J. Bio. & Env. Sci. 2019

Journal of Biodiversity and Environmental Sciences (JBES) ISSN: 2220-6663 (Print) 2222-3045 (Online) Vol. 15, No. 5, p. 113-124, 2019 http://www.innspub.net

RESEARCH PAPER OPEN ACCESS

Floral diversity of the lowland ultrabasic forest in the Northern Sierra Madre Natural Park, Isabela, Luzon,

Ma Visitacion D. Guingab*

Faculty of the College of Forestry and Environmental Management, Isabela State University, Garita, Cabagan, Isabela, Philippines

Article published on November 30, 2019

Key words: Philippine endemics, Ultrabasic forest, Species richness, Threatened species

Abstract This study provides information on the floral diversity, endemism and conservation status of the lowland ultrabasic forest in the Northern Sierra Madre Natural Park (NSMNP), Palanan, Isabela, Northeast Luzon, Philippines, which is vital to the management of the protected area. A total of 266 species in 140 genera and 71 families were recorded consisting of 12 herbs, 18 lianas, 66 shrubs, 169 trees and an endemic-epiphytic woody parasite. The most diverse among the genera with the highest number of taxa were Syzygium (32 spp.), Palaquium (12 spp.), Garcinia (9 spp.), Glochidion (9 spp.), and (5 spp.). Species richness was highest for family Myrtaceae (35 spp.) followed by Rubiaceae (23 spp.), Phyllanthaceae (17 spp.), Sapotaceae (16 spp.), and (14 spp.). Forty-two (42) of the total families were represented by a single genus. Species endemism was high with 40% (107 spp.) Philippine endemics: four (4) were found endemic only to Isabela Province - one of which was recorded endemic only to Sierra Madre Natural Park while 23 were endemic only to Luzon Island. Thirty-nine (39) species are globally threatened: six (6) being critically endangered, four (4) endangered, 22 vulnerable and seven (7) near threatened.

*Corresponding Author: Ma Visitacion D. Guingab  [email protected]

113 | Guingab J. Bio. & Env. Sci. 2019

Introduction Isabela Province, Luzon, Philippines (16º 56' N and The Sierra Madre Mountain Range dominates the 122 º26" E). It is characterized by flat to sloping near eastern pacific side of Northern Luzon, Philippines. riverbanks, gently sloping to rolling on the southern The Northern Sierra Madre Natural Park (NSMNP) portion and undulating on the eastern portion. About which lies within the Sierra Madre Biogeographic 5,390 ha are within the slope range of 3%-8%. Slope Zone is one of the country’s ten priority protected range of 8%-18% cover about 726 ha while at slope areas and the largest remaining tract of tropical range 0%-3% cover 490 ha. Clay soil type is the most rainforest with a total of 359,486 hectares. It consists prevalent. Other soil types identified in the area of seven forest vegetation types, the ultrabasic forest include loam, sandy, clay loam, sandy loam, and as one of the most diverse forest ecosystems and the sandy clay. Rainfall is more or less evenly distributed highest in terms of endemism. The reason for such throughout the year with mean annual rainfall of outstanding high biodiversity is that the country is 3,218 mm and annual totals ranging from 1,347 to fundamentally archipelagic in nature, each island 6,841 mm and all months exceeding 100 mm of rain. with diverse (but specific) geological origins and Mean annual temperature during summer was histories. Each of the geo-historically distinct sets of recorded at 29ºC and 18ºC during rainy season. islands is home to a unique set of species of flora and About 20 typhoons frequently come from the fauna. Declining temperatures and increasing rainfall northeast border with wind gusts up to 200 kph, in one particular mountainous area gives rise to which have significant effects on the forest through major types of rainforests. Layers of humus are thin direct crown damage. Major portion of the area and scattered in the lowland forest, but build into a (about 5,000 ha) is situated at 0-100 meters above blanket at higher elevations. sea level (masl) while the 1,606-hectare ultrabasic

forest is situated at range of 100-300masl (Fig. 1). The ultrabasic forest occurs in soil rich in heavy metals like silica, nickel, chromium, cobalt, iron and magnesium. It is generally characterized by sclerophyllous stunted vegetation. Unlike the other ultrabasic forests in the Philippines, NSMNP has a unique flora including its own Isabela endemic, Sierra Lowland ultrabasic forest Madre mangkono (Xanthostemon fruticosus Peter G. Wilson & Co) which is dominant in some parts of the ultrabasic forest. Other species include small trees, low- spreading to erect shrubs and several herbaceous (Co, 2006). An updated species list was provided based on field surveys from 1991 onwards and analysis of herbarium records. The study aimed to assess the Fig. 1. Location map of the study area in NSMNP, diversity of flora of NSMNP as basis for its conservation. Palanan, Isabela. Specifically it aimed to: a) describe the plant community composition of the lowland ultrabasic forest; b) Floristic Inventory determine the plant richness of taxa by family, genera Floristic inventory was conducted by repeated transect and species; c) determine plant endemism; and d) assess walks in the study area. Ten transect plots of 10 x 100 the conservation status of the species. m equivalent to 0.1 ha per plot were established. All plots were surveyed giving a total sample area of one Materials and methods ha. All woody plants (lianas, trees and shrubs) with Study Area girth at breast height (GBH) above 2.5 cm for trees and The study area is located within the Northern Sierra over one cm GBH for lianas within the plots were Madre Natural Park, southern part of Palanan, counted, numbered, pre-identified, photo-documented

