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Prosthechea tinukiana sp. nov. (Orchidaceae: Laeliinae): An update of the Prosthechea prismatocarpa complex

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We describe and illustrate a new species of Prosthechea from Costa Rica. The species is similar to Prosthechea ionocentra, but it is easily distinguishable by its inflorescence originating from the penultimate mature pseudobulb; its purple spotted sepals and petals; the cordate, acute labellum; the disc with two longer, narrower keels; the stigmatic arms of the column, which are convergent and rounded; and the narrower stigma. Differences from other related species are given and discussed. Data on distribution, habitat and ecology, etymology, and phenology are provided. An updated key to the species of the Prosthechea prismatocarpa complex is presented.
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http://journals.tubitak.gov.tr/botany/
Turkish Journal of Botany
Turk J Bot
(2015) 39:
© TÜBİTAK
doi:10.3906/bot-1408-38
Prosthechea tinukiana sp. nov. (Orchidaceae: Laeliinae): an update of the
Prosthechea prismatocarpa complex
Diego BOGARÍN1,2,*, Adam P. KARREMANS1,3
1Lankester Botanical Garden, University of Costa Rica, Cartago, Costa Rica
2Herbarium UCH, Autonomous University of Chiriquí, Chiriquí, Panama
3Naturalis Biodiversity Center, Leiden University, Leiden, Netherlands
* Correspondence: diego.bogarin@ucr.ac.cr
1. Introduction
Prosthechea Knowles & Westc. comprises 24 species in
Costa Rica and about 100 species ranging from Florida
southward through Central America and the Antilles
down to Argentina (Higgins, 2003; Withner and Harding,
2004; Mó et al., 2014). e genus was resurrected by
Higgins (1998), who proposed a broad concept of
Prosthechea, segregating it from the well-known genus
Encyclia Hook. to embrace species variously treated at
some point under the generic concepts of Anacheilium
Rchb.f. ex Homanns., Coelogyne Lindl., Epidendrum L.,
Epithecia Knowles & Westc., Hormidium Lindl. ex Heynh.,
and Microstylis (Nutt.) Eaton (Pupulin, 2004).
In their treatment of Prosthechea, Withner and Harding
(2004) proposed a separate genus with the name Panarica
Withner & Harding for the species belonging to the
Prosthechea prismatocarpa (Rchb.f.) W.E.Higgins complex.
ey based their characterization mainly on Pupulin
(2002), who recognized the P. prismatocarpa complex by
the pyriform, 2- to rarely 3-leaved pseudobulbs; the showy
owers produced on long, erect inorescences; the usually
3-lobed lip (entire in P. brassavolae (Rchb.f.) W.E.Higgins)
with the median lobe larger than the lateral lobes, acute
to attenuate; and the column provided with large lateral
teeth with a deep sinus and a median mbriate tooth. With
the exception of P. brassavolae, ranging from Oaxaca and
Veracruz in Mexico to western Panama and its closely
allied P. mulasii Soto Arenas & L.Cerv., from Guerrero,
Mexico, the group is restricted to Costa Rica and western
Panama.
Panarica, as most other segregates of Prosthechea, has
received little support as a distinct genus (Higgins, 2005;
Pupulin and Karremans, 2007; Higgins, 2008; Karremans,
2009; Mó et al., 2014). Nonetheless, the species of the
P. prismatocarpa complex form a natural and easily
recognized group to which the species here described can
be added.
