Murdannia gardneri (Seub.) 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 : 48-50

3. Murdannia gardneri (Seub.) G. Brueckn., Nat. Pflanzenfam. (ed. 2)15a: 173. 1930. Figs 3 , 4 , 10

Phaeneilema gardneri (Seub.) G. Brückn., Notizbl. Bot. Gart. Berlin-Dahlem 10 (91): 56. 1927.

Aneilema gardneri Seub., in Martius, Fl. Bras. 3 (1): 259. 1855. Lectotype (designated here): BRAZIL. Goyaz, moist places near Villa de Arrayal, fl., fr., April 1841, G. Gardner 4021 (K barcode K000363236!; isolectotypes: B barcode B100367834!, BM barcodes BM001172132!, BM001172133!, G barcodes G00098261!, G00098262!, G00165012!, K barcode K000363237!, NY barcodes NY00247400!, NY00247401!, P barcode P02088022!, US barcode US00091574!).

Description.

Herbs ca. 30.0-150.0 cm tall, perennial, rhizomatous with a definite base, terrestrial to paludal to rooted emergent in flooded fields. Roots thin, fibrous, medium to dark brown, densely to sparsely pilose with medium to dark brown hairs, emerging from the short rhizome and from the basalmost nodes. Rhizomes short, light to medium brown, buried in the sand or ground. Stems prostrate, with erect to ascending apex, succulent, unbranched to little-branched at the base; internodes 1.9-10.7 cm long, green to vinaceous, glabrous to sparsely pilose or hispid, becoming glabrous with age, with a line of eglandular hairs opposite the leaf above, hairs hyaline. Leaves spirally-alternate, evenly distributed along the stems, sessile, the distal ones gradually reduced; sheaths 0.5-3.2 cm long, green to vinaceous, sparsely pilose to hispid, becoming glabrous with age, hairs hyaline, margins ciliate to hispid, with a line of eglandular hairs opposite the leaf above, hairs hyaline; lamina 4.2-17.4 × 0.7-1.3 cm, chartaceous, conduplicate, slightly falcate to falcate, green on both sides, drying light brown to olive-green on both sides, linear-lanceolate to lanceolate, sparsely pilose to hispid, becoming glabrous with age, rarely glabrous, base truncate to rounded, margins light green, ciliate to setose only at base, apex acuminate; midvein inconspicuous, slightly impressed adaxially, slightly obtuse abaxially, secondary veins 3-4(-5) pairs, adaxially inconspicuous to slightly conspicuous, light green, abaxially somewhat conspicuous. Inflorescences 1-(3) thyrsi, terminal or axillary from the uppermost nodes, thyrse with 16-38 verticillate cincinni, arranged in 2-9 whorls; peduncles 2.7-8.4 cm, with a mixture of eglandular (scabrid) and glandular, hyaline hairs; basal bract leaf-like, 2.4-7.2 × 0.3-0.9 cm, linear-lanceolate to lanceolate, sparsely pilose to hispid, rarely glabrous, base rounded, margins ciliate to setose only at base, apex acuminate, veins inconspicuous, concolorous to light green; cincinni bracts ca. 0.4-0.8 × 0.1-0.3 cm, ovate to broadly ovate, cup-shaped, light green to lilac, glabrous to pilose, base truncate, margins glabrous to sparsely ciliate, apex acuminate; cincinni 2-11-flowered, ascending, straight, peduncle 0.5-1.3 cm, light green to vinaceous to purple, with a mixture of eglandular (scabrid) and glandular or all glandular hyaline hairs, internodes 0.9-5.2 mm long, light green to vinaceous to purple, with a mixture of eglandular (scabrid) and glandular or all glandular, hyaline hairs; bracteoles ca. 1.8-4.1 × 2.8-4.2 mm, persistent, broadly ovate to depressed ovate, cup-shaped, light green to lilac or pink, sparsely pilose, base amplexicaul, non-perfoliate, margins glabrous to ciliate, apex acuminate. Flowers bisexual or male, enantiostylous, ca. 1.4-2.3 cm diam.; floral buds narrowly ovoid to ovoid, 2.6-5.3 × 1.2-2.4 mm, light green to pink to vinaceous; pedicels 2.2-7.3 mm long, light green to vinaceous to purple, with a mixture of eglandular (scabrid) and glandular or all glandular, hyaline hairs, erect and elongate in fruit; sepals 3.6-6.1 × 3.2-4.8 mm, triangular to ovate-triangular, cucullate, green to lilac to vinaceous to purple, with glandular to densely glandular, hyaline hairs, apex acuminate, margins hyaline light green to hyaline pink; petals equal, 0.7-1.2 × 0.6-0.8 cm, obovate to elliptic-obovate, slightly cucullate, pale lilac to lilac, purple or pink, rarely white, glabrous, base cuneate, margins entire, apex acute to obtuse; stamens 3, equal, filaments glabrous, gently curved at the apex, 6.2-9.4 mm long, pale lilac to lilac or white, anthers elliptic, 0.7-0.9 × 0.3-0.4 mm, connective lilac to white, anthers sacs white to lilac, pollen white; staminodes 3, equal, filaments glabrous, straight, 3.1-5.3 mm long, pale lilac to white, antherodes cordate, 0.7-0.9 × 0.8-0.9 mm, connective golden yellow, lobes conspicuous, cream-colored to pale yellow; ovary ellipsoid to broadly ellipsoid, 0.6-0.8 × 0.4-0.6 mm, 3-locular, white to light green, smooth, glabrous, style gently curved at the apex, ca. 4.8-6.2 mm, pale lilac to lilac or white, stigma truncate, white to lilac. Capsules 3.6-4.5 × 3.4-4.2 mm, 3-locular, 3-valved, subglobose to globose, apiculate due to persistent style, light brown when mature, glabrous, smooth. Seeds 1 per locule, 1.9-2.6 × 1.2-1.8 mm, reniform to broadly ellipsoid, strongly cleft towards the embryotega, ventrally flattened, testa dark brown to greyish brown, sparsely farinose, scrobiculate to foveolate, with ridges radiating from the embryotega, with a tan appendage that extends ventri-laterally to the embryotega and basally into the hilum; embryotega semilateral, relatively inconspicuous, without a prominent apicule; hilum linear, approximately the same length as the seed, in a deep depression.

Specimens seen.

BRAZIL. Bahia: Correntina, Chapadão Ocidental da Bahia, Islets and banks of the rio Corrente, 23 Apr 1980, R.M. Harley et al. 21668 (CEPEC, HRB, K, MBM, US); loc. cit., 21 Jan 1997, G. Hatschbach et al. 66044 (MBM); Goiás: Cavalcante, estrada rio Trairas/rio Custódio, km 2, 28 Nov 2006, G. Pereira-Silva & G.A. Moreira 11159 (CEN, RB); Colinas do Sul, fazenda Saracura, estrada de manutenção das novas linhas de transmissão Minacu/ Niquelândia, 8 Sep 1995, B.M.T. Walter et al. 2604 (CEN, RB); Goyaz, 1841, G. Gardner 4020 (K barcode K000363238, US barcode US00160560); Itumbiara, rodovia Itumbiara-Rio Verde, a 31 km de Itumbiara, 18 Apr 1978, G.J. Shepherd et al. 7415 (F ex UEC); Niquelândia, 27 km de Colinas em direção a Niquelândia, próximo ao rio Tocantinzinho, 6 May 1998, M.A. Silva et al. 3772 (IBGE, RB, US); Teresina de Goiás, km 12 da estrada GO-118, sentido Nova Roma, 29 April 1996, B.A.S. Pereira & D. Alvarenga 3027 (IBGE, RB); Mato Grosso: Novo Mundo, Parque Estadual do Cristalino, entrada para Fazenda J.J., 26 January 2008, D. Sasaki et al. 1934 (HERBAM, HURB, SPF); Minas Gerais: Ituiutaba, 26 May 1946, A. Macedo 760 (US); Tocantins: Conceição do Tocantins, rodovia TO-050, km 375, fazenda São José, próximo do rio Santa Isabel, 11 May 2000, G. Hatschbach et al. 70903 (MBM); Gurupi, próximo à Gurupi, 20 Apr 1978, R.P. Orlandi 73 (HRB, RB).

Distribution and habitat.

Murdannia gardneri is endemic to Brazil, being known from the states of Bahia, Goiás, Mato Grosso, Minas Gerais and Tocantins (Fig. 10 ). It grows in open sandy river banks or flooded grass fields, of the Cerrado domain.

Phenology.

It was found in bloom and fruit throughout the year.

Conservation status.

Murdannia gardneri possesses a EOO of ca. 497,658.992 km2 and a AOO of ca. 20,000.000 km2. Most of the known collections are concentrated in central Brazil, where the native vegetation is commonly removed to give place to livestock. This is especially common in the Cerrado domain, due to its savanna vegetation being easier to remove than the dense rainforests of the Amazon and Atlantic Forest domains. Thus, we believe that Murdannia gardneri should be considered Nearly Threatened.

Nomenclatural notes.

When describing Aneilema gardneri , Seubert (1855) lists two collections from G. Gardner (4020 and 4021). As aforementioned, Gardner 4020 consists of a mixture of Murdannia burchellii and Murdannia gardneri . Fortunately, the same is not true for Gardner 4021. Furthermore, the Gardner 4020 specimen at P was designated by us as the lectotype for Aneilema gardnei var. glabrior . Thus, we designate a specimen at K as the lectotype for Aneilema gardneri .

Discussion.

Murdannia gardneri is morphologically similar to Murdannia burchellii and Murdannia paraguayensis due to their phyllotaxy and by the number of cincinni per inflorescence. It is morphologically more similar to Murdannia burchellii due to the posture of the pedicels at post-anthesis and when fruiting, general floral and capsule morphology, and due to the hilum being positioned in a deep depression. Nevertheless, both species can be easily differentiated based on the insertion of the cincinni in the main axis of the inflorescence (alternate to subopposite in Murdannia burchellii vs. verticillate in Murdannia gardneri ), the ornamentation of the testa (costate to slightly rugose vs. scrobiculate to foveolate), robustness of the plants (delicate vs. robust, branching pattern (densely branched at base vs. unbranched to little-branched), leaf-blade consistency (chartaceous vs. succulent), and some indumentum differences. On the other hand, Murdannia paraguayensis can be readily differentiated from Murdannia gardneri by its 1-flowered cincinni (vs. many-flowered in Murdannia gardneri ), deflexed pedicels post-anthesis and when fruiting (vs. erect), filaments with minute glandular hairs (vs. glabrous), gynoecium and capsules with glandular hairs (vs. glabrous), capsule oblongoid to broadly oblongoid (vs. subglobose to globose), locules 2-seeded (vs. 1-seeded), and hilum in a shallow depression (vs. in a deep depression) (Table 1 ).

Figures

Figure 3. Murdannia gardneri (Seub.) G. Brueckn. A Inflorescence, showing the verticillate cincinni and open lilac flowers B detail of the inflorescence, showing the ascending and straight cincinni C flooded grassland in the state of Minas Gerais. Photographs A-B by W. Milliken, C by I. L. M. Resende.

Figure 4. Murdannia gardneri (Seub.) G. Brueckn. Isolectotype of Aneilema gardneri (P barcode P 02088022). Photograph courtesy of the Museum National d'Histoire Naturelle, Paris.

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.