Murdannia semifoliata (C.B.Clarke) G. Brueckn ., Nat. Pflanzenfam. (ed. 2)15a: 173. 1930.

Pellegrini, Marco Octavio de Oliveira, Faden, Robert B. & Almeida, Rafael Felipe de, 2016, Taxonomic revision of Neotropical Murdannia Royle (Commelinaceae), PhytoKeys 74, pp. 35-78 : 60-61

7. Murdannia semifoliata (C.B.Clarke) G. Brueckn., Nat. Pflanzenfam. (ed. 2)15a: 173. 1930. Figs 8 , 10

Phaeneilema semifoliata (C.B.Clarke) G. Brückn., Notizbl. Bot. Gart. Berlin-Dahlem 10 (91): 56. 1927.

Aneilema semifoliatum C.B.Clarke, C.B.Clarke in Moore, Trans. Linn. Soc. London, Bot. 4: 498. 1895. Lectotype (designated here): BRAZIL. Mato Grosso: Santa Cruz [do Xingú], fl., Oct 1891-1892, S.M. Moore 541 (BM barcode BM000938202!; isolectotypes: B barcode B100367821!, NY barcode NY00247404!).

Description.

Herbs ca. 20.0-70.0 cm tall, perennial, rhizomatous with a definite base, terrestrial to paludal to rooted emergent in open flooded fields. Roots tuberous, thick and fusiform, medium to dark brown, densely to sparsely pilose with medium to dark brown hairs, emerging from the short rhizome and from the basal nodes. Rhizomes short, brown, buried in the sand or soil. Stems erect, succulent, unbranched; internodes 1.2-13.3 cm long, green to vinaceous, glabrous, with a line of hyaline, eglandular hairs opposite to the leaf above. Leaves spirally-alternate, evenly distributed along the stems, the distal ones much smaller than the basal ones (which are generally bladeless sheaths with lamina no longer than 1.8 cm); sheaths 0.5-2.3 cm long, green to vinaceous, glabrous, with a line of hyaline, eglandular hairs opposite to the leaf above, margins setose to ciliate; lamina 0.2-8.9 × 0.2-0.7 cm, succulent, canaliculate, slightly falcate, green on both sides, glaucous, drying olive-green on both sides, linear-triangular to triangular, glabrous, base truncate, margins light green, setose at the base, ciliate at the middle, glabrous at the apex, apex acuminate; midvein inconspicuous on both sides, rarely slightly obtuse abaxially, secondary veins inconspicuous. Inflorescences (1-)2-6, terminal and axillary from the uppermost nodes, fascicle-like, composed of 1-2-(3) verticillate cincinni; peduncles absent; basal bract inconspicuous; cincinni bracts 0.4-1.3 × 0.1-0.3 cm, tubular, amplexicaul; cincinni 1-flowered, erect, straight, peduncle 0.8-4.2 mm long, light green to pink to vinaceous, glabrous, internodes inconspicuous; bracteoles inconspicuous, generally caducous. Flowers bisexual or male, actinomorphic, ca. 0.6-2.3 cm diam.; floral buds ellipsoid, 4.9-7.2 × 1.7-2.2 mm, light green to pink; pedicels 1.4-1.1 mm long, light green to pink to vinaceous, glabrous, erect and elongate in fruit; sepals 4.8-8.0 × 1.8-3.3 mm, triangular to ovate-triangular, cucullate, pink to pinkish brown, glabrous, apex acute, margins hyaline pink to hyaline vinaceous; petals equal, 0.5-1.2 × 0.3-0.8 cm, obovate, slightly cucullate, lilac to purple or mauve, rarely white, medially bearded with moniliform hairs on the adaxial surface, hairs lilac to purple, base cuneate, margins entire, apex acute to obtuse; stamens 3, equal, filaments gently curved at the apex, 3.2-5.0 mm long, lilac to purple, densely bearded with moniliform, lilac to purple hairs, hairs slightly shorter than the filaments, anthers linear-oblong to oblong, 2.0-3.5 × 0.4-0.7 mm, connective purple, anthers sacs lilac to purple, pollen lilac; staminodes 3, equal, filaments straight, 3.1-4.3 mm long, pale lilac to lilac, densely bearded with moniliform, lilac to purple hairs, hairs slightly shorter than the filaments, antherodes hastate, 0.7-2.0 × 0.5-1.2 mm, connective golden yellow, lobes conspicuous, cream-colored to pale yellow; ovary ellipsoid to oblongoid, 1.5-3.3 × 0.5-1.0 mm, 3-locular, light green to green, smooth, glabrous, style gently curved at the apex, ca. 3.2-4.5 mm, lilac to purple, stigma capitate, lilac to purple. Capsules 5.8-1.2 × 3.3-5.6 mm, 3-locular, 3-valved; oblongoid to broadly oblongoid, apiculate due to persistent style, light brown when mature, smooth, glabrous. Seeds 6 per locule, 2.2-3.1 × 2.0-2.8 mm, cuboid to polygonal, slightly cleft towards the embryotega, testa dark brown to greyish brown, densely farinose, scrobiculate, with ridges radiating from the embryotega; embryotega semilateral, relatively inconspicuous, without a prominent apicule, generally covered by a cream farina; hilum linear, less than ½ the length of the seed, on a weak ridge.