114 | Guingab J. Bio. & Env. Sci. 2019 and taken for sample. Herbaceous plants were also pre- essential elements for many plants. But despite this identified and collected. Plant samples were harsh soil environment the flora is very rich with transported to the Isabela State University Herbarium endemic plants. (ISUH) for processing. Seventy - one (71) families consisting of 140 genera Collection, Processing and Identification of Specimens were recorded in the lowland ultrabasic forest. The Ten fertile samples and a minimum of three sterile species composition is an assemblage of 12 samples per species were collected and processed herbaceous terrestrial and epiphytic plants, 18 using the wet method. All samples were dried at the lianas/woody climbers, 66 shrubs, 169 trees and an Isabela State University at Cabagan Campus and endemic-epiphytic woody parasite. It is very deposited at the ISUH. Specimens were identified and interesting to note this remarkable total number of verified using various floral keys and comparison with 266 identified taxa despite the extreme herbarium specimens. Plants were classified by concentrations on heavy metal toxic to many plants families using the Angiosperm Phylogenetic Group and how the plants were able to tolerate such soil (APG) III classification scheme (Bremer et al. 2009). conditions (Table 1). Taxonomic studies on similar soil formations in the Philippines reveal the same Data Analysis species richness and diversity. Qualitative floristic measures of data were used to determine the species composition and level of plant Table 1. Species composition of lowland ultrabasic richness at species, genera and family levels. forest in the Northern Sierra Madre Natural Park. Importance value index for woody species was Legend: t=tree, s=shrub, l=liana, th=terrestrial herb, calculated by determining the relative frequency, eh=epiphytic herb, ewp=epiphytic woody parasite. Common relative density and relative basal area. Species Name Family Name Name & Habit

Adenanthera Fabaceae Tanglin (t) The global conservation status of the species was intermedia Merr. Adenanthera assessed based largely on the available data from the kostermansii Fabaceae Rawal (t) International Union for the Conservation of Nature I.C.Nielsen Agathis philippensis Araucariaeae Almaciga (t) (IUCN) Red List of Threatened Species (2017). Warb. Agelaea borneensis Locally threatened species were based from the Connaraceae Tayabak (l) (Hook.f.) Merr. National List of Threatened Philippine Plants issued Agrostistachys Haginis-agos Euphorbiaceae by the Department of Environment and Natural borneensis Becc. (s) Alchornea rugosa Euphorbiaceae Aguioi (s) Resources (DENR-DAO 2017-11). (Lour.) Müll.Arg. Alpinia brevilabris Shell ginger Zingiberaceae C.Presl (th) Results and discussion Alstonia spectabilis Apocynaceae Kahoi-dilau (t) Floristic composition R.Br. Alyxia monticola Apocynaceae Harupagot (l) The lowland ultrabasic forest of the NSMNP is C.B.Rob. Alyxia sibuyanensis probably one of the most diverse among forest types Apocynaceae Alyxia Elmer in the country. This forest type is interesting because Ampelocissus ochracea Ampelocissus Vitaceae of its exceptionally rich flora, its remarkable levels of (Teijsm. & Binn.) Merr. (l) Amyema acuta (Tiegh.) species and generic endemism. The vegetation is Danser Loranthaceae Amyena (ewp) sparse and plants are stunted. Trees and shrubs tend Anisoptera thurifera (Blanco) Blume Palosapis (t) to have thick, leathery leaves and sometimes reach to Antidesma macgregorii Bignai-gubat Phyllanthaceae only one or two meters tall. The soils are rich in toxic C.B.Rob. (t) minerals such as nickel, iron and magnesium but very Antidesma montanum Bignai-kintab Blume Phyllanthaceae poor in potassium, calcium and phosphorus which are (s)

