Nepenthes Mikei - Description

Description

Nepenthes mikei is a climbing plant growing to a height of 7 m. The stem, which may be branched, is up to 0.4 cm in diameter and has cylindrical to angular internodes measuring up to 9 cm in length. Plants from Mount Bandahara are known to produce offshoots from short underground rhizomes. Nepenthes mikei is noted for rapidly transitioning from a rosette to a climbing stage; sequential internodal lengths of 2–3 mm and 10 cm have been recorded.

Leaves are sessile and coriaceous in texture. The lamina (leaf blade) is linear and measures up to 10 cm in length by 2 cm in width. Its apex may be acute or obtuse and it is abruptly contracted at the base, clasping the stem for around half of its circumference. One to two longitudinal veins are present on either side of the midrib, while pinnate veins are irregularly reticulate. The upper surface of the lamina is typically green, but may be red if exposed to direct sunlight. Tendrils are up to 15 cm long.

Rosette and lower pitchers are ovate in the basal third to quarter of the pitcher cup, becoming approximately cylindrical above and infundibular towards the pitcher mouth. They are relatively small, growing to only 12 cm in height by 3 cm in width. A pair of wings (≤4 mm wide) typically runs down the ventral surface of the pitcher cup, with fringe elements measuring up to 8 mm in length. These wings may be reduced to ribs in some plants. The glandular region on the inner surface is restricted to the ovate portion of the pitcher cup. The glands are small (0.2–0.3 mm in diameter) and occur at a density of around 150–180 per square centimetre. The waxy zone is well developed and eye spots may occasionally be present on the rear inner surface, visible through the opening. The peristome is sub-cylindrical to cylindrical and up to 4 mm wide. It bears ribs up to 0.1 mm high and spaced 0.2 mm apart, which terminate in teeth up to 0.4 mm long. The inner portion of the peristome accounts for around 51% of its total cross-sectional surface length. The pitcher lid or operculum is ovate and has a cordate base. It measures up to 3 cm in length by 2.5 cm in width and does not bear any appendages. The underside of the lid has an even distribution of small (0.1–0.2 mm in diameter) convex glands, occurring at a density of about 40/cm2. The spur, which is inserted near the base of the lid, is up to 7 mm long and may be simple, forked, or fasciculate with up to 12 branches.

Upper pitchers are ovate in their basal third to fifth, becoming cylindrical above and infundibular towards the peristome. They are smaller than their lower counterparts, reaching only 8 cm in height by 2 cm in width. Wings are always reduced to ribs. In other respects, upper pitchers are similar to the lower traps.

Nepenthes mikei has a racemose inflorescence measuring up to 18 cm in length by 1.8 cm in diameter. The peduncle itself may be up to 8 cm long by 1 mm wide in female plants, and up to 3 cm long in males. The rachis is up to 8 cm long. The inflorescence bears one-flowered pedicels (≤6 mm long), which may be bracteoleate. The oblong-lanceolate tepals measure up to 4 mm in length. Fruits are up to 22 mm long.

Most parts of the plant are glabrous. An indumentum of short, white or yellowish hairs is usually present on the tendrils and some parts of the inflorescence. This indumentum is a mixture of simple and stellate hairs. Caducous hairs cover developing pitchers and other parts.