2. Materials and methods
is study was performed at the Lankester Botanical
Garden (JBL), University of Costa Rica, and Cerro
Tinuk at the Cordillera de Talamanca (9°1729.1N,
83°1011.2W). Living specimens were gathered,
cultivated, and documented at JBL between 2012 and
2014. Georeferences for specimens were obtained using
a Garmin eTrex Vista GPS, Google Earth Pro 6.1.0, and
eld observations. Ecological zones were estimated by
using the Holdridge Life Zone System (Holdridge, 1967,
1987) and the ecological map of Costa Rica (Bolaños et
al., 2005). Phenology data were recorded both in the
eld and for cultivated specimens. Individual plants were
photographed, illustrated, and preserved as herbarium
specimens and spirit specimens in formaldehyde:
acetic acid: ethanol [FAA (53% ethanol, 37% water,
Abstract: We describe and illustrate a new species of Prosthechea from Costa Rica. e species is similar to Prosthechea ionocentra,
but it is easily distinguishable by its inorescence originating from the penultimate mature pseudobulb; its purple spotted sepals and
petals; the cordate, acute labellum; the disc with two longer, narrower keels; the stigmatic arms of the column, which are convergent
and rounded; and the narrower stigma. Dierences from other related species are given and discussed. Data on distribution, habitat and
ecology, etymology, and phenology are provided. An updated key to the species of the Prosthechea prismatocarpa complex is presented.
Key words: Costa Rica, Cerro Tinuk, Panarica, paramo, new species, Talamanca, taxonomy
Received: 20.08.2014 Accepted: 21.11.2014 Published Online: 00.00.2015 Printed: 00.00.2015
Research Article
BOGARÍN and KARREMANS / Turk J Bot
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5% formaldehyde, and 5% glycerol)] (only including
owers) for future reference. Whenever possible, the
herbarium specimens were complemented with sketches,
photographs, and FAA material. e material preserved
in FAA was deposited at JBL. Sketches and images were
prepared from living specimens with a Leica MZ9.5
stereomicroscope with drawing tube, Nikon D5100 digital
camera with AF-S VR Micro-NIKKOR 105mm f/2.8G
IF-ED lens, and Epson Perfection Photo Scanner V600.
Composite plates were diagrammed in Adobe Photoshop.
Ink drawings were prepared on smooth Fabriano paper of
240 g/m2 with a Rotring Rapidograph 0.1 mm using black
capillary cartridges and traced in Artograph LightPad
A920. Descriptions were prepared both from living
specimens and data taken in the eld.
3. Results
3.1. Taxonomic treatment
Prosthechea tinukiana Bogarín & Karremans, sp. nov.
(Figures 1–5)
Figure 1. Prosthechea tinukiana. A- Habit. B- Flower. C- Perianth, attened. D- Column and lip, side view. E- Lip. F- Column, front and
side views. G- Pollinarium and anther cap. Drawn from the holotype by L. Oses.
BOGARÍN and KARREMANS / Turk J Bot
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Figure 2. Lankester composite dissection plate (LCDP) of Prosthechea tinukiana. A- Habit. B- Flower. C- Perianth, attened.
D- Column and lip, side view. E- Lip. F- Column, front and side views. G- Pollinarium and anther cap. Photographs and scans
from the holotype by D. Bogarín.
BOGARÍN and KARREMANS / Turk J Bot
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Figure 3. Comparison of owers among the Costa Rican species of the P. prismatocarpa complex. A- P. neglecta (G. Villalobos
s.n.). B- P. prismatocarpa (Z. Serracín s.n.). C- P. tardiora (J.J. Zúñiga s.n.). D- P. tinukiana (D. Bogarín 9723). E- P. ionocentra (D.
Bogarín 5213). F- P. brassavolae (JBL-03512). Scale bar = 3 cm.
Figure 4. Comparison of labella among the Costa Rican species of the P. prismatocarpa
complex. A- P. neglecta (G. Villalobos s.n.). B- P. prismatocarpa (Z. Serracín s.n.). C-
P. tardiora (J.J. Zúñiga s.n.). D- P. tinukiana (D. Bogarín 9723). E- P. ionocentra (D.
Bogarín 5213). F- P. brassavolae (JBL-03512). Scale bar = 1 cm.
Figure 5. Comparison of the ventral view of the column among the Costa Rican species
of the P. prismatocarpa complex. A- P. neglecta (G. Villalobos s.n.). B- P. prismatocarpa
(Z. Serracín s.n.). C- P. tardiora (J.J. Zúñiga s.n.). D- P. tinukiana (D. Bogarín 9723).
