Rafflesia parvimaculata Sofiyanti, Mat-Salleh, Khairil, Zuhailah, Mohd. Ros, Burslem, 2016

Sofiyanti, Nery, Mat-Salleh, Kamarudin, Mahmud, Khairil, Mazlan, Nor Zuhailah, Ros, Mohd., Hasein, Albukharey & Burslem, David F. R. P., 2016, Rafflesia parvimaculata (Rafflesiaceae), a new species of Rafflesia from Peninsular Malaysia, Phytotaxa 253 (3), pp. 207-213 : 208-210

Rafflesia parvimaculata Sofiyanti, Mat-Salleh, Khairil, Zuhailah, Mohd. Ros, Burslem sp. nov. ( Figs. 2A–F )

Rafflesia parvimaculata has numerous small warts on the perigone lobe and the window. These warts have a well-spaced arrangement on both structures. Ramenta are slender, unbranched, capitate, white in color and densely arranged. These unique characters are the characteristics of this new species.

Type:─ MALAYSIA: Peninsular Malaysia, Pahang, Lata Jarum. 03 55.92º N, 102 01.99 º E. 29 December 2005, LJ4 a1. Male. (Holotype UKMB!).

Holoparasite. Mature bud ca. 15 cm in diameter, reddish orange ( FIG. 2A ). Bracts black, thin and scaly, innermost largest, outermost smallest. Flower up to 41 cm in diameter when fully mature ( FIG. 2B ). Perigone lobes 5, innermost smallest ca. to 15 cm long and 10 cm wide, outermost widest ca. to 21 cm long and 15 cm wide, bright red. Warts cover perigone lobes, whitish light red, 84–91 warts per lobe, distribution well-spaced, variable in size, 4–13 mm long, 3–13 mm wide. Diaphragm whitish light brown, pentagonal, with aperture in the middle, 6.5–7.5 cm wide from aperture to the base of perigone lobes, covered with small and unclear warts, ca. to 3 mm wide. Aperture 7–7.5 cm in diameter. Perigone tube up to 13 cm high from base of tube towards aperture. Window pattern inside the perigone tube is well spaced, elongated and densely arranged warts occur near the aperture, rounded and well-spaced warts toward ramenta, wart shape irregular ( FIG. 2C ). The shape of warts under window towards ramenta are polymorphic and mostly mushroom-shaped, with a white tip. Ramenta white head, capitate, slender, 9–11 mm long, unbranched ( FIG. 2D ). Disk 10 cm in diameter, dark brown at the edge, light brown in the middle and bearing processes ( FIG. 2E ). Processes 25, brown, darker towards tip and lighther towards base, star-shaped tip, up to 2 cm long, wider at the base ca. 5 mm wide. Column ca. 8 cm wide, deeply grooved, triangular sulci, no hairs. Annulus 1, dark brown almost black, 3–4 mm wide. Anthers 24, 4 mm in diameter, arranged in a circle at lower surface of disk ( FIG. 2F ). Pollen grain ( FIG. 2G ) with 1 aperture, monoporate, prolate spheriodal, length of equatorial axis 16.68 ±2.56 μm, length of polar axis 17.51±2.55 μm.

Distribution and ecology: — Rafflesia parvimaculata is an endoparasitic species that grows on the root or stem of Tetrastigma sp. ( Vitaceae ). The specimen of Tetrastigma was not collected. This new species was collected in hill dipterocarp forest at an elevation of 200 to 400 m a.s.l. in the Lata Jarum Forest, Pahang, Peninsular Malaysia. A photograph of a Rafflesia from Perak (Peninsular Malaysia) (Courtesy of Siti Munirah M.Y, FRIM that has been deposited in the Kew Herbarium shows similar morphological characters to this new species, especially in the presence of numerous white small warts on the perigone lobes. Therefore we tentatively suggest that Rafflesia parvimaculata may also occur in Perak, although further exploration in this region is required to verify this conclusion.

Etymology: —The specific epithet refers to the numerous small warts on the perigone lobes. It is derived from the Latin parvi (small) and maculate (stain, spot, wart).

Phenology: —Flowers were observed by us in February, March, September and December. Variation in the size of buds observed in February suggests that the flower can be found throughout the year independently of season.

Conservation status: —All members of Rafflesia are totally protected plants in Malaysia due to its endangered status. The only known locality of R. parvimaculata in Lata Jarum, Pahang, Peninsular Malaysia is a Forest Reserve where logging and other forms of disturbance are currently prohibited. Within the Lata Jarum Forest Reserve, the Forestry Department manages public education events, research and visits to flowering Rafflesia plants by tourists. These visits are supervised carefully to avoid disturbance to Rafflesia buds. During fieldwork we found a total of seven Rafflesia populations (defined as all Rafflesia infecting a single host plant) of which six populations were R. cantleyi and only one was R. parvimaculata . A total of 19 individuals of R. parvimaculata was found in the study site and, in addition, five swollen sections, with a diameter of about 1–2.5 cm, occurred on of the Tetrastigma stem. These swellings may indicate that the stem is infected, and represent sites from which new Rafflesia flower buds will emerge. Flower bud size of R. parvimaculata ranged from 3 cm to 15 cm in diameter. A total of four flowers bloomed during our visits, but only two of them were collected to avoid over-collection of this rare species.

Figures

FIGURE 2. Morphology of R. parvimaculata sp. nov.A. Mature bud, B. Male flower fully open, C. Inner side of floral perigone tube of male flower, D. Unbranched ramenta, E. Upper surface of disk showing processes of male flower, F. Lower surface of disk showing anthers (insert: pollen grain). Scale bars: A, C 5 cm; B 10 cm; D 1 cm; E, F 2,5 cm (Specimens: A not collected; B–E LJ4 a1; F LJ4 f3).