A new species of Heteranthocidium (Orchidaceae) from Ecuador

DOI: 10.12905/0380.phyton59-2019-0043 Published online 10 Oct 2019 A new species of Heteranthocidium (Orchidaceae) from Ecuador Marta Kolanowska 1,2, Sławomir Nowak 3 & Dariusz L. Szlachetko 3 with 3 figures and 1 table Key words: Heteranthocidium, Heteranthocidium universitas-lodziensis, Orchidaceae. New species, taxonomy. Flora of Ecuador, Neotropics. Summary Kolanowska M., Nowak S. & Szlachetko D. L. 2019. A new species of Heteranthocidium (Orchidaceae) from Ecuador. Phyton (Horn, Austria) 59 (1 2): 43 48, with 3 figures and 1 table.* Heteranthocidium universitas-lodziensis, a new orchid species from Ecuador is described and illustrated. Morphologically, the novelty resembles H. echinops and H. hirtzii but differs from these taxa by having unequal tepals with petals being longer than the dorsal sepal, apically retuse petals, lip being broader than long and ornamented with a panduratesubrectangular pad densely covered with long ciliae and four somewhat elevated ridges. A key to the identification of Ecuadorian Heteranthocidium species is provided. 1. Introduction The Republic of Ecuador is sometimes referred to as the country of orchids (el país de las orquídeas). From the relatively small territory of 283,560 km² over 3000 Orchidaceae species were reported and new discoveries are still described (e.g. Dalström 2016, 2017, Thoerle & Cornejo 2016, Doucette & al. 2017, Carrera & al. 2018). Noticeably, over 1700 of them are national endemics and 9 % of these rare orchids belong to the Oncidiinae (Endara & al. 2009). While the general flower structure is similar in most Oncidium s.str., plants of just one group are characterized by the presence of dimorphic flowers. While fertile flowers resemble those observed in other oncidiums, sterile flowers are stellate, with 5 or 6 linear to lanceolate or oblanceolate segments. Lindley 1855 classified species with two morphological types of flowers in his section Plurituberculata-hymenoptera-heterantha. Kraenzlin 1922 included them in the newly created section Heterantha which was later elevated to the generic rank and named Heteranthocidium Szlachetko, Mytnik & Romowicz (Szlachetko & al. 2006). The revised specific composition of this taxon, in accordance with results of previous phylogenetic studies (Neubig & al. 2012) was presented by Szlachetko & Kolanowska 2015. In 2015, eleven new species of Heteranthocidium from Colombia and Suriname were described (Szlachetko & Kolanowska 2015, Szlachetko & al. 2015). As currently recognized, the genus includes 39 species distributed from Costa Rica to Brazil. Most of them grow as epiphytes in premontane and montane regions, however, H. pentadactylon occurs at higher altitudes of about 3500 m (Senghas 1997). Pseudobulbs of Heteranthocidium are ellipsoid to ovoid, flattened, apically uni- or bi-foliate. The lateral inflorescence is paniculate and many-flowered. Their lip is sessile or shortclawed, entire to 3-lobed, with a prominent callus which is usually complex, fleshy, consisting of basal projections, ridges and digitate appendages, often with knob-like projections on the sides. The gynostemium is rather massive, distinctly swollen above the narrow and somewhat sigmoid base, and the column part is broadly winged near the stigma. So far 13 species of Heteranthocidium were found in Ecuador: H. abortivum (Rchb.f.) Szlach., Mytnik & Romowicz H. acinaceum (Rchb.f.) Szlach., Mytnik & Romowicz H. calanthum (Rchb.f.) Szlach., Mytnik & Romowicz H. cultratum (Lindl.) Szlach. & Kolan. H. echinops (Königer) Szlach. & Kolan. 