doi: 10.1111/njb.02271 00 1–5

NORDIC JOURNAL OF BOTANY Research oliviae sp. nov. (, ) from Peru

Marta Kolanowska and Dariusz L. Szlachetko

M. Kolanowska (https://orcid.org/0000-0001-5347-5403) ✉ ([email protected]), Dept of Geobotany and Ecology, Faculty of Biology and Environmental Protection, Univ. of Lodz, Lodz, Poland and Dept of Biodiversity Research, Global Change Research Inst. AS CR, Brno, Czech Republic. – D. L. Szlachetko, Dept of Plant and Nature Conservation, Faculty of Biology, Univ. of Gdańsk, Gdańsk, Poland.

Nordic Journal of Botany A new of the orchid Myoxanthus, M. oliviae, is described based on 2019: e02271 Peruvian material. The novelty resembles M. serripetalus from which it differs by the doi: 10.1111/njb.02271 7–8-veined lateral sepals (versus 6- or 9-veined), the petals contracted below the apex and expanded again into a sagittate apex (versus apex caudate) and entire lip middle Subject Editor: Jasmyn Lynch lobe (versus fimbriate). The flowers M.of oliviae are pale brownish-purple, inter- Editor-in-Chief: Torbjörn Tyler nally intensively suffused with yellow, dark-purple spotted. The new species grows Accepted 2 August 2019 among rocks at the elevation of 2700–3100 m a.s.l. A key to Peruvian Myoxanthus representatives is provided.

Keywords: biodiversity, Neotropics, Pleurothallidinae

Introduction

The Neotropical genusMyoxanthus was described by Poeppig and Endlicher based on an epiphytic plant collected in Peruvian forest (Poeppig and Endlicher 1835). The authors considered this orchid similar to Specklinia Lindl., but with connate sepals. Myoxanthus was not recognized by taxonomists for almost 150 years until the re-evaluation by Luer (1982) in which the author transferred 36 species previously included in R. Br. and Humboldtia Ruiz and Pav. and described one new species – M. xiphion Luer. In addition, Luer (1983) discovered three new species (M. priapus Luer, M. gorgon Luer and M. affinoides Luer). In the first volume of Icones Pleurothallidinarum, Luer (1986) proposed additional transfer of eight species to Myoxanthus. Luer (1992) presented a complete revision of the genus proposing the first subgeneric division of Myoxanthus which was divided by the author into three subgenera named Myoxanthus, Satyria Luer and Silenia Luer. The morphological differences between these taxa refer to the ramicaul sheaths (scurfy or not) as well as inflorescence posi- tion (low on ramicaul, near ramicaul apex or at the leaf base). The nominal subgenus was further divided into three sections (nominal one, Antenella Luer and Scandentia Luer) based on plant’s habit (scandent, caespitose, repent, ramicauls proliferating

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1 or not). Additionally, in Luer’s revision of Myoxanthus the free or lateral sepals variously connate. The petals are fleshy, author proposed two transfers and described five new spe- often thickened in the apical part. The fleshy, rigid lip is cies within the genus. A decade later species not included often three-lobed and delicately hinged to the column foot. in the nominal subgenus were transferred to the newly cre- Two pollinia are produced. ated genus Pridgeon and M.W. Chase (Pridgeon The geographical range of Myoxanthus extends from south- and Chase 2002). Since 1992 ten new species have been ern Mexico and Belize to Bolivia and Brazil. So far, 18 species discovered, however, two of these (M. vittatus Pupulin and have been reported from Peru (Brako and Zarucchi 1993), M.A. Blanco and M. tomentosus (Luer) Pupulin and M.A. however, M. aspasicensis (Rchb. f.) Luer was meanwhile Blanco) were later transferred to Echinosepala Pridgeon and transferred to Echinosepala (Carnevali et al. 2008). Among M.W. Chase. national genus representatives, five species belong to the As currently recognized representatives of Myoxanthus are nominal section, four to Scandentia and eight to Antennella. epiphytic, rarely lithophytic or terrestrial which pro- A recent revision of herbarium material revealed an duce a single, erect, coriaceous leaf. The ramicauls are covered additional species in Peru which was usually misidenti- with scurfy sheaths. The inflorescence arise near the apex of fied as M. serripetalus (Kraenzl.) Luer (originally described the ramicaul and it consists of a single flower or fascicle of as Pleurothallis serripetala Kraenzl). The type specimen of single flowers. The dorsal sepal and lateral sepals can either be this taxon was collected by Weberbauer in the Peruvian

