Oberonia mucronata (D.Don) Ormerod & Seidenf.

Geiger, D. L., 2019, Studies on Oberonia 5 (Orchidaceae: Malaxideae). Twenty-four new synonyms, and a corrected spelling, Blumea 64 (2), pp. 123-139 : 131-132

Oberonia mucronata (D.Don) Ormerod & Seidenf. — Fig. 9

Oberonia mucronata (D.Don) Ormerod & Seidenf. (in Seidenfaden (1997) 20). Basionym. Stelis mucronata D. Don (1825) 32. — Type: Hamilton s.n. (questionable syn BM 000088238 1948b), Nepal.

Oberonia manipurensis Chowlu, Y.N.Devi,A.N.Rao, N.Angela, H.B.Sharma & Akimpou (2015) 42, f. 1–2. — Type: Chowlu 00362 (holo CAL); Chowlu 00441 (para/iso COGCEHR), India, Manipur, Tamenglong District , Tamenglong (N24°48.78' E93°32.77', 403 m a.s.l.), 7 June 2013, syn. nov.

Notes — Oberonia mucronata is used here in the currently accepted species concept (e.g., Ansari & Balakrishnan 1990, Averyanov 2013; Fig. 9a–d ). The original scale bar for Ansari & Balakrishan’s (1990) figure for the entire flower ( Fig. 9a ) is evidently wrong. Most likely it is a 2 mm scale bar, which agrees with the 2.5 mm dimension of the overall flower given in the description. This error has been corrected here for Fig. 9a–d . There are questions about the standing of the alleged type in BM. Misra (2004) indicated that the specimen in BM is not the type, because it is a fruiting specimen of O. ensiformis . Don (1825) described the flowers agreeing with the common species concept of O. mucronata (lip oval, acute, serrulate), and not of O. ensiformis with a quadrate, panduriform lip. The BM specimen has as number 1948b, which suggest a Wallich specimen. Wallich 1948 consists of Oberonia ‘ iridifolia (Roxb.) Lindl. ’ specimens, an illegitimate name (see http://wallich.rbge.info for details). Records of O. iridifolia often refer to what is currently labelled O. mucronata , but that name historically was used as a catch-all for several Oberonia species. In fact, Wallich 1948 consists of multiple species. Wallich 1948.1 is from Nepal and was collected in 1821, but there is no Wallich 1948b. Additionally, the collector specified by Don (1825) is Hamilton; for other species he cited Wallich, which demonstrates that Don (1825) distinguished between those two collectors. In conclusion, the BM specimen cannot be considered a type of Stelis mucronata , and the species concept of O. mucronata is not affected by the identity of the BM specimen.

The P database identifies ‘isotypes’of O. mucronata (P00404924, P00404925), with gathering number Wallich 1948b (see above). The gathering was collected in 1832 according to P database, after the description of Stelis mucronata in 1825. Accordingly, the P specimen has no standing as any type, and casts further doubts on the standing of the BM specimen. The detailed drawing of the flower on the sheet clearly shows O. mucronata . Oberonia manipurensis is here considered a synonym of O. mucronata . The flower ( Fig. 9e–f ) shows the reflexed petals and sepals, the lip has the characteristic deep serration along the triangular sides and the indentation at the tip of the epichile ( Fig. 9 ). The orange colour form is also known from elsewhere ( Fig. 9g –h ) while the more typical greenish form is shown in Fig. 9i . The dense irregular arrangement of the flowers on the inflorescence, and the habit also agrees with O. mucronata . Chowlu et al. (2015) compared their species with O. pachyphylla , which, however, has a much thicker rachis with almost embedded flowers, and O. multidentata , which has distinct lateral lobes with strong serrations and the habit consists of short leaves that are barely as long as wide. Chowlu et al. (2015) did not compare their new species to O. mucronata or any of its known synonyms.

The dimensions given by Chowlu et al. (2015) need to be taken with much caution, because the scale bars for the various portions of the plants are grossly incongruent. Scaling the a

b

scale bars to one or the other scale bar ( Fig. 9e–f ) show that there is an approximate 50 % difference between them. While the dimensions given in the protologue of O. manipurensis are smaller (1–1.2 mm) than for typical O. mucronata (2–2.5 mm), using the scale bar for the entire plant ( Fig. 1a ) reveals that the flowers are rather 2 mm in size. Given the structural identity and the demonstrable gross inaccuracies in the scale bars, the alleged size differences are here explained as a measurement error.

Chowlu et al. (2015) cited as type Chowlu 00362, 00441 as composite holotype and isotype: In correcting the type designations, Chowlu (2016) referred to Chowlu 00441 in the narrative as isotype, but the type section identified that second number as the paratype: The latter would be correct if the two numbers are considered two separate gatherings. Sennikov (2015) discussed this designation, and argued that the two Chowlu numbers are field numbers of a single gathering; the dual numbers suggesting two gatherings should not invalidate the description due to ICN Art. 8.3. If that view should prevail, then Chowlu 0441 is a duplicate of the holotype, therefore, an isotype: I consider the clerical error by Chowlu et al. (2015) insufficient to make O. manipurensis a nom. illeg., which does not affect its recognition as a synonym of O. mucronata .

Oberonia mucronata has multiple additional synonyms; see Seidenfaden (1997) for discussion.

Figures

Fig. 9 Oberonia mucronata. a–d. Representative illustration of O. mucronata from Ansari & Balakrishnan (1990: f. 15). a. Entire flower; b–d. variability of the lip. — e–f. Illustrations of the type of O. manipurensis. e. Entire flower; f. lip. — g–h. Orange form of O. mucronata. DLG452, HOAG53. g. SEM of single flower; h. Z-stacked micrograph from live plant, 175 frames. — i. Yellowish green form of O. mucronata. DLG631, HOAG204. Z-stacked micrograph from live plant, 23 frames. — Scale bars = 1 mm.

Fig. 1 a–b. Oberonia bicornis Lindl. drawing of Type: a. Reichenbach her- barium 9857; b. Oberonia tenuis drawing of type in Reichenbach herbarium 35460. Figure rotated 180˚ to show flowers in same orientation.