E- P. ionocentra (D. Bogarín 5213). F- P. brassavolae (JBL-03512). Scale bar = 1 cm.
BOGARÍN and KARREMANS / Turk J Bot
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Typ e : Costa Rica, Puntarenas: Buenos Aires, Buenos
Aires, Olán, cumbre del Cerro Tinuk, 9°1729.1N,
83°1011.2W, 2412 m, bosque pluvial premontano,
terrestre en bosque de páramo, 25.06.2012, D. Bogarín
9723, E. Herrera, D. Jiménez, A.P. Karremans & V.H.
Zúñiga (holotype, JBL; isotypes, CR, USJ).
Diagnosis: e species is similar to Prosthechea
ionocentra (Rchb.f.) W.E.Higgins; it diers mainly in the
inorescence always developed from the penultimate
mature pseudobulb; the purple spotted sepals and petals;
the cordate and acute labellum; the disc with two longer,
narrower keels; the convergent, rounded stigmatic arms of
the column; and the narrower stigma.
Description: Plant lithophytic or terrestrial, up to
40 cm tall, forming large groups of individuals, with
elongate rhizome covered by papyraceous, brown bracts;
the internodes to 4 cm long. Roots exuous, glabrous, to
3 mm in diameter. Pseudobulbs pyriform, ovoid, laterally
complanate, elongate, to 13.5–15.0 × 3.3–3.4 cm, 2-foliate
at apex. Leaves separated by an internode to 2 cm long,
oblong-elliptic, coriaceous, conduplicate, acute, retuse,
narrowed to a conduplicate; subsessile, 18.8–20.0 × 5.0–
6.2 cm. Inorescence terminal, racemose, emerging from
a papery spathe to 11.2 cm long, developed from the apex
of the penultimate mature pseudobulb, to 17 cm long
including the peduncle, rachis 6 cm long, many-owered
(up to 9 owers). Ovary prismatic, pedicellate, about 2.2
cm long including the pedicel. Flowers relatively large,
to 7.5 cm in diameter, showy, with sepals and petals free,
spreading, the margins reexed, yellowish, nely spotted
with dark purple, the lip basally white, with a rose-purple
stain from the middle to the apex. Dorsal sepal oblong-
elliptic, acute to acuminate, 3.8 × 0.4 cm. Lateral sepals
oblong-elliptic, acute, subcarinate, 3.6 × 0.6 cm. Petals
basally subfalcate, narrowly lanceolate, acute, 3.4 × 0.4 cm.
Lip 3-lobed, shortly clawed, basally adnate to the column,
3.2 × 1.3 cm, the lateral lobes oblique, truncate, slightly
reexed; the midlobe cordate, concave, acute; disc with a
callus formed by 2 eshy keels converging near the middle
and diverging at apex. Column stout, semiterete, 1.4 × 0.5
cm, with a pair of eshy, lateral teeth, and a central, erose
lobe above the anther. Anther incumbent, operculate,
subspherical, 4-celled. Stigma ventral, cordate. Pollinia 4,
waxy, fusiform, with linear caudicles.
Distribution: Known only from the type locality on
Cerro Tinuk in the Cordillera de Talamanca, Costa Rica.
Etymology: Named aer Cerro Tinuk where the only
known populations of this species were observed. Tinuk is
probably an indigenous word, but we were unable to nd
its meaning.
Ecology: Cerro Tinuk is located in front of the
paramo of Cerros Utyum in the Cordillera de Talamanca.
e slopes of the hill are covered by primary oak forest.
At the summit and above the continuous timberline,
there is a small plateau of isolated dwarf vegetation.
Some common species on the top are shrubs of Budlejja
nitida (Loganiaceae), Pernettya sp., Satyria sp., and
Vaccinium spp. (Ericaceae), and herbs of Alchemilla spp.
