Myoxanthus congestus (A.Rich. & Galeotti) Soto Arenas (2008

Rojas-Alvarado, Gustavo, Blanco, Mario A. & Karremans, Adam P., 2021, A taxonomic synopsis and morphological characterization of Myoxanthus (Orchidaceae: Pleurothallidinae), Phytotaxa 507 (3), pp. 211-258 : 233-235

publication ID	https://doi.org/ 10.11646/phytotaxa.507.3.1
persistent identifier	https://treatment.plazi.org/id/0E3EF64D-FFB1-850C-FF26-F92EFE2EFDF4
treatment provided by	Marcus
scientific name	Myoxanthus congestus (A.Rich. & Galeotti) Soto Arenas (2008
status

Treatment

11. Myoxanthus congestus (A.Rich. & Galeotti) Soto Arenas (2008 View in CoL : XXII) (Fig. 14A,B)

Basionym: Pleurothallis congesta Richard & Galeotti (1845: 17) View in CoL .

TYPE:— MEXICO. Linden s.n. [W-0079486!, drawing annotated by Richard and plant and flower fragment “Flor. in hort. bot. Fac. Med. Par. Octubre 1842 ”, lectotype designated by Soto Arenas 2008: t. 1053; isolectotype, W-0079482!] .

Heterotypic synonyms: Pleurothallis octomeriae Schlechter (1922: 21) . Myoxanthus octomeriae (Schltr.) Luer (1982a: 47) .

TYPE:— PANAMA. Chiriquí: An Baumen in Schluchten, c. 5000, Powell 252 [holotype: B, destroyed; lectotype, AMES-23789!, selected by Christenson (1991: 130); isolectotype MO-950657!] .

Pleurothallis ramentacea Garay & Dunsterville (1976: 364‒365) View in CoL .

TYPE:— VENEZUELA. Without precise locality, Steyermark s.n. (holotype: AMES-spirit, illustration!) .

Distribution: — Mexico, Guatemala, Belize, Honduras, Nicaragua, Costa Rica, Panama, Venezuela and Colombia.

Notes:— This species is morphologically similar to M. cereus , M. octomerioides and M. pulvinatus . From M. cereus , M. congestus is distinguished by the narrow elliptic leaves vs. broad elliptic to ovate, ovate petals vs. oblong, scarcely adaxially verrucose lip with angled margins vs. oblong and conspicuously verrucose. From M. octomerioides , it is distinguished by the yellowish whitish perianth vs. perianth suffused with pink to purple. From M. pulvinatus and M. congestus , it differs in the column with aciculate teeth on each side and acute to obtuse lip vs. triangular, frequently bidentate on each side and generally apiculate lip.

When Soto Arenas revised Mexican Myoxanthus , he noted that the original material of P. congesta fitted the concept of M. octomeriae better than that of M. octomerioides as previously stated by Luer (1982 a, 1992; see Rojas- Alvarado & Karremans 2020 for an extended discussion). Pleurothallis ramentacea , described from Venezuela by Garay & Dunsterville (1976), also fits the concept of P. congesta . See Incertae sedis at the end of this list of Myoxanthus species for a commentary of Pleurothallis elongata Klotzsch , which Rojas-Alvarado and Karremans (2020) included as a synonym of M. congestus .