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| Durio gerikensis M.N.Faizal, Edward, Latiff & Hadrul, in Ghazalli, Hashim, Besi, Mat-Esa,... et Latiff, 2022. |
Abstract
A new species Durio gerikensis (Malvaceae) is described from Hulu Perak, Peninsular Malaysia, it can be easily recognised in the field by its reddish-pink flowers and small (6–7.5 cm in diameter), golden yellowish to pale yellow fruits with persistent calyx. It is unique from all the congeneric taxa by having two to four valved fruits with arilless seeds. Morphologically, Durio gerikensis is similar to D. lanceolatus Mast. (Masters 1875:499) and D. singaporensis Ridl. (Ridley 1916: 143) but they differ in their leaf, flower and fruit characteristics.
Keywords: Eudicots, arilless Durio, red-pink flowers, persistent calyx, Peninsular Malaysia
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| Durio gerikensis M.N.Faizal, Edward, Latiff & Hadrul, A) tree (habit) at the type locality. B) branching pattern. C) leaves. D) bark. E) abaxial surface of the leaves. F) adaxial surface of the leaves. Photographs (A) by Mohd Masri Saranum; (B–F) by Mohd Norfaizal Ghazalli. |
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| Durio gerikensis M.N.Faizal, Edward, Latiff & Hadrul, A) fruiting leafy twig. B) different fruit stages, and arilless seeds. C) arilless seeds (close up). D) dehisced fruits with three lobes (left) and one lobe (right). (E) immature fruit (F) mature and dehisced fruit with persistent calyx. Photographs A–F by Mohd Norfaizal Ghazalli. |
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| Durio gerikensis M.N.Faizal, Edward, Latiff & Hadrul, A) inflorescence young flower buds. B) inflorescences flower buds on branches. C) inflorescences on branch. D) flowers in fasciculate cymes. E) epicalyx. F) opened epicalyx. G) calyx. H) calyx adaxial view. I) stamens in 5 phalanges. J) petals. K–L) pistil (ovary, style and stigma) and pedicel. N) full part of the pistil and pedicel. O) portion of style and stigma at the end of style. P) ovary. Q) phalanges of stamens. R) close up of stamens. S) dehisced anthers. Photographs A–C by Mohd Norfaizal Ghazalli; D–S by Edward Entalai Besi. |
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| Durio gerikensis M.N.Faizal, Edward, Latiff & Hadrul, A) fruit. B) fruit attached to the branch. C) abaxial view of the fruit. D) dehiscent fruit. E) leaf morphology with dentate-lepidote trichome, 18–20-armed stellate trichomes, dentate-lepidote scales and 5-armed stellate trichomes with a central cushion. Illustrated by Zulkifli Zainol Alam. |
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| Durio gerikensis M.N.Faizal, Edward, Latiff & Hadrul, A) opened epicalyx. B) intact epicalyx. C) calyx adaxial view. D) calyx. E) stamen. F) ovary. G) petal. H) anther. I) pistil and pedicel. J) phalanges of stamen. K) inflorescence. L) flower bud. Illustrated by Zulkifli Zainol Alam. |
Durio gerikensis M.N.Faizal, Edward, Latiff & Hadrul, sp. nov.
Diagnosis:—Durio gerikensis morphology is partially similar to D. lanceolatus. It has oblong-lanceolate leaves (vs. elliptic-lanceolate to ovate), base acute (vs. acute to round); flowers in 6–28 flowered cymes, on young to older branches, reddish pink petals (vs. 3–4 flowered cymes, on older branches, yellow petals); and its fruit is arilless, not edible and contains two to four valves (vs. creamy aril, almost tasteless and unpalatable). When compared to D. singaporensis fruits (another species with arilless fruits) it has 5-lobed, white leathery aril which later dried and not edible. Additionally, D. gerikensis fruits can be readily differentiated from both D. lanceolatus and D. singaporensis with the persistent calyx on the mature fruits and the four-valved fruits (vs. early caducous calyx and more than 4- valved fruits).
Etymology:—Named after the type locality, Gerik, Hulu Perak, Peninsular Malaysia.
Mohd Norfaizal Ghazalli, Mohamad Hadrul Hashim, Edward Entalai Besi, Muhammad Ikhwanuddin Mat-Esa, Ahmad Zaki Zaini, Mohd Masri Saranum, Salmaniza Salleh, Rosliza Jajuli, Muhammad Shafie Md Sah, Noraini Talip, A. Latiff. 2022. Durio gerikensis (Malvaceae), A New Arilless Durio from Hulu Perak, Malaysia. Phytotaxa. 543(1); 21–30. DOI: 10.11646/phytotaxa.543.1.2