(Rosaceae), Castilleja sp. (Schrophulariaceae), Cortaderia
sp. (Poaceae), Fuchsia spp. (Onagraceae), Gamochaeta sp.
(Asteraceae), Hypericum spp. (Clusiaceae), Lycopodium sp.
(Lycopodiaceae), Maianthemum gigas (Convallariaceae),
and Nertera granadensis (Rubiaceae) and lichens among
others. Interestingly, the paramo of Cerro Tinuk is located
at a lower elevation (2458 m) with respect to most of the
other paramos of Costa Rica, which lie mostly above 3000
m in elevation. Climatic characteristics and vegetation of
this plateau have not been studied previously. We think
that the origin of the dwarf vegetation at the summit of
the hill is due to the inuence of the eastern trade winds
of the Caribbean, which pass the summit of Cerro Utyum
and collide frontally with the summit of Cerro Tinuk. e
location is exposed and very windy. e few isolated trees
are bent by the action of strong winds. Plants of P. tinukiana
are growing terrestrially, forming groups of several plants
among the coarse vegetation on the summit of the hill.
e population of P. tinukiana remains isolated from the
surrounding hills where no other plants of this species
were observed. No similar combination of particular
conditions, vegetation, elevation, and climate are found
on the surrounding mountain tops. Aside from plants
of P. tinukiana, no other species of the P. prismatocarpa
complex are known from this site. Populations of the
related P. brassavolae are common in the oak forest below
the summit of Cerro Tinuk, but they are absent in the
paramo at the top of the slope.
Phenology: Plants were observed in ower from May
to June.
Additional specimen examined: Puntarenas, Buenos
Aires, Buenos Aires, Olán, cumbre del Cerro Tinuk,
9°1729.1N, 83°1011.2W, 2412 m, bosque pluvial
premontano, terrestre en bosque de páramo, 25.06.2012,
A.P. Karremans 5550, D. Bogarín, E. Herrera, D. Jiménez &
V.H. Zúñiga (JBL).
4. Discussion
e species is similar to Prosthechea ionocentra (Rchb.f.)
W.E.Higgins; it diers mainly in the inorescence that
is developed from the penultimate mature pseudobulb
(rather than developed from the youngest pseudobulb).
Additionally, the purple spotted sepals and petals (rather
than immaculate); the cordate, acute lip (rather than
cordate-sagittate, acuminate) (Figures 3 and 4); the disc
with two long, narrow keels (shorter, thickened); the
stigmatic arms of the column, which are convergent,
rounded (rather than parallel, acute); and the narrow
BOGARÍN and KARREMANS / Turk J Bot
6
stigma (rather than wider) suggest that this is a
completely dierent species (Figure 5; Table). It shares
the “tardiorous” condition of the inorescence with P.
brassavolae and P. tardiora Mora-Ret. ex Pupulin. From
P. brassavolae the new species can be distinguished by the
presence of two lateral lobes of the lip (rather than without
the basal lobules) and the spotted sepals and petals (rather
than immaculate) (Figure 3). From P. tardiora it is readily
distinguished by the elongate rhizome and the cordate lip
of more than 3 cm long (rather than the short, congested
rhizome and the obovate-subpandurate lip of less than 2
cm long) (Figure 4; Table). e other related species, P.
prismatocarpa and P. neglecta Pupulin, have a similar oral
architecture, but they dier in the smaller owers with
tepals less than 2 cm long (vs. more than 3.5 cm long);
the triangular, narrower midlobe of the lip to 0.9 cm (vs.
cordate, wider to 1.2 cm); the sepals and petals mostly
stained with purple blotches (vs. sparsely purple freckles)
(Figure 3); and the shorter column, 0.9–1.0 cm long (vs.