1 ) Department of Biodiversity Research, Global Change Research Institute AS CR, Bělidla 4a, 603 00 Brno, Czech Republic 2 ) Department of Geobotany and Plant Ecology, Faculty of Biology and Environmental Protection, University of Lodz, Banacha 12/16, 90-237 Lodz, Poland; corresponding author (e-mail: marta.a.kolanowska@gmail.com) 3 ) Department of Plant Taxonomy and Nature Conservation, Faculty of Biology, University of Gdańsk, Wita Stwosza 59, 80-308 Gdańsk, Poland *) Printed volume published ## ### #### Kolanowska & al. 43

H. heteranthum (Poepp. & Endl.) Szlach., Mytnik & Romowicz H. heterodactylum (Kraenzl.) Szlach. & Kolan. H. hirtzii (Dodson) Szlach. & Kolan. H. millei (Schltr.) Szlach. & Kolan. H. orthotis (Rchb.f.) Szlach., Mytnik & Romowicz H. pentadactylon (Lindl.) Szlach., Mytnik & Romowicz H. retusum (Lindl.) Szlach. & Kolan. H. semele (Linden ex Rchb.f.) Szlach. & Kolan. Recent studies on Oncidiinae conducted in several local herbaria revealed the existence of a distinctive species which is here described as new. 2. Material and methods In the course of our studies on the genus Heteranthocidium a total of over 1400 herbarium specimens and liquid preserved flowers of oncidioid orchids deposited in AMES, AMO, BM, COL, CUVC, F, FLAS, HA, HUA, JAUM, K, LOJA, LPB, MO, NY, Fig. 1. Heteranthocidium universitas-lodziensis. (A) Habit. (B) Inflorescence fragment. (C) Flower, side view. (D) Flower, front view. (E) Dorsal sepal. (F) Petal. (G) Lateral sepal. (H) Lip. (I) Gynostemium. (J) Sterile flower element. Drawn by S. Nowak from the type material. 44 Phyton 59 (1 2)

QCA, QCNE, P, PMA, UGDA, UTPL, VALLE and W were examined according to the standard procedures. Both vegetative (pseudobulbs, leaves) and floral characters of each plant were examined and the measurements were taken. The morphology of flowers was studied after boiling, using a stereomicroscope. Acronyms for herbaria follow Index Herbariorum (Thiers 2018+). The CorelDraw v.12 software was used to prepare the distribution map. 3. Taxonomy Heteranthocidium universitas-lodziensis Kolan., S. Nowak & Szlach., spec. nova (Figs. 1, 2) Holotypus: Ecuador: Morona-Santiago. Domono. 2 12 00 S 78 5 00 W, 1350 m, 18 November 1995, L. Suin 17, HA! Isotypus: HA! Diagnosis: Species distinguished from Heteranthocidium echinops (Königer) Szlach. & Kolan. and H. hirtzii (Dodson) Szlach. & Kolan. by the fertile flowers with petals being longer than the dorsal sepal but subequal to the lateral sepals, the petals Fig. 2. Heteranthocidium universitas-lodziensis. Lip ornamentation close-up. being retuse at the apex, the lip being broader than long and ornamented with a pandurate-subrectangular pad densely covered with long ciliae and 4 somewhat elevated ridges. From H. hirtzii the new species also differs in having a ciliate gynostemium base, and from H. echinops by lacking a crisped and erose lip margin, and by the apical lobules constituting c. 1/3 of the total lip length. Eponymy: Named in reference to the University of Lodz. Description: Pseudobulbs 7 11 cm long, fusiform, compressed, bifoliate. Leaves short-petiolate, 10 17 cm long, 2.5 3 cm wide, oblong-lanceolate to oblong-oblanceolate, acute. Inflorescence lateral, c. 70 cm long, paniculate, slightly fractiflex, laxly many-flowered, branches c. 4.5 cm long, usually with a single, terminal, fertile flower and several sterile flowers below. Sterile flowers with obovate, acute, 1-veined segments 2.5 