacá, 24 Sep 1968, G.T. Prance 7513 (K, INPA, MG, MO, NY). Amazonas: Envira, Rio Juruá, Basin of Rio Jurua, near mouth of Rio Embira, 7°30'S, 70°15'W, 160 m, 28 Jun 1933, B.A. Krukoff 5046 (MICH, MO, NY, US). Mato Grosso: Barra do Bugres, Fazenda Ochsenfeld, 23 Oct 1995, G. Hatschbach 63777 (MBM, SPF).
We are grateful to Barbara Alongi for preparing the illustrations of the newly described taxa, and for the staff from all the herbaria cited herein for materials on loan, especially F and NY. This paper is part of the PhD dissertation of ARZ, which was funded by the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) through two scholarships to ARZ (2011/09160-5 and 2013/08657-9). We thank FAPESP for a research grant to LGL (2011/50859-2) and a collaborative Dimensions of Biodiversity-Biota grant funded by FAPESP (2012/50260-6), NASA & NSF. We also thank CNPq for a Pq-1C grant to LGL (307781/2013-5).