1.4 cm long) (Figure 5; Table).
e following key of the P. prismatocarpa group was
modied from Pupulin (2002) to include the species
described herein:
Key to the species of the Prosthechea prismatocarpa
group (= Panarica)
1. Lip entire, without basal lobules
2. Pseudobulbs elongate, pyriform to lanceolate, lip
lanceolate-ovate, subcordate ………..….. P. brassavolae
2. Pseudobulbs shortened, ovoid, lip triangular and
basally truncate……................…………...…..P. mulasii
1. Lip 3-lobed, with 2 small lobules at the base
3. Sepals and petals immaculate……............P. ionocentra
3. Sepals and petals spotted or blotched
4. Inorescence developed from the pseudobulb of the
previous year
5. Rhizome elongated, lip >3 cm long; midlobe cordate…
……….............................................………...P. tinukiana
5. Rhizome short, lip <2 cm long; midlobe obovate-
subpandurate…..................................……...P. tardiora
4. Inorescence developed from the new pseudobulb
6. Sepals adaxially papillate; ovary swollen; inorescence
lax……...............................................…...……P. neglecta
6. Sepals adaxially glabrous; ovary clavate; inorescence
dense…...............................................…P. prismatocarpa
Tab le. Comparison among the species of the P. prismatocarpa complex.
Character P. brassavolae P. ionocentra P. mulasii P. neglecta P. prismatocar pa P. tardiora P. tinukiana
Internode rhizome
length (mm) 20–45 20–40 20 to 50 20–40 < 20 40
Pseudobulb shape Ovoid to pyriform Ovoid to pyriform Ovoid Narrowly ovo id Pyriform to
narrowly ovoid
Ovoid to
lanceolate-pyriform Ovoid to pyriform
Leaf length (cm) 15–26 10–20 14.0–25.5 26–32 13–32 19–35 18.8–20.0
Leaf width (cm) 3.0–4.5 2.6–5.0 14.0–25.5 1.8–4.6 2.5–5.2 3.6–5.0 5.0–6.2
Inorescence
Developed from
the new mature
pseudobulb
Developed from
the new mature
pseudobulb
Developed from
the previous mature
pseudobulb
Developed from
the new mature
pseudobulb
Developed from
the new mature
pseudobulb
Developed from the
previous mature
pseudobulb
Developed from the
previous mature
pseudobulb
Inorescence
length (cm) 13–40 25–35 to 28 To 33 15–45 26–35 To 17
Sepal length (mm) 35–55 35–41 27–37 19 25–31 18–23 36–38
Color of sepals
and petals Immaculate Immaculate Immaculate Blotched or
maculated
Blotched or
maculated
Blotched or
maculated
Freckled or
spotted
Labellum shape Unlobed 3-lobed Unlobed 3-lobed 3-lobed 3-lobed 3-lobed
Labellum length (mm) 25–30 26–33 40–61 15 20–25 16–19 32
Column length (mm) 15 13 13–15 9–10 9–10 9–10.0 14
Blooming season January–August May–August August (mainly) March–June April–August January–March May–June
Elevation (m a.s.l.) 1100–2700 900–1600 1850 1900–2800 1500–2400 200–600 2400
Distribution Mexico–western
Panama
Costa Rica–
Panama Mexico C osta Rica Costa Rica–
western Panama Costa Rica Costa Rica
BOGARÍN and KARREMANS / Turk J Bot
7
Acknowledgments
We are very grateful to Franco Pupulin, Eric Hágsater, and
Carlos Leopardi, who made valuable suggestions to this
manuscript. Victor Hugo Zúñiga and Erick Herrera were
kind enough to lead the expedition to the Tinuk and Daniel
Jiménez helped with eld logistics and accompanied the
trip. Many thanks to Lizbeth Oses for kindly inking the
illustration. We are thankful to the Costa Rican Ministry
of Environment and Energy (MINAE) and its National
System of Conservation Areas (SINAC) for issuing the
Scientic Passports under which wild specimens treated
in this study were collected. We are in debt to the Vice-
Presidency of Research of the University of Costa Rica
for providing support through the project “Filogenia
molecular de las especies de Orchidaceae endémicas de
Costa Rica” (814-B1-239).
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