4 mm long, an ovary up to 1.3 mm long, and a floral bract up to 1.5 mm long. Fertile flowers yellow with transverse brown stripes in the central part of tepals and lip speckled with brown in the central part. Ovary together with pedicel 15 20 mm long, ovary slightly sigmoid. Floral bract 2 mm long, ovate, obtuse. Dorsal sepal 7.1 mm long, 2 mm wide, obovate above the claw, apex truncate with small apiculus, microscopically ciliate in the central and basal part, 3-veined. Lateral sepals short connate at the base, 8.2 mm long, 2.5 mm wide, obliquely obovate above the claw, apex acute, microscopically ciliate in the central and basal part, 3-veined. Petals 8 mm long, 3.1 mm wide, obliquely obovate above the short claw, retuse at the apex, microscopically ciliate in the central and basal part, primarily 3-veined, lateral veins branching. Lip 9.5 mm long, 11 mm wide, lamina transversely elliptic in outline, apical lobules constituting c. 1/3 of the lip length, diverging, obliquely ovate, rounded, slightly undulate; disc papillate in the central part, at the base with a thin pandurate-subrectangular, apically incised pad densely covered with long ciliae and 4 somewhat elevated ridges. Gynostemium 5 mm long including the two prominent wings, ciliate in the basal part. Taxonomic notes: The new species is distinguished from most other representatives of the genus by the lack of fleshy, digitate or knob-like calli at the lip base. Instead the lip is ornamented with a rather thin pad which is covered with long-ciliae. Only two Heteranthocidium species, H. hirtzii and H. echinops, have this kind of lip ornamentation. In the latter species, the tepals are equal in length (vs. unequal in the new entity), petals are rounded at the apices (vs. apex retuse), the lip margin is crisped and erose (vs. indistinctly and broadly crenate), the whole lip is equally long and wide (vs. wider than long), with apical lobules constituting almost 1/2 of Kolanowska & al. 45

Fig. 3. Distribution of Heteranthocidium universitas-lodziensis, H. echinops and H. hirtzii in Ecuador. the total lip length (vs. 1/3), and the lip is ornamented with a rectangular pad with 3 longitudinal furrows (vs. a pandurate-subrectangular pad densely covered with long ciliae and 4 somewhat elevated ridges). The gynostemium of H. hirtzii is glabrous unlike in the new species, its tepals are apically obtuse, and the lip callus has the form of an oval, pubescent pad. Moreover, in H. hirtzii the petals are longer than the sepals (10 vs. 7 mm) and the lip is longer than wide (15 12 mm). The comparative morphology of H. universitas-lodziensis, H. hirtzii and H. echinops is presented in Table 1. Distribution and ecology: This species is known exclusively from the eastern Andean slope in Ecuador (Fig. 3). It is growing at an altitude of about 1350 m and flowering in November. Conservation status: Due to insufficient field data and incomplete information about distribution of the new species it should be regarded as data deficient (DD), according to the IUCN Red List Categories (IUCN 2012). 4. Key to Ecuadorian Heteranthocidium species 1 Lip middle lobe entire, ovate to ovate-triangular... 2 1* Lip middle lobe more or less bilobulate or transversely reniform... 4 46 Phyton 59 (1 2)