Figure 1. Myoxanthus oliviae sp. nov. (A) Habit. Scale bar = 5 cm (Plowman and Davis 4740, AMES), (B) dorsal sepal, (C) petal, (D) lateral sepal, (E) lip, (F) gynostemium, side view. Scale bars = 5 mm. Drawn from the holotype by N. Olędrzyńska.

2 VALLE and W were examined according to standard procedures. Each studied sheet was photographed and data from the labels were taken. Both vegetative and generative characters of each plant were examined. The perianth seg- ments and the gynostemium morphology were studied after softening flowers in boiling water. The examined specimens were compared with type material, diagnoses and original illustrations of Myoxanthus representatives.

Myoxanthus oliviae Kolan. & Szlach., sp. nov. (Fig. 1–3)

Aspecies similar to M. serripetalus but distinguished by having pale brownish-purple flowers which are internally intensively suffused with yellow and dark-purple spotted, 7–8-veined lateral sepals (versus 6- or 9-veined), petals Figure 2. Petals form variation of Myoxanthus oliviae sp. nov. contracted below apex, expanded again into sagittate apex (A) Vargas 20860, (B) Plowman and Davis 4740, (C) Núñez and (versus apex caudate) and entire lip middle lobe (versus Bengoa 8679. Drawn by N. Ol drzy ska. ę ń fimbriate). province of Junín, but unfortunately the original gathering Holotype: Peru, Cuzco, Prov. Urubamba, 3100 m a.s.l., was destroyed the in Berlin herbarium during World War II 5 December 1968, C. Vargas C. 20860 (AMES 113563!). and currently only a photograph of the holotype is available in the Field Museum of Natural History, Chicago. According Etymology to Luer (1992), M. serripetalus is perhaps ‘the easiest spe- In reference to Olivia Business Centre for supporting orchid cies of the genus to identify’ based on its fleshy flower with conservation initiative in Sibundoy valley, Colombia. verrucose and fringed lip and claw-like petals tips. However, during our studies we found specimens preliminary assigned Description to M. serripetalus but characterized by a completely different Epiphyte or lithophyte, large, caespitose plant. Ramicaul shape of petals apices and with entire lip middle margins. erect, stout, 24–48 cm long, enclosed by five tubular, his- We do believe that these plants represent a new species of pidulous sheaths. Leaf erect, coriaceous, 14–20 cm long, Myoxanthus. The new entity is described and illustrated here 3.0–3.5 cm wide, oblong-ovate, at apex rounded and retuse, and placed within a key to Peruvian species of Myoxanthus. cuneate at the subpetiolate base. Inflorescence a fascicle of single flowers arising at the apex of the ramicaul and open- ing successively; peduncles up to 10 mm long. Floral bracts Material and methods cymbiform, 7–9 mm long. Pedicel about 5 mm long. Ovary about 5 mm long, glandular-pubescent. Flowers reddish to Herbarium specimens of Myoxanthus deposited in AAU, pale brownish-purple, internally intensively suffused with AMES, BM, COL, JAUM, K, MO, RENZ, RPSC, UGDA, yellow and dark-purple spotted. Dorsal sepal 17–22 mm

Figure 3. Flowers of Myoxanthus oliviae sp. nov. (A–B; photo of BGH O-124228 by Senghas) and M. serripetalus (photo by Jenny, P-46/91). Photos obtained from the database of Swiss Orchid Foundation at the Herbarium Jany Renz and the Botanical Inst. of the Univ. of Basel.

3 Figure 5. Comparison of lip form of M. oliviae (A) and M. serripeta- lus (B). Scale bars = 4 mm. Drawn by N. Olędrzyńska from Núñez V. and Bengoa 8670 (A) and Hutchison and Wright 4074 (B).

lateral lobes; three-lobed, shortly, but broadly clawed; middle lobe 4.6–5.0 mm long, 2.2 mm wide, oblong- ovate, obtuse; lateral lobes 3.0–3.5 mm long, semicircular when expanded, with fimbriate margin; disc with a pair of lamellae and a vein running between them, deeply concave between lamellae. Gynostemium 9–10 mm long; column foot 4.3–4.5 mm long.