115 | Guingab J. Bio. & Env. Sci. 2019

Common Common Species Name Family Name Species Name Family Name Name & Habit Name & Habit Antirhea caudata Dimupang- Canarium hirsutum Rubiaceae Milipili (t) (M.E.Jansen) Chaw buntotan (s) Willd. Antirhea ramosii Chaw Ramos Canarium luzonicum Piling-liitan Rubiaceae Burseraceae dimupa (s) (Blume) A.Gray (t) Antirhea tayabensis Tayabas Canthium monstrosum Tadiang- Rubiaceae Rubiaceae Chaw dimupa (s) (A.Rich.) Merr. anuang (t) Aporosa symplocifolia Canthium Phyllanthaceae Malabignai (t) Merr. trichophorum Quisumb.Rubiaceae Ambabasal (t) Aquilaria cumingiana & Merr. Thymelaeaceae Butlo (s) (Decne.) Ridl. Carallia brachiata Bakauan- Rhizophoraceae Arcangelisia flava (L.) (Lour.) Merr. gubat (t) Menispermaceae Abutra (l) Merr. Casearia fuliginosa Salicaceae Talitan (t) Archidendron clypearia (Blanco) Blanco Fabaceae Tiagkot (t) (Jack) I.C.Nielsen Cephalomanes HymenophyllaCephalomanes Archidendron obscurum (Blume) ceae (h) scutiferum (Blanco) Fabaceae Anagap (t) K.Iwats. I.C.Nielsen Champereia manillana Opiliaceae Garimo (t) Ardisia alverezii Merr. Alverez tagpo (Blume) Merr. Primulaceae (s) Cleistanthus everettii Everett Phyllanthaceae Ardisia darlingii Merr. Primulaceae Barasingag (s) C.B.Rob. anupag (t) Ardisia tomentosa Cleistanthus Primulaceae Mulang (s) Phyllanthaceae Anupag (s) C.Presl pedicellatus Hook.f. Artocarpus altilis Rimas/Antipol Croton leiophyllus Tagoang-uak Moraceae Euphorbiaceae (Parkinson) Fosberg o (t) Müll.Arg. (s) Artocarpus rubrovenius Croton luzoniensis Pagaibayong Moraceae Kalulot (t) Euphorbiaceae Warb. Müll.Arg. (s) Croton Atuna racemosa subsp. Tabon-tabon Quisumbing Chrysobalanaceae quisumbingianus Euphorbiaceae racemosa Raf. (t) tuba (s) Barringtonia Croizat Cyrtandra disparifolia macrostachya (Jack) Lecythidaceae Karakuat (t) Gesneriaceae Cyrtandra (s) Kurz Quisumb. Beilschmiedia Cyrtandra oblongata Lauraceae Tirukan (t) Gesneriaceae Cyrtandra (s) glomerata Merr. Merr. Beilschmiedia lucidula incurvata Lauraceae Bagaoring (t) Burseraceae Kamingi (t) (Miq.) Kosterm. (Engl.) H.J.Lam. Dacryodes rostrata Brackenridgea Burseraceae Lunai (t) fascicularis (Blanco) Ochnaceae Bitas (t) (Blume) H.J.Lam. Daemonorops mollis Fern.-Vill. Arecaceae Alimuran (l) Breynia cernua (Poir.) Kalamyasan (Blanco) Merr. Phyllanthaceae Daemonorops Mull.-Arg (s) Arecaceae Ditan (l) Breynia vitis-idaea Matang-hipon ochrolepis Becc. Phyllanthaceae Daphniphyllum Daphniphyllac (Burm.f.) C.E.C.Fisch. (s) Inutatan (t) Buchanania glaucescens Blume eae arborescens (Blume) Anacardiaceae Balinghasai (t) Dasymaschalon Blume clusiflorum (Merr.) Annonaceae Malaatis (s) Buchanania insignis Merr. Anacardiaceae Balihud (t) Blume Decaspermum Buxus rolfei S.Vidal fruticosum J.R.Forst. & Myrtaceae Patalsik (s) Buxaceae Malagaapi (s) G.Forst. blancoi Bitanghol (t) Dimocarpus longan Planch. & Triana subsp. malesianus Sapindaceae Alupag (t) Calophyllum soulattri Pamintaogon Calophyllaceae Leenh. Burm.f. (t) Dimorphocalyx Calophyllum whitfordii Calophyllaceae Pamitaogen (t) ixoroides (C.B.Rob.) Euphorbiaceae Agindulong (s) Merr. Airy Shaw Camellia lanceolata Dinochloa dielsiana Theaceae Haikan (s) Poaceae Bamboo (l) (Blume) Seem. Pilg. Cananga odorata Diospyros buxifolia Ebenaceae Gumunan (t) (Lam.) Hook.f. & Annonaceae Ilang-ilang (t) (Blume) Hiern Thomson Diospyros cauliflora Canarium euryphyllum Blume Ebenaceae Tamil (t) var. europhyllum Burseraceae Mayakiat (t) Diospyros discolor Perkins Ebenaceae Kamagong (t) Canarium gracile Engl. Pagsahingin- Willd. Burseraceae langgam (t) Diospyros nitida Merr. Ebenaceae Katilma (t)

116 | Guingab J. Bio. & Env. Sci. 2019

Common Common Species Name Family Name Species Name Family Name Name & Habit Name & Habit Diplospora Glochidion rubrum Bagnang-pula Kaping- Phyllanthaceae fasciculiflora (Elmer) Rubiaceae Blume (s) bundok (s) Elmer Glochidion subfalcatum Bagnang- Discocalyx var. nitidum (Merr.) Phyllanthaceae gubat (t) cybianthoides (A.DC.) Primulaceae Paginga (t) Chakrab. & M.Gangop. Mez Glochidion triandrum Phyllanthaceae Bagna (t) Dracaena multiflora (Blanco) C.B.Rob. Asparagaceae Dracaena (h) Warb.ex Sarasin Glochidion Phyllanthaceae Halakan (t) Elaeocarpus argenteus urophylloides Elmer Elaeocarpaceae Bakani (t) Merr. Glochidion williamsii Phyllanthaceae Tumuhan (t) Elaeocarpus cumingii C.B.Rob. Elaeocarpaceae Hunggo (t) Turcz. Gnetum gnemon L. Gnetaceae Bago (t) Elaeocarpus ilocanus Gnetum latifolium Lamparahan Elaeocarpaceae Panulauen (t) Gnetaceae Merr. Blume (l) Elaeocarpus monocera Elaeocarpaceae Gomphandra coi Schori Co marumai Tabian (t) Stemonuraceae Cav. (t) Ellipanthus tomentosus Luzon Gomphia serrata Connaraceae Ochnaceae Salaktok (t) Kurz alomangoi (t) (Gaertn.) Kanis Endocomia macrocoma Goniothalamus elmeri Annonaceae Bigus (t) subsp. macrocoma Myristicaceae Kumpang (t) Merr. (Miq.) W.J.de Wilde Gonocaryum Falcatifolium gruezoi Cardiopterida Taingang- calleryanum (Baill.) Binaton (t) ceae babui (t) de Laub. Becc. Ficus fistulosa Reinw. Gonystylus Moraceae Kamahiuan (t) Lanutan- ex Blume macrophyllus (Miq.) Thymelaeaceae bagyo (t) Ficus punctata Thunb. Moraceae Is-is maya (l) Airy Shaw Ficus rivularis Merr. Baleteng-bato Greeniopsis discolor Pangalimanan Moraceae Rubiaceae (s) Merr. (s) Ficus ruficaulis Merr. Moraceae Tabgun (t) Greeniopsis multiflora Rubiaceae Paluai (s) Flagellaria indica L. Flagellariaceae Whip vine (l) (Elmer) Merr. Garcinia brevirostris Greeniopsis pubescens Paluai-mabolo Clusiaceae Basan (t) Rubiaceae Scheff. Merr. (s) Guioa bicolor Merr. Garcinia celebica L. Clusiaceae Bunog (t) Sapindaceae Kaningning (t) Garcinia dulcis (Roxb.) Taklang-anak Guioa koelreuteria Clusiaceae Sapindaceae Alahan (t) Kurz (t) (Blanco) Merr. Garcinia lateriflora Guioa pleuropteris Clusiaceae Kandis (t) Sapindaceae Bunsikag (t) Blume (Blume) Radlk. Garcinia luzoniensis Malabinukau Gymnacranthera Clusiaceae farquhariana var. Merr. (t) Myristicaceae Anuping (t) Garcinia macgregorii paniculata (A.DC.) Clusiaceae Tagkon (t) Merr. R.T.A.Schouten Gymnostoma Garcinia oligophlebia Ahoho del Clusiaceae Dilis (t) rumphianum (Miq.) Casuarinaceae Merr. Monte (t) Garcinia rubra Merr. L.A.S.Johnson Clusiaceae Kamandiis (t) Gynochthodes Gynochthodes Garcinia venulosa philippinensis (Elmer) Rubiaceae Clusiaceae Gatasan (t) (l) (Blanco) Choisy Merr. Gardenia elata var. Helicia robusta (Roxb.) Salimai- Proteaceae longipedicellata Rubiaceae Balanigan (s) R.Br. ex Blume lakihan (t) K.M.Wong Heterospathe Gardenia merrillii Arecaceae Bilisan (t) Rubiaceae Bagaoi (s) brevicaulis Fernando Elmer Heterospathe Cagayan Geniostoma rupestre Arecaceae Loganiaceae Gagadang (s) cagayanensis Becc. bilisan (t) J.R.Forst. & G.Forst. Homalium panayanum Ampupuyot Gironniera subaequalis Salicaceae Cannabaceae Ngahil (t) Fern.-Vill. (s) Planch. Homonoia riparia Euphorbiacea Glochidion lutescens Mangapos (s) Phyllanthaceae Salanisin (t) Lour. e Blume Horsfieldia ardisiifolia Myristicaceae Tapol (t) Glochidion luzonense (A.DC.) Warb. Phyllanthaceae Apaped (s) Elmer Horsfieldia costulata Dugo-dugoan (Miq.) Warb. Myristicaceae Glochidion philippicum (t) Phyllanthaceae Iba-ibaan (t) (Cav.) C.B.Rob. Horsfieldia Glochidion pubicapsa polyspherula (Hook.f. Myristicaceae Dara-dara (t) Phyllanthaceae Kainag (s) Airy Shaw ex King) J.Sinclair

117 | Guingab J. Bio. & Env. Sci. 2019

Common Common Species Name Family Name Species Name Family Name Name & Habit Name & Habit Hoya imbricata Decne. Apocynaceae Hoya (eh) tenuipetiolatum Merr. Intsia bijuga (Colebr.) Paracroton pendulus Fabaceae Ipil (t) Euphorbiaceae Panantolen (t) Kuntze (Hassk.) Miq. Intsia palembanica Palawan ipil Paraderris luzoniensis Fabaceae Fabaceae Paraderis (l) Miq. (t) Adema Ixora crassifolia Merr. Mangopong Pavetta indica L. Rubiaceae Rubiaceae Gusokan (s) (s) Phryium fasciculatum Kibatalia blancoi (Rolfe Marantaceae Phryium (h) Apocynaceae Pasnit (t) (C.Presl) Horan. ex Stapf) Merr. Phyllanthus tenuipes Phyllanthus Knema glomerata Phyllanthaceae Myristicaceae Tambalau (t) C.B.Rob. (s) Merr. Pinanga isabelensis Knema kunstleri (King) Tambalau- Arecaceae Takon (t) Myristicaceae Becc. Warb. kapalan (t) Pinanga maculata Mottled- leaf Knema ridsdaleana Ridsdale Arecaceae Myristicaceae Porte ex Lem. pinanga (t) W.J.de Wilde tambalau (t) Piper lessertianum Malapaminta Piperaceae Knema stellata Merr. Myristicaceae Durugo (t) (Miq.) C.DC. (l) Lagerstroemia Planchonella firma Sapotaceae Bagomaho (t) paniculata (Turcz.) Lythraceae Talulong (t) (Miq.) Dubard S.Vidal Planchonella obovata Sapotaceae Mangkas (t) Licania splendens Chrysobalanac (R.Br.) Pierre Buku-buku (t) (Korth.) Prance eae neriifolius Mala-adelfa Podocarpaceae Lithocarpus robinsonii D.Don (t) Fagaceae Babaisakan (t) Rehder Podocarpus Dilang-butiki Lithocarpus sulitii polystachyus R.Br. ex Podocarpaceae Fagaceae Pangnan (t) (t) Soepadmo Endl. Lophopetalum Podocarpus rumphii Malakauayan Celastraceae Aras (t) Podocarpaceae beccarianum Pierre Blume (t) Lygodium merrillii Podochilus plumosus Podochilus Lygodiaceae fern (th) Orchidaceae Copel. Ames (eh) Maasia glauca (Hassk.) Pothoidium lobbianum Pothoidium Annonaceae Dogan (s) Araceae Mols, Kessler & Rogstad Schott (eh) Madhuca betis (Blanco) Pothos inequilaterus Sapotaceae Betis (t) Araceae Pothos (eh) J.F.Macbr. (C.Presl) Engl. Magnolia liliifera (L.) Pothos scandens L. Magnoliaceae Patangis (t) Araceae Pothos (eh) Baill. Pouteria macrantha Myristica colinridsdalei Ridsdale Sapotaceae White nato (t) Myristicaceae (Merr.) Baehni W.J.de Wilde duguan (t) Prismatomeris Oldenlandia prostrata Oldenlandia Rubiaceae Malahagpo (s) Rubiaceae brachypus Ridl. (Blume) Kuntze (th) Prismatomeris Palaquium bataanense Bataan tagatoi Sapotaceae tetrandra (Roxb.) Rubiaceae Hagpo (s) Merr. (t) K.Schum. Palaquium Alakaak-tilos Prunus grisea (Blume) Sapotaceae Rosaceae Lago (t) elliptilimbum Merr. (t) Kalkman Palaquium elongatum Alakaak-haba Psychotria nitens Sapotaceae Rubiaceae Psychotria (s) Merr. (t) (Merr.) Merr. Palaquium Psychotria pilosella Sapotaceae Alakaak (t) Rubiaceae Pasnoban (s) gigantifolium Merr. Elmer Palaquium globosum Pycnarrhena tumefacta Pycnarrhena Sapotaceae Arabon (t) Menispermaceae H.J.Lam Miers. (l) Palaquium lanceolatum Quassia indica Sapotaceae Palak-palak (t) Simaroubaceae Manungal (s) Blanco (Gaertn.) Noot. Palaquium luzoniense Radermachera coriacea Labayanana Sapotaceae Nato (t) Bignoniaceae (Fern.-Vill.) S.Vidal Merr. (t) Palaquium merrillii Radermachera Sapotaceae Dulitan (t) Bignoniaceae Sayo (t) Dubard gigantea (Blume) Miq. Palaquium philippense Malak-malak Radermachera pinnata Banai-banai Sapotaceae Bignoniaceae (Perr.) C.B.Rob. (t) (Blanco) Seem. (t) Palaquium Isabela nato Rhaphiolepis pseudocuneatum Sapotaceae (t) philippinensis (S.Vidal) Rosaceae Marabarani (t) H.J.Lam Kalkman Palaquium Sorsogon nato Rinorea bengalensis sorsogonense Elmer ex Sapotaceae Violaceae Tuak (s) (t) (Wall.) Gagnep. H.J.Lam. Rourea minor (Gaertn.) Connaraceae Kamagsa (l) Palaquium Sapotaceae Maniknik (t) Alston

118 | Guingab J. Bio. & Env. Sci. 2019

Common Common Species Name Family Name Species Name Family Name Name & Habit Name & Habit Salacia chinensis L. Matang-ulang Syzygium Celastraceae (l) phanerophlebium Myrtaceae Malayambu (t) Semecarpus (C.B.Rob.) Merr. Anacardiaceae Ligas-laki (t) macrophyllus Merr. Syzygium philippinense Myrtaceae Bagohian (t) Severinia disticha (C.B.Rob.) Merr. Rutaceae Malarayap (s) (Blanco) Swingle Syzygium Shorea polysperma Dipterocarpac polycephaloides Myrtaceae Lipote (t) Tangile (t) (Blanco) Merr. eae (C.B.Rob.) Merr. Strychnos minor Mulawin- Syzygium ramosii Magtalulong Loganiaceae Myrtaceae Dennst. baging (l) (C.B.Rob.) Merr. (t) Suregada glomerulata Syzygium robertii Euphorbiaceae Malaua (t) Myrtaceae Kiyugkug (t) (Blume) Baill. (Merr.) Merr. Swintonia acuta Engl. Syzygium Anacardiaceae Kaluis (t) Kalogkog- subrotundifolium Myrtaceae Syzygium antisepticum dagat (s) (Blume) Merr. & Myrtaceae Marlig (t) (C.B.Rob.) Merr. Syzygium tripinnatum L.M.Perry Myrtaceae Hagis (s) Syzygium (Blanco) Merr. Syzygium arcuatinervium (Merr.) Myrtaceae Birakbak (t) Malatampui- xanthophyllum Myrtaceae Craven & Biffin haba (s) Syzygium bataanense Bataan (C.B.Rob.) Merr. Myrtaceae Tabernaemontana (Merr.) Merr. malaruhat (t) Apocynaceae Pandakaki (s) Syzygium bernardoi Maramaatam pandacaqui Lam. Myrtaceae Taenitis blechnoides (Merr.) Merr. (t) Pteridaceae Taenitis (th) Syzygium bordenii Malaruhat- (Willd.) Sw. Myrtaceae Tapeinidium (Merr.) Merr. puti (t) Tapeinidium Syzygium brachyurum Tonau-pugot acuminatum Lindsaeaceae Myrtaceae (th) Merr. (s) K.U.Kramer Teijsmanniodendron Syzygium calubcob Sasalit/Dangu Myrtaceae Kalubkob (s) ahernianum (Merr.) Lamiaceae (C.B.Rob.) Merr. la (t) Syzygium Bakh. Terminalia citrina ciliatosetosum (Merr.) Myrtaceae Lakangan (t) Combretaceae Bingas (t) Merr. Roxb. ex Fleming Syzygium crassipes Terminalia darlingii Myrtaceae Barukbak (s) Combretaceae Malaputat (t) (C.B.Rob.) Merr. Merr. Syzygium curranii Curran lipote Terminalia edulis Myrtaceae Combretaceae Kalumpit (t) (C.B.Rob.) Merr. (t) Blanco Syzygium densinervium Terminalia foetidissima Talisai-gubat Myrtaceae Salakadan (s) Combretaceae (Merr.) Merr. Griff. (t) Syzygium everettii Ternstroemia Pentaphylacac Myrtaceae Malahagnit (s) Apin (t) (C.B.Rob.) Merr. gitingensis Elmer eae Ternstroemia Pentaphylacac Syzygium fastigiatum Arana (t) (Blume) Merr. & Myrtaceae Hahanum (s) philippinensis Merr. eae Timonius arboreus Hambabayud L.M.Perry Rubiaceae Syzygium grande Midbit- Elmer (s) Myrtaceae Timonius oligophlebius Upong-ilanan (Wight) Walp. laparan (t) Rubiaceae Syzygium intumescens Merr. (s) Myrtaceae Hagoho (t) Timonius quinqueflorus (C.B.Rob.) Merr. Rubiaceae Malabalod (s) Syzygium isabelense Merr. Myrtaceae Gubal (t) Tinospora glabra (Quisumb.) Merr. Menispermaceae Baging (l) Syzygium longissimum (Burm.f.) Merr. Myrtaceae Tual (t) Trigonachras acuta (Merr.) Merr. Sapindaceae Darunga (t) Syzygium longistylum (Hiern) Radlk. Myrtaceae Lobagan (t) Trigonostemon (Merr.) Merr. Trigonostemo Syzygium luzonense aurantiacus (Kurz ex Euphorbiaceae Myrtaceae Duktulan (t) n (t) (Merr.) Merr. Teijsm. & Binn.) Boerl. Syzygium mainitense Trigonostemon Katap- Myrtaceae Malabikuas (t) Euphorbiaceae (Elmer) Merr. filiformis Quisumb. himaymay (s) Syzygium mananquil Trigonostemon hirsutus Malakokonon Myrtaceae Manangkil (t) Euphorbiaceae (Blanco) Merr. C.B.Rob. (s) Syzygium nervosum Myrtaceae Malaruhat (t) Trigonostemon A.Cunn. ex DC. longipedunculatus Euphorbiaceae Kulis (s) Syzygium nitidum Myrtaceae Makaasim (t) (Elmer) Elmer Benth. Syzygium pallidum Trigonostemon Myrtaceae Kauag (t) Euphorbiaceae Katap (t) Merr. longipes (Merr.) Merr.

119 | Guingab J. Bio. & Env. Sci. 2019

Common elsewhere in the region to compare ultrabasic forest Species Name Family Name Name & Habit diversity and this could provide valuable basic Tristaniopsis oblongifolia (Merr.) Tigang-haba information on the different life forms and species of Myrtaceae Peter G.Wilson & (t) this forest type. Waterh. Vatica mangachapoi Dipterocarpac Narig (t) Blanco eae Endemism and Conservation Status Vavaea amicorum Nangka- Meliaceae Benth. nangka (t) Endemism in the lowland ultrabasic forest was high Villaria fasciculiflora Rubiaceae Otto (t) in NSMNP. Of its total species composition, 107 taxa Quisumb. & Merr. Xanthophyllum (40%) were endemic to the Philippines, four (4) of Polygalaceae Durog (s) bracteatum Chodat which were found endemic only to Isabela Province Xanthophyllum discolor Polygalaceae Kabot (t) Chodat while 23 were endemic only to Luzon Island (Table Xanthostemon Sierra Madre 2). Isabela endemics include Canthium trichophorum fruticosus Peter Myrtaceae mangkono (s) G.Wilson & Co Quisumb. & Merr. (Rubiaceae), Cyrtandra Xylopia dehiscens Annonaceae Sudkad (t) disparifolia Quisumb. (Gesneriaceae), Pinanga (Blanco) Merr. Xylopia densifolia Tangisang- isabelensis Becc. (Arecaceae) and Xanthostemon Annonaceae Elmer bagyo (t) fruticosus Peter G.Wilson & Co (Myrtaceae).

Xanthostemon fruticosus, the Sierra Madre Diversity Mangkono was recorded only from the Sierra Madre Among the 71 families encountered, almost all were Mountain Range. Most of the endemic species were represented by angiosperms with only three (3) represented by families Myrtaceae (21), Rubiaceae gymnosperms such as Araucariaceae, Gnetaceae and (15), Sapotaceae (10), Myristicaceae (7), Podocarpaceae. The angiosperm families having the Euphorbiaceae (7), Arecaceae (6), Phyllanthaceae (5) most number of genera is Rubiaceae (13) followed by and Annonaceae (4). Euphorbiaceae (8) and Phyllanthaceae (6). Floristic study in tropical dry forests in the Pacific and other Table 2. Endemic taxa in the lowland ultrabasic tropical dry forests sites of the world (Gillespie et al., forest of the Northern Sierra Madre Natural Park. 2000; Gillespie et al., 2011; Genry, 1995) reveals similar Species floristic composition with Rubiaceae, Euphorbiaceae 1. Alyxia monticola Other Philippine and Myrtaceae as the most speciose angiosperm C.B.Rob. endemic 2. Ampelocissus ochracea Other Philippine families. The most diverse among the genera with the (Teijsm. & Binn.) Merr. endemic highest number of taxa was Syzygium of the family 3. Amyema acuta (Tiegh.) Other Philippine Danser endemic Myrtaceae with 32 species. Other speciose genera were 4. Antirhea caudata Other Philippine Palaquium (12 spp.), Garcinia (9 spp.), Glochidion (9 (M.E.Jansen) Chaw endemic 5. Antirhea ramosii Chaw Luzon endemic spp.), and Trigonostemon (5 spp.). 6. Antirhea tayabensis Luzon endemic Chaw 7. Aporosa symplocifolia Other Philippine In terms of species richness, the highest number of Merr. endemic taxa was represented by family Myrtaceae with 35 8. Archidendron scutiferum Other Philippine (Blanco) I.C.Nielsen endemic species followed by Rubiaceae (23 spp.), Other Philippine 9. Ardisia alverezii Merr. Phyllanthaceae (17 spp.), Sapotaceae (16 spp.), and endemic 10. Ardisia darlingii Merr. Luzon endemic Euphorbiaceae (14 spp.). Forty-two (42) of the 11. Artocarpus rubrovenius Luzon endemic families (59%) were represented by a single genus. Warb. 12. Brackenridgea Other Philippine fascicularis (Blanco) endemic One hundred and twenty-five (125) species or 52 Fern.-Vill. Other Philippine percent of the total number of taxa recorded in this 13. Buxus rolfei S.Vidal endemic forest type were specialists, 24 of which are 14. Calophyllum whitfordii Other Philippine threatened species. There was no available data Merr. endemic

120 | Guingab J. Bio. & Env. Sci. 2019

Species Species 15. Canarium euryphyllum Other Philippine 45. Heterospathe brevicaulis Luzon endemic var. europhyllum Perkins endemic Fernando 16. Canarium luzonicum Other Philippine 46. Heterospathe Luzon endemic (Blume) A.Gray endemic cagayanensis Becc. 17. Canthium trichophorum 47. Horsfieldia costulata Other Philippine Isabela endemic Quisumb. & Merr. (Miq.) Warb. endemic 18. Casearia fuliginosa Other Philippine Other Philippine 48. Ixora crassifolia Merr. (Blanco) Blanco endemic endemic 19. Croton leiophyllus Other Philippine 49. Kibatalia blancoi (Rolfe Other Philippine Müll.Arg. endemic ex Stapf) Merr. endemic 20. Croton luzoniensis Other Philippine Luzon endemic 50. Knema glomerata Merr. Müll.Arg. endemic 21. Croton quisumbingianus Other Philippine 51. Knema kunstleri (King) Other Philippine Croizat endemic Warb. endemic 22. Cyrtandra disparifolia 52. Knema ridsdaleana Other Philippine Isabela endemic Quisumb. W.J.de Wilde endemic 23. Cyrtandra oblongata Other Philippine Luzon endemic 53. Knema stellata Merr. Merr. endemic 24. Daemonorops mollis Other Philippine 54. Lagerstroemia (Blanco) Merr. endemic paniculata (Turcz.) Luzon endemic 25. Daemonorops ochrolepis Other Philippine S.Vidal Becc. endemic 55. Lithocarpus robinsonii Other Philippine 26. Dasymaschalon Other Philippine Rehder endemic clusiflorum (Merr.) Merr. endemic 56. Lithocarpus sulitii Other Philippine 27. Dimorphocalyx ixoroides Other Philippine Soepadmo endemic (C.B.Rob.) Airy Shaw endemic 57. Myristica colinridsdalei Other Philippine Other Philippine W.J.de Wilde endemic 28. Dinochloa dielsiana Pilg. endemic 58. Palaquium bataanense Other Philippine Other Philippine Merr. endemic 29. Diospyros nitida Merr. endemic 59. Palaquium elliptilimbum Other Philippine 30. Diplospora fasciculiflora Other Philippine Merr. endemic (Elmer) Elmer endemic 60. Palaquium elongatum Luzon endemic 31. Elaeocarpus argenteus Other Philippine Merr. Merr. endemic 61. Palaquium gigantifolium Other Philippine 32. Elaeocarpus ilocanus Other Philippine Merr. endemic Merr. endemic 62. Palaquium globosum Luzon endemic 33. Elaeocarpus monocera Other Philippine H.J.Lam Cav. endemic 63. Palaquium lanceolatum Luzon endemic 34. Gardenia elata var. Blanco longipedicellata Luzon endemic 64. Palaquium merrillii Other Philippine K.M.Wong Dubard endemic 35. Glochidion subfalcatum 65. Palaquium philippense Other Philippine Other Philippine var. nitidum (Merr.) (Perr.) C.B.Rob. endemic endemic Chakrab. & M.Gangop. 66. Palaquium sorsogonense Other Philippine 36. Glochidion triandrum Other Philippine Elmer ex H.J.Lam. endemic (Blanco) C.B.Rob. endemic 67. Palaquium Luzon endemic 37. Glochidion urophylloides Other Philippine tenuipetiolatum Merr. Elmer endemic 68. Phyllanthus tenuipes Other Philippine 38. Goniothalamus elmeri Other Philippine C.B.Rob. endemic Merr. endemic 69. Pinanga isabelensis Isabela endemic 39. Greeniopsis discolor Becc. Luzon endemic Merr. 70. Pinanga maculata Porte Other Philippine 40. Greeniopsis multiflora Other Philippine ex Lem. endemic (Elmer) Merr. endemic 71. Podochilus plumosus Other Philippine 41. Greeniopsis pubescens Ames endemic Luzon endemic Merr. 72. Pothos inequilaterus Other Philippine (C.Presl) Engl. endemic Other Philippine 42. Guioa bicolor Merr. 73. Psychotria nitens (Merr.) Other Philippine endemic Merr. endemic 43. Gymnacranthera 74. Psychotria pilosella Other Philippine farquhariana var. Other Philippine Elmer endemic paniculata (A.DC.) endemic 75. Shorea polysperma Other Philippine R.T.A.Schouten (Blanco) Merr. endemic 44. Gynochthodes 76. Syzygium Other Philippine Other Philippine philippinensis (Elmer) arcuatinervium (Merr.) endemic endemic Merr. Craven & Biffin

121 | Guingab J. Bio. & Env. Sci. 2019

Species Assessment of the conservation status of taxa in the 77. Syzygium bataanense Other Philippine protected area is crucial in promoting the (Merr.) Merr. endemic 78. Syzygium bernardoi Other Philippine conservation of threatened species and provides the (Merr.) Merr. endemic foundation for making decisions regarding conserving 79. Syzygium bordenii Other Philippine (Merr.) Merr. endemic biodiversity from local to global levels. Table 3 shows 80. Syzygium brachyurum Other Philippine the status of the plant species where six (6) are Merr. endemic 81. Syzygium ciliatosetosum Other Philippine critically endangered as follows: Pangalimanan (Merr.) Merr. endemic (Greeniopsis discolor Merr.); Ridsdale duguan 82. Syzygium crassipes Other Philippine (C.B.Rob.) Merr. endemic (Myristica colinridsdalei W.J.de Wilde); Ridsdale 83. Syzygium curranii Other Philippine tambalau (Knema ridsdaleana W.J.de Wilde); (C.B.Rob.) Merr. endemic 84. Syzygium everettii Other Philippine Paluai-mabolo (Greeniopsis pubescens Merr.); Otto (C