Habenaria crocodilium Hermans, Kew Bull. 76: 47 (2021).
Description:
Erect terrestrial herb 20 - 40 cm tall without the inflorescence, with two ellipsoid tubers, c. 2.5 - 3 cm long, hirsute, roots wiry, clustered around the base of the stem c. 3 mm in diam. Stem not branched, 10 - 30x 0.5 -0.8 cm with 3 - 4 leaf-like sheaths along its length dividing it into short segments, becoming progressively larger toward the top, 3 - 8x1 - 3.5 cm. Leaves spreading, 3 - 5, arranged spirally along the stem forming an apical crown, lanceolate, 7 - 18 x 1.2 - 2.8 cm flat, somewhat fleshy, attenuate, subcordate at the base, shortly petiolate, somewhat serrate at the margins, pale green, darker along the veins. Inflorescence terminal, c. 15 cm, laxly racemose with c. 15 flowers. Peduncle c. 10 cm, 2 - 4 mm in diam., with 1 - 2 ovate sheaths, attenuate, subcordate at the base, hirsute, c. 20 x 8 mm. Floral bracts lanceolate, conduplicate, attenuate, dentate to hirsute at the dorsal ridge and basal margins, 11 - 16 x 2.1 - 3.2 mm. Flowers evenly distributed along the rachis, spreading, overall c. 25 x 25 mm, all segments pale green becoming paler towards the centre, the veins a little darker, column white, pollinia yellow. Pedicel and ovary fusiform, sharply ridged, densely denticulate, pale green, 15 - 21 x 1.2 - 2.5 mm. Dorsal sepal cucullate, arching over the column, lanceolate, 10 - 12 x 4.5 - 5 mm, the exterior echinate along the mid-vein. Lateral sepals spreading, obliquely ovate, 11.2 - 11.6 x 6 - 6.2 mm, almost flat, the apex a little mucronate, the veins thickened. Petals bifid to the base, posterior lobe (11 -12.1 x 1.1 - 1.4 mm) adnate to dorsal sepal, ligulate-linear, attenuate, anterior lobe (9.3 - 12 x 1.2 - 1.3 mm) spreading to curved. Lip 3-lobed, all lobes pendent — recurved, the mid-lobe more strongly recurved especially at the tip, linear falcate, attenuate, mid-lobe (11 - 14.2 x 0.7 - 0.9 mm), lateral lobes (15.7 - 14.3 x 1.1 - 1.4 mm); spur clavate, tubular in the basal half, thickened and laterally compressed in the apical half, 12.3 - 13.1 x 1.2 - 1.9 mm. Column c. 5 mm high, 9 mm long, anther loculi narrowly ovoid, anther channels distinctly up-curved, c. 6.7 x 0.3 mm, stigmatic lobes linear incurved, staminodes bilobed, verrucose, pollinarium c. 8 mm long.
Etymology:
Referring to the type locality near a crocodile enclosure and the resemblance of the column and dorsal sepal to the head of a crocodile, plus the numerous teeth on the flowers and ovary.
Recognition:
Habenaria crocodilium is distinct in being a tall plant with spirally arranged leaves forming an apical crown, having an inflorescence borne on a short peduncle, denticulate floral bracts and flowers that are large for the genus in Madagascar, with denticulate ovary ridges, bifid petals with equal lobes, a lip with three equal descending lobes, a slightly flattened clavate spur shorter than the pedicellate ovary, and long and strongly up-curved anther channels. Amongst the large and medium-sized-flowered species of Madagascar and mainland Africa it is somewhat similar in flower shape to H. beharensis Bosser (1969a: 293), H. cirrhata (Lindl.) Rchb.f. (Reichenbach 1865: 180) and H. clavata (Lindl.) Rchb.f. (Reichenbach 1865: 180) but it is very distinct in its habit with its leaves borne along the stem (vs apical), and much smaller flowers (half the size) with a much shorter and differently shaped spur. It has a similar spur and anther-channel shape to H. cornuta Lindl. (Lindley 1837: 208) but again differs by its distinct habit, smaller flowers and differently proportioned lip and petals. The short clavate spur is also found in H. cochleicalcar Bosser (1969a: 294), and its flowers are also similar in size but the habit of H. crocodilium is different and the lobes of the petals and lip are of different proportions (unequal vs equal). It is similar in plant habit to H. tianae P.J.Cribb & D. L. Roberts (2008: 199) but its flowers are smaller by at least ⅓, the spur much shorter (12 mm vs 12 cm) and the anther channels a different shape. None of the other species listed above have the pronounced echinate-denticulate ovary, floral bract and exterior of the dorsal sepal.
Habitat:
Humid evergreen forest, on riverbanks and wet areas. Elevation 800 - 950 m.
Flowering time:
July to September.
Distribution:
Known from two localities in Toamasina province, the type location in the eastern forest and another in NE Madagascar
References:
New species in Orchidaceae from Madagascar by Johan Hermans, Landy Rajaovelona & Phillip Cribb. KEW BULLETIN Published online: 15 March 2021.; POWO (2022). "Plants of the World Online. Facilitated by the Royal Botanic Gardens, Kew. Published on the Internet; http://www.plantsoftheworldonline.org/ Retrieved 28 November 2022."
Images:
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Read more of cultivation of Habenaria nyikana Rchb.f.
Culture:
Light:
2500-4000 fc. Light should be filtered or diffused, and plants should not be exposed to direct midday sun. Strong air movement should be provided at all times.
Temperatures:
Summer days average 82F (28C), and nights average 65-66F (18-19C), with a diurnal range of 16-17F (9-10C). Because of the range in habitat elevation, plants may adapt to temperatures 3-5F (2-3C) warmer or cooler than indicated in the preceding climate table.
Humidity:
80-85% in summer and early autumn, dropping to 60-65% most of the remainder of the year, with only about a one-month transition period between the wet and dry seasons. High humidity is probably not required, or even desired, for these plants.
Water:
Rainfall in the region is heavy from late spring into early autumn. Averages then drop rather quickly into a dry season that lasts from midautumn to late spring. A dry rest in winter is important, and too much water in winter may prove to be fatal.
Fertilizer:
1/4-1/2 recommended strength, applied weekly when plants are actively growing. Many growers prefer to use a balanced fertilizer throughout the year; but others use a high-nitrogen fertilizer from spring to midsummer and then switch to one high in phosphates in late summer and autumn.
Rest period:
Winter days average 72-75F (22-24C), and nights average 53-55F (12-13C), with a diurnal range of 18-20F (10-11C). Growers are reminded that plants may adapt to temperatures 3-5F (2-3C) warmer or cooler than indicated. Rainfall in the habitat is low in winter, but some additional moisture is available from dew. Water for cultivated plants should be reduced in winter. In most growing areas, infrequent light waterings should provide the necessary dry rest while preventing the potting medium from becoming too dry. Fertilizer should be eliminated until new growth starts and heavier watering is resumed in spring.
Growing media:
Hawkes (1965) stated, "The cultural requirements of the Habenarias are as varied as are the species themselves, depending primarily upon the place or origin of the particular individual involved. A rich, porous compost, such as that suggested for Phaius and the like, is recommended, and in most cases it is suggested that the plants be grown in pots, rather than in the ground, unless a particularly well-set-up outdoor garden is available. Very perfect drainage is absolutely essential for any degree of success with these plants, and as a rule, they should be repotted and the subterranean tubers divided on an annual or at least biennial basis, for best results. Most of the Habenarias in cultivation today do well in a rather brightly lighted situation in the greenhouse, or--during sufficiently warm weather--when set outside, in their containers. While they are in active growth, they benefit by liberal applications of water and fertilizing materials, but upon the cessation of flowering--when the leafy shoots commence to die back (for all of these orchids are normally deciduous)--moisture should largely be withheld, and fertilizing stopped, in order to allow the tuberous roots to ripen properly. During this rest period (which will often continue for a period of several months), only enough water should be given the plant that the compost in which it is growing does not become excessively dry and hard-baked. When the parts above ground have withered thoroughly, the tubers may be removed and divided, being thereupon repotted and watered only very slightly until the new shoots once again appear above the surface." The compost generally recommended for Phaius species consists of a mix of equal parts soil, rotted cow manure, and peat or sphagnum moss. A top dressing of additional rotted cow manure is added each spring when growth resumes.
References:
This information is quoted from a Charles and Margaret Baker culture sheet, with permission from Troy Meyers
Habenaria longa Cordem., Fl. Réunion: 261 (1895).
Description:
Ne pas confondre avec Habenaria praealta
Habitat:
No data.
Distribution:
Réunion
References:
Flore de l'île de la Réunion 1895 page 261
Habenaria uncinata Szlach. & Olszewski, Fl. Cameroun 34: 160 (1998).
Homotypic Synonyms:
Ceratopetalorchis uncinata (Szlach. & Olszewski) Szlach., Górniak & Tukallo, Richardiana 3: 162 (2003).
Description:
Stem 76 cm tall, erect, robust, glabrous, leafy throughout its length. Leaves 13, up to 11.5 cm long and 4 cm wide, broadly lanceolate to ovate-lanceolate, acute slightly recurved; decreasing in size up the stem. Inflorescence 34 cm long, ca. 60-flowered, dense, cylindrical. Flowers relatively small. Floral bracts up to 16 mm long, thin, densely pubescent outside and along margins. Pedicel and ovary up to 30 mm long, glabrous. Dorsal sepal 6 mm long, 3 mm wide, oblong-ovate, cochleate, obtuse, cucullate, sparsely glandular outside. Petals bipartite almost to the base; anterior lobe 9 mm long, 1.7 mm wide, narrowly lanceolate, acuminate, falcate, minutely papillate at the base; posterior lobe 6 mm long, 1 mm wide, narrowly oblan-ceolate, subobtuse, falcate, minutely papillate. Lateral sepals 9-10 mm long, 6.5-7 mm wide, obliquely broadly obovate to triangular, acute, slightly cochleate, thickened at the apex, sparsely glandular outside. Lip tri-partite nearly to the base, slightly thickened, glabrous; the middle lobe 12 mm long, less than 1 mm wide, linear, acute, side lobes 6-6.5 mm long, 0.7 mm wide, linear-lanceolate, acute, pendent. Spur 20-25 mm long, ca. 2 mm in diameter at the apex, curved upwards like a horn, filiform, distinctly swollen in the apical third, subacute. Rostellum minutely ciliolate. Antherophores ca. 3-4 mm long.
Habitat:
Not recorded. October.
Notes:
This species differs from another small-flowered member of the genus, Habenaria stenorhynchos Schltr., by having 20-25 mm long, uncinate spur, shorter lobes of petals and pedicel shorter than ovary.
Cultivation:
As given for the genus.
Distribution:
The Democratic Republic of Congo (Zaire).
References:
Orchidaceae of West-central Africa, vol. 1, Gdansk University Press Gdansk 2010
Habenaria tanzaniyana J.M.H.Shaw, Orchid Rev. 122(1306, Suppl.): 39 (2014).
Homotypic Synonyms:
Bilabrella usambarae Kras & Szlach., Polish Bot. J. 53: 100 (2008).
Description:
Vegetative parts unknown. Pedicel and ovary 11.5 mm long, glabrous. Sepals all reflexed. Dorsal sepal 6 mm long, 1.8 mm wide, oblong elliptic- obovate, obtuse, concave. Petals bilobed; posterior lobe long 5.1 mm, wide 1.8 mm, 7-nerved, rounded, with apex; anterior lobe 6 x 0.3 mm, narrower than the posterior, lobules, oblong, triangular. Posterior and anterior lobes glandular to half-length. Lateral sepals 7.5 x 4 mm, obliquely elliptic-obovate, concave, finished by apex long 1 mm. Lip trilobed to base; middle lobe 0.5 mm wide, linear, obtuse; lateral lobes usually slightly shorter, 4.7 x 1 mm, linear. Spur 16 mm long, curving forwards with one twist about the middle, inflated in apical third. Anther 2.5 mm long; connective rounded, shortly apiculate; antherophores 5.5 mm long, slender, slightly upcurved apically. Stigmaphores 4 mm long, narrowly cylindrical, truncate. Rostellum middle lobe shorter than the connective. Auricles bilobed.
Etymology:
In reference to the locus classicus of the type specimen.
Habitat:
No records.
Note:
Similar to Habenaria disparilis Summerh. but the anterior petal lobes are not deeply lobulate. One of the lobules is rounded and the other is triangular; the rostellum middle lobe is shorter than the connective. Another similar species is Habenaria thomsonii Rchb.f., but Habenaria tanzaniyana J.M.H.Shaw differs from the latter by the lobules of the petals and narrow spur, longer than the pedicel and ovary.
Distribution:
Tanzania
References:
Polish Bot. J. 2008