Distribution and habitat This species seems to be endemic to the Peruvian province of Urubamba where it has been found growing among rocks at the elevation of 2700–3100 m a.s.l.

Similar species The new species belongs to the sectionAntennella characterized by a very shortly repent or caespitose habit and an inflorescence consisting of successively produced flowers. The novelty is easily distinguished from all other repre- sentatives of Myoxanthus based on the shape of petals which are apically contracted and expanded again into a sagittate apex. While in several species the petals are also contracted above the middle and then widened again (e.g. in M. cimex, Figure 4. Myoxanthus serripetalus – dissected perianth. (A) Dorsal M. mejiae, M. reymondii), the apical part is more or less ovate, sepal, (B) petal, (C) lateral sepals, (D) lip. Scale bars = 5 mm. Drawn never sagittate. The new entity resembles M. serripetalus by N. Olędrzyńska from Vargas C. 3196 (AMES). (Fig. 3–5) from which it can be distinguished based on sev- eral characters according to material examined by the authors. long, 7–8 mm wide, ovate-lanceolate, subobtuse at apex, Except from petals form, M. oliviae differs from M. serripetalus concave in the centre, 5- or 7-veined. Lateral sepals con- in the venation of the lateral sepals (7–8-veined versus nate in the basal 1/3–1/2, 16–25 mm long, deeply concave 6- or 9-veined) and the entire middle lobe of the lip (versus at the base, free part 7.0–8.4 mm wide, obliquely ovate, lip middle lobe fimbriate). Flowers ofM. oliviae are pale sigmoid and subobtuse at the apex, 7–8-veined. Petals brownish-purple, internally intensively suffused with yellow, 7.5–10.5 mm long, 3.5–3.8 mm wide, subfalcate, oblong- and dark-purple spotted while M. serripetalus has very dark obovate in the basal 4/5 and their margin microscopically brownish-purple, suffused with yellow only in the centre, and serrate above basal 1/3, then contracted and expanded spotted dark-purple. Myoxanthus serripetalus was described again into a sagittate apical part with rounded apices, based on plants collected in Junín, Peru. Ecuadorian localities three-veined. Lip 7–8 mm long, 4.5–5.0 mm wide across (Pastaza) of this species were provided by Luer (1992).