Specimens seen.

BOLIVIA. Santa Cruz: San Ignacio de Velasco, Oct 1958, M. Cardenas 5629 (BOLV, US). BRAZIL. Mato Grosso: Bananalzinho, Nov 1914, J.G. Kuhlmann 89 (R, SP); Braco, rio Arinos, 26 Sep 1943, J.T. Baldwin Jr. 3097 (US); Cuiabá, entre Cuiabá e Goyaz, Nov-Dec 1844, M.A. Weddell 3018 (P); loc. cit., rodovia MT-364, 35 km S de Cuiabá, 13 Nov 1975, G. Hatschbach 37491 (K, MBM); Nova Olímpia, Chapada dos Guimarães, 10 Oct 1995, J.H.A. Dutilh 199 (UEC); Poconé, 50 km S of Poconé on Transpantaneira highway to Porto Jofre, 27 Oct 1985, W. Thomas et al. 4641 (INPA, NY, US); loc. cit., highway Poconé-Porto Cercado, ca. km 21, 17 Feb 1992, M. Schessl 100/1-10 (UFMT, US); loc. cit., about 21 km S of Poconé, 7 Oct 1992, M. Schessl 071092-1-1 (UFMT, US); loc. cit., fazenda Ronco Bugiu, ca. 6-8 km à esquerda da rodovia Transpantaneira Poconé-P. Jofre, km 36, 31 Oct 1992, A.L. Prado et al. 3218 (HURB, UEC, UFMT); loc. cit., 22 Nov 1992, A.L. Prado et al. 2736 (HURB, UEC, UFMT); Rosário Oeste, ca. 2 km de Marzagão em direção à Planalto da Serra, 7 Oct 1997, V.C. Souza et al. 20255 (ESA, UFMT, UEC); Santo Antônio de Leverger, Barão do Melaço, km 30 of Leverger highway, 5 Nov 1991, M. Schessl 2421 (CH, UFMT, US); Mato Grosso do Sul: Aquidauana, entre as fazendas São Salvador e Costa Rica, 19 Nov 1995, A. Pott et al. 7628 (CGMS, CPAP, US); loc. cit., rodovia Taunay, fazenda Santa Cruz, próximo da aldeia indígena Ipegue, 20 Nov 2002, G. Hatschbach et al. 74377 (MBM).

Distribution and habitat.

Murdannia semifoliata occurs mainly in Brazil (in the states of Mato Grosso and Mato Grosso do Sul) and in Bolivia (Fig. 10 ). It grows in open flooded grass fields in the Amazon, Cerrado and Chaco domains.

Phenology.

It was found in bloom and fruit from September to February.

Conservation status.

Murdannia semifoliata possesses a EOO of ca. 298,091.226 km2 and a AOO of ca. 22,500.000 km2. Despite the relatively great number of collections, most of them are in the state of Mato Grosso, with only one known collection on the state of Mato Grosso do Sul and another one from Bolivia. This whole region is under great treat due to the constant deforestation for cattle ranching. Thus, we believe that following the IUCN recommendations ( IUCN 2001), Murdannia semifoliata should be considered Nearly Threatened.

Nomenclatural notes.

When describing Aneilema semifoliatum , Clarke (1895) mentions "Crescit ad Santa Cruz, ubi mens. Oct. floret. (N. 541)". The specimen at BM matched the protologue perfectly. Furthermore, it possesses a detailed description and was identified by Clark himself. Thus, it is here designated as the lectotype of Aneilema semifoliatum .

Discussion.

Murdannia semifoliata , as aforementioned, is morphologically similar to Murdannia schomburgkiana . They share a peculiar vegetative morphology, inflorescence architecture, and petals medially bearded with moniliform hairs on the adaxial surface, not similar to any other Neotropical species. Murdannia semifoliata is especially distinctive due to its extremely reduced blades of the leaves bearing inflorescences, produced during the flowering period (Table 1 ). In most individuals, the blades are so reduced that the whole plant seems to be aphyllous. Furthermore, Murdannia semifoliata and Murdannia schomburgkiana are the only Neotropical species to possess more than two seeds per locule, which gives the seeds a peculiar cuboid to polygonal shape.

Figures

Figure 8. Murdannia semifoliata (C. B. Clarke) G. Brueckn. Lectotype of Aneilema semifoliatum (BM barcode BM 000938202). Photograph courtesy of The Natural History Museum of London.

Figure 10. Distribution map of Neotropical Murdannia Royle. Full circles Murdannia burchellii Full stars Murdannia engelsii Triangles Murdannia gardneri Stars Murdannia paraguayensis Full squares Murdannia schomburgkiana Squares Murdannia semifoliata.