Nepenthes Talangensis - Description

Description

Nepenthes talangensis is a climbing plant growing to a height of 3 m. The stem is up to 0.5 cm in diameter and has internodes up to 10 cm long that are cylindrical-angular in cross section. The stem may be branched and is yellowish-green in colour.

An offshoot from an old climbing stem (left) and a closeup of a rosette pitcher from the same plant (right) with well-developed fringed wings

Leaves are coriaceous and sessile. The lamina (leaf blade) varies in shape and may be linear, lanceolate, or slightly spathulate. It measures up to 16 cm in length by 3 cm in width. The lamina has an acute or obtuse apex and an attenuate base that clasps the stem. Two to three longitudinal veins are present on either side of the midrib. Pinnate veins are irregularly reticulate. Tendrils are up to 30 cm long. The lamina is dark green throughout, whereas the midrib and tendril are yellowish-green like the stem.

Rosette and lower pitchers are only produced briefly before the plant starts to climb. They are either entirely ovate or only ovate in the upper half and infundibular below. They often narrow just below the peristome. Terrestrial pitchers grow to 10 cm in height by 6 cm in width. A pair of fringed wings (≤10 mm wide) usually runs down the ventral surface of the trap, bearing filaments up to 8 mm long, although these wings may be absent altogether or only extend for a portion of the trap's length. The pitcher mouth is round and positioned horizontally in the front two-thirds, rising at the rear to form a short neck. The peristome is flattened, strongly incurved, and measures up to 15 mm in width. It bears ribs up to 0.8 mm high and spaced up to 1 mm apart. These ribs terminate in distinct teeth (≤3 mm long) on the inner margin of the peristome. The inner portion of the peristome accounts for around 78% of its total cross-sectional surface length. The peristome forms a short neck at the rear, where the teeth form two parallel rows. The inner surface is wholly glandular; there is no waxy zone. The pitcher lid or operculum is ovate to elliptic and has a cordate base. It measures up to 6 cm in length by 5 cm in width. It bears no appendages on its lower surface. A flattened spur measuring up to 5 mm in length is inserted near the base of the lid. It may or may not be branched. Lower pitchers are typically light yellow to olive green and speckled with red or purple. The inner surface is a light shade of yellow. The peristome is generally yellow or orange in freshly opened traps, later becoming dark red to purple as the pitcher matures. The upper surface of the lid is often yellow with orange to purple blotches, whereas the underside may be completely red, although this is not always the case.

Intermediate pitchers showing the colour variation exhibited by this species

Upper pitchers are either narrowly infundibular in the basal half of the pitcher cup and swollen above or infundibular throughout. A constriction is present just below the peristome. Aerial traps reach 12 cm in height by 6 cm in width. In upper pitchers, the wings may be partially developed near the pitcher mouth, or they may be reduced to ribs. The peristome reaches up to 24 mm in width and is similarly incurved to that found in terrestrial traps. Other parts of upper pitchers are similar to their lower counterparts. Upper pitchers exhibit a similar pigmentation to lower pitchers, but are typically lighter.

Nepenthes talangensis has a racemose inflorescence up to 14 cm long, of which the peduncle constitutes up to 5 cm and the rachis up to 9 cm. The peduncle has a basal diameter of 2 mm. Flowers are borne solitarily on pedicels (≤10 mm long) with simple bracts. Tepals are elliptic and up to 4 mm long. Female and male inflorescences have a similar structure.

A sparse but persistent indumentum of simple, white hairs is present on most parts of the plant. The density of hairs on the pitchers may be so low that they appear glabrous. The laminar margins are lined with red, brown or white hairs measuring up to 3 mm.

Nepenthes talangensis varies little across its restricted range and has no infraspecific taxa.