Nepenthes justinae

Nepenthes justinae

Synonymy

Nepenthes justinae Gronem., Wistuba, Mey & Amoroso in Plants (Basel) 5(2) (23): 6 (-10, fig. 3, 4). 2016 [The specific epithet honors Justina Yu, the mayor of the municipality of San Isidro, Davao Oriental Province, Mindanao Island. Due to Justina Yu’s support and dedication, the Mount Hamiguitan Wild Life Sanctuary became a protected national park and was declared a UNESCO World Heritage Site in 2014.B]. sec. Gronemeyer & al. 2016 wfo-0001302568
      Type: Philippines, Mindanao Island, Mount Hamiguitan, 17.08.2004, V.B. Amoroso, holotype CMUH00003606 (CMUH) designated by Gronemeyer & al. 20161
  • 1. Gronemeyer, T., Suarez, W., Nuytemans, H., Calaramo, M., Wistuba, A., Mey, F. S. & Amoroso, V. B. 2016: Two new Nepenthes species from the Philippines and an emended description of Nepenthes ramos. – Plants (Basel) 5(2) (23): 1-15

Description

The stem is up to 4 m long, cylindrical in transection, 5–8 mm in diameter. The average internode length is 6 cm (might be longer in climbing stems).
Leaves of the climbing stem are elliptic to ovate, 18 cm long and 11 cm wide, with 3 equally distributed longitudinal veins on each side of the midrib and numerous pinnate veins running obliquely towards the leaf margins. The apex of the lamina is acute, the base attenuate and forming a sessile, narrowly winged petiole of 6 cm in length. Pitchers are on tendrils being up to 21 cm long. The tendrils are curled and are covered with short, brown hairs, about 1 mm long.
Lower pitchers are bulbous in the lower ⅔ and slightly infundibulate in the upper ⅓. They are 9 cm long and 2.5 cm wide in the upper half and 3.5 cm wide in the lower half. The pitcher narrows slightly towards the opening. Wings run down the front of the trap, fringed with filaments up to 3 mm long and 2 mm apart. The pitcher opening is distinctively oblique, up to 2 cm wide and acuminates towards the lid. The peristome is slightly flattened, up to 0.5 cm wide, not crenelated and densely lined with ribs having very small conspicuous teeth at the margin. The peristome is elongated into a neck towards the lid, which is cordate and 1.5 × 2 cm wide. Nectar glands are monomorphic and large with the largest glands located in a cluster distally to the midline, smaller glands cover approx. 60% of the lid surface. A keel, 3 mm wide, is present on the underside of the lid. The spur is 3 mm long and bifid at the tip but not completely branched.
The exterior of the lower pitchers is creamy-yellow, with narrow purple blotches. The interior of the pitcher is uniformly greenish-white and sometimes lined with angular blotches of purple. The peristome is dark red and unevenly yellow striped. The whole surface of the lower pitchers is covered with dense, very short brown hairs.
Upper pitchers are 17 cm long and 3.5 cm wide in the upper ⅔ and 4 cm wide in the lower ⅓. The lower ⅓ is separated by a distinct rim from the upper ⅔ of the pitcher. The pitcher narrows slightly towards the middle section before it widens towards the oblique pitcher opening; the latter being 2.5 cm wide. Wings run down the front of the trap, fringed with filaments up to 3 mm long and 4 mm apart. The wings are sometimes reduced to ribs. The peristome is slightly flattened, up to 1 cm wide, elongated into a short collar and densely lined with ribs having no visible teeth at the margin. The lid is cordate and 3 × 4 cm wide. A rounded appendage of 3 mm on a keel is present; the spur is 4 mm long, unbranched but is occasionally bifid at the tip. The nectar gland distribution, coloration and indumentum are consistent with the lower pitchers.
The female inflorescence is a panicle composed of a 40 cm-long scape and an additional 25 cm rachis. The partial peduncles are 2-flowered and 12 mm long. The pedicels are 10 mm long bearing flowers with 4 mm wide tepals. The male inflorescence is unknown.
NB: The given dimensions are based on the holotype specimen and of the specimens at ULM. The dimensions of the pitchers may be larger in all respects. At the type locality upper pitchers up to 25 cm large have been recorded. Dimensions of the female inflorescence were recorded from the specimen at ULM as the holotype does not contain inflorescences.A

Conservation

As N. justinae is endemic to Mt. Hamiguitan, it is assessed here as vulnerable (VU) applying the IUCN Redlist criteria.A

Distribution (General)

Philippines, Mindanao Island, Davao Oriental province, Mt. Hamiguitan.A

Bibliography

A. Gronemeyer, T., Suarez, W., Nuytemans, H., Calaramo, M., Wistuba, A., Mey, F. S. & Amoroso, V. B. 2016: Two new Nepenthes species from the Philippines and an emended description of Nepenthes ramos. – Plants (Basel) 5(2) (23): 1-15

Specimens

CountryDateCollector + collecting numberHerbariaTypeScanDerivatives
Philippines, Mindanao Island, Mount Hamiguitan, 17.08.2004, V.B. Amoroso, holotype CMUH00003606 (CMUH)
Citation: Philippines, Mindanao Island, Mount Hamiguitan, 17.08.2004, V.B. Amoroso, holotype CMUH00003606 (CMUH)