4 Considering Peruvian material we confirmed the occurrence 11. Petals clavate at the apex ……………………………… of M. serripetalus also in the collections from the departments ………………………… M. reymondii (H. Karst.) Luer of Amazonas (Hutchison and Wright 4074, AMES 104443!) – Petals not clavate at the apex .……………………. 12 and Cuzco (Vargas C. 3196, AMES 65379!). 12. Petals apical part sagittate ………………….. M. oliviae – Petals apical part oblong to linear ………………… 13 13. Sepals over 25 mm long ……………………………… Additional specimens examined (Paratypes) .……………………….. M. serripetalus (Kraenzl.) Luer Peru, Cuzco, Prov. Urubamba, a 67 km de Cusco, desde el – Sepals up to 20 mm long ………………………… 14 Rio Calicanto hacia Chacchapata, Muris y sus alrededores. 14. Sepals glabrous or almost glabrous externally ……… 15 13°16′00″S 72°16′W, 2700–3020 m, 21 November 1987, – Sepals externally pubescent ……………………… 16 P. Núñez V. and E. Bengoa 8670 (AAU! ex MO), Prov. 15. Lateral sepals almost completely connate; petal apices Urubamba, Ollantaytambo, rocky hillsides above town, thickened; lip margins fimbriate ……………………… 9200 ft., 17 January 1975, T. Plowman and K. W. Davis ………… M. hirsuticaulis (Ames & C. Schweinf.) Luer 4740 (AMES!). – Lateral sepals connate in the basal third; petal apices thin, caudate; lip margins irregularly denticulate …………………………… M. antennifer Luer & Hirtz Key to Peruvian Myoxanthus species (adapted from Luer 1992) 16. Margins of lip middle lobe entire …………………. 17 – Margins of lip middle lobe minutely erose ………… 1. Habit scandent, ramicauls proliferating ……………… 2 ………………… M. simplicicaulis (C. Schweinf.) Luer – Habit caespitose or repent, ramicauls not proliferating 17. Lip lobed near the middle, at base with prominent ……………………………………………………… 5 elevated callus; gynostemium longitudinally winged but 2. Floral bract enclosing the base of the perianth ……… 3 without appendages ………………… M. priapus Luer – Floral bract not enclosing the base of the perianth – Lip lobed near the ecallose base; gynostemium with ……………………………………………………… 4 broad wings and a pair of digitate appendages ……… 3. Petals not surpassing sepals, margins entire, sepals ………………………… M. ceratothallis (Rchb. f.) Luer glabrous ……………………… M. frutex (Schltr.) Luer – Petals surpassing sepals in length, the upper margin Acknowledgements – We are grateful to the Swiss Orchid Foundation of petals in the lower quarter minutely erose; sepals and the Botanical Inst. of the Univ. of Basel for permission to use minutely ciliate outside ……………………………… photos from their database. Curators of AMES and AAU herbaria ……………………. M. gyas (Luer & R. Vásquez) Luer are thanked for Myoxanthus specimens available for loan. We would 4. Petals long ciliate-fimbriate; sepals lanceolate-triangular, like to thank Natalia Olędrzyńska for preparing line drawings. acuminate .………………. M. fimbriatus Luer & Hirtz Conflict of interest – The authors declare they have no conflict of – Petals glabrous, sepals more or less elliptic, obtuse at interest. apex ………………………… M. scandens (Ames) Luer 5. Flowers produced simultaneously …………………… 6 – Flowers produced successively …………………… 10 References 6. Floral bract enclosing the base of the sepals ………… ………………………. M. monophyllus Poepp. & Endl. Brako, L. and Zarucchi, J. L. 1993. Catalogue of the flowering – Floral bract not enclosing the base of the sepals ……. 7 plants and gymnosperms of Peru. – Miss. Bot. Gard. Press. Carnevali, G. et al. 2008. Orchidaceae. – In: Hokche, O. et al. 7. Petals oblong-ligulate ……… M. neillii Luer & Dodson (eds), Nuevo catálogo de la flora vascular de Venezuela. – Petals elliptic, ovate to oblong, but prominently Fundación Instituto Botánico de Venezuela Dr. Tobías Lasser, attenuating above the middle ………………………… 8 pp. 753–789. 8. Sepals and petals striped, lip apex cuspidate ………… Luer, C. A. 1982. A re-evaluation of the genus Myoxanthus. ………………………………. M. speciosus (Luer) Luer – Selbyana 7: 34–54. – Sepals and petals not striped, lip apex not cuspidate Luer, C. A. 1983. Miscellaneous new species in the Pleurothallidinae. ……………………………………………………… 9 – Phytologia 54: 379–390. 9. Sepals ca 3 times longer than wide; lip with rounded Luer, C. A. 1986. Icones Pleurothallidinarum Vol. 1. Systematics apex; gynostemium with a pair of teeth, …………… of the subtribe Pleurothallidinae. – Monogr. Syst. Bot. Miss. ……………………………….. M. affinis (Lindl.) Luer Bot. Gard. 15: 1–81. Luer, C. A. 1992. Icones Pleurothallidinarum IX. Systematic of – Sepals ca 8–10 times longer than wide; lip with Myoxanthus. – Monogr. Syst. Bot. Miss. Bot. Gard. 44: 1–111. truncate apex; gynostemium without a pair of teeth, Poeppig, E. F. and Endlicher, S. L. 1835. Nova Genera AC Species …………………………… M. exasperatus (Lindl.) Luer Plantarum quas in Regno Chilensi Peruviano et in Terra 10. Habit long-repent, ramicauls distanced for at least 1 cm Amazonica, Annis 1827 ad 1832. – Hofmeister. .………………………. M. trachychlamys (Schltr.) Luer Pridgeon, A. M. and Chase, M. W. 2002. Nomenclatural notes on – Habit very short repent or caespitose ……………. 11 Pleurothallidinae. – Lindleyana 17: 98–101.

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