Table 1. Comparative morphology of Heteranthocidium universitas-lodziensis, H. hirtzii and H. echinops. H. universitas-lodziensis H. hirtzii H. echinops Pseudobulbs 7 11 cm long, less than 1 cm wide up to 7 cm long, 1 cm wide up to 6 cm long, 1.5 cm wide Leaves 10 17 2.5 3 cm, oblong-lanceolate to oblong-oblanceolate, acute up to 13 1.5 cm, linearoblong to oblong-ovate up to 10 1.6 cm, lanceolate, acute Inflorescence c. 70 cm long, slightly fractiflex up to 55 cm long, slightly fractiflex 60 100 cm long, straight Dorsal sepal 7.1 2 mm, obovate above the claw, apex truncate with small apiculus up to 8 3 mm, spathulateobovate, obtuse 8 1.5 mm, cuneate spathulate, rounded, apiculate Lateral sepals 8.2 2.5 mm, obliquely obovate above the claw, acute 7 2 mm, obliquely ovate, obtuse 8 1.5 mm, obliquely cuneate spathulate, acuminate Petals 8 3.1 mm, obliquely obovate above short claw, apex retuse up to 10 8 mm, obovate, obtuse 8 3 mm, oblong-cuneate [spathulate], rounded, obtusely pointed Lip 9 11 mm, margins indistinctly, broadly crenate, apical lobules constituting c. 1/3 of the lip length, almost as wide as basal part of the lip up to 15 12 mm, margins erose, apical lobules constituting c. 1/3 of the lip length, narrower then basal part of the lip 10 10 mm, margins crisped, erose, apical lobules constituting almost 1/2 of the lip length, almost as wide as basal part of the lip Lip callus pandurate-subrectangular, apically incised pad densely covered with long ciliae and 4 somewhat elevated ridges oval, pubescent pad rectangular pad with 3 longitudinal furrows Gynostemium 5 mm long, ciliate near the base c. 6 mm, glabrous 5 mm long, pubescent below stigma Distribution Ecuador. Morona-Santiago. Domono. Alt. 1350 m. (Suin 17) Ecuador. Napo. Along road from Cutundo to Hollin to Loreto. Alt. 1000 m. (Hirtz & al. 3940) Ecuador. Morona-Santiago. Bei Juan Bosco. Alt. 1700 m. (Königer & al. K-338a) 2 Lip basal part cuneate... H. acinaceum 2* Lip basal part more or less transversely elliptic... 3 3 Inflorescence peduncle much shorter than rachis, branches numerous, each branch with 1( 2) fertile and 4 7 sterile flowers... H. abortivum 3* Inflorescence peduncle as long as or longer than rachis, branches 5 6, each branch with 1 fertile and 1 2 sterile flowers... H. orthotis 4 Lip callus in form of pubescent or long-ciliate pad... 5 4* Lip callus fleshy, glabrous, sometimes with inconspicuous pubescence at the base... 7 5 Inflorescence straight, all tepals equal in length, lip apical lobules constituting almost half of the total lip length...h. echinops 5* Inflorescence slightly fractiflex, tepals unequal in length, lip apical lobules constituting ca. 1/3 of the total lip length... 6 6 Lateral sepals and petals subequal in length, petals with retuse apex, lip broader than long (9 11 mm), with pandurate-subrectangular pad......h. universitas-lodziensis 6* Petals distinctly longer than lateral sepals, petals obtuse, lip longer than wide (15 12 mm), with oval, pubescent pad... H. hirtzii 7 Middle lip lobe narrower than basal lip part (across lateral lobes)... 8 7* Middle lip lobe broader or equally wide as basal lip part (across lateral lobes)... 9 8 Lip apex notched, callus in form of 3 ridges terminated in upcurved digitate projections, flanked by some additional projections on each side...h. heteranthum 8* Lip apex truncate, callus in form of 5 elevated keels, the 3 central keels with digitate, upcurved projections at the apex... H. semele 9 Callus pubescent or ciliate in the front...... H. cultratum 9* Callus glabrous...10 10 Gynostemium wings bilobed...11 Kolanowska & al. 47

10* Gynostemium wings unlobed...13 11 Upper lobe of gynostemium wings narrow, lanceolate... H. heterodactylum 11* Upper lobe of gynostemium wings broadly ovate...12 12 Sepals linear-lanceolate... H. pentadactylon 12* Sepals spathulate...h. retusum 13 Gynostemium wings subquadrate in outline...... H. millei 13* Gynostemium wings dolabriform in outline...... H. calanthum Acknowledgements We are grateful to Raffaella Ansaloni, the director of the Herbario Azuay, for access to the Orchidaceae collection in Cuenca. The research described here was supported by the MŠMT grant (LO1415) and the National Science Centre, Poland, PRELUDIUM (2016/21/N/NZ8/01601). References Carrera M., Baquero L. & Zak V. 2018. A new species of Pleurothallis (Orchidaceae: Pleurothallidinae) from Quito, Ecuador. Lankesteriana 18(2): 85 91. <http:// dx.doi.org/10.15517/lank.v18i2. 33398>. Dalström S. 2016. A new Oliveriana (Orchidaceae: Oncidiinae) from Ecuador. Lankesteriana 16(3): 345 348. <http://dx.doi.org/10.15517/lank.v16i3.27269>. Dalström S. 2017. A new large-flowered Cyrtochilum (Orchidaceae: Oncidiinae) from Ecuador, named in honor of two orchid research legends. Lankesteriana 17(2): 279 284. <http://dx.doi.org/10.15517/lank.v17i2.30202>. Doucette A., Portilla J., Medina H. & Cameron K. M. 2017. A new species of Pleurothallis (Orchidaceae: Pleurothallidinae) from Ecuador. Phytotaxa 295(2): 194 198. <http://dx.doi.org/10.11646/phytotaxa.295.2.7>. Endara L., Williams N. & León-Yánez S. 2009. Patrones de endemismo de orquídeas endémicas ecuatorianas: perspectivas y prioridades para la conservación. In: Pridgeon A. M. & Suarez J. P. (eds.), Proceedings of the Second Scientific Conference on Andean Orchids, p. 63 70. Universidad Técnica Particular de Loja, Loja, Ecuador,. IUCN 2012. IUCN Red List Categories and Criteria: Version 3.1. Second edition. IUCN; Gland, Switzerland and Cambridge, UK. iv + 32 pp. <https://portals.iucn. org/library/sites/library/files/documents/rl-2001-001-2nd.pdf> Kraenzlin F. 1922. Orchidaceae-Monandrae, Tribus Oncidiinae-Odontoglosseae Pars II. Engler A. (ed.), Das Pflanzenreich, vol. IV, 50: 1 344. Lindley J. 1855. Folia Orchidacea. Oncidium 37. J. Matthews, London. 59 pp. Neubig K. M., Whitten W. M., Williams N. H., Blanco M. A., Endara L., Burleigh J. G., Silveira K., Cushman J. C. & Chase M. W. 2012. Generic recircumscriptions of Oncidiinae (Orchidaceae: Cymbidieae) based on maximum likelihood analysis of combined DNA datasets. Botanical Journal of the Linnean Society 168: 117 146. <https://doi.org/10.1111/j.1095-8339.2011.01194.x>. Senghas K. 1997. Oncidiinae. Rudolf Schlechter s Die Orchideen, Band I/c: 33 36. Szlachetko D. L. & Kolanowska M. 2015. Reconsideration of Heteranthocidium (Oncidiinae, Orchidaceae): new species and taxonomic transfers. Plant Systematics and Evolution 301(7): 1793 1805. <https://doi.org/ 10.1007/s00606-014-1189-3>. Szlachetko D. L., Mytnik-Ejsmont J. & Romowicz A. 2006. Genera et species Orchidalium 14. Oncidieae. Polish Botanical Journal 51: 53 55. Szlachetko D. L., Olędrzyńska N. & Kolanowska M. 2015. Four new species of Heteranthocidium (Orchidaceae) from Colombia and Suriname. Polish Botanical Journal 60(2): 135 140. <https://doi.org/ 10.1515/pbj-2015-0027>. Thiers B. 2018+. Index Herbariorum: A global directory of public herbaria and associated staff. New York Botanical Garden s Virtual Herbarium, New York. <http:// sweetgum.nybg.org/science/ih/>. Thoerle L. & Cornejo X. 2016. Lepanthopsis kayi (Pleurothallidinae, Orchidaceae), a new species from eastern Ecuador. Harvard Papers in Botany 21(2): 247 250. <https://doi.org/10.3100/hpib.v21iss2.2016.n9>. (Received 3 Apr 2019, accepted 26 Aug 2019) 48 Phyton 59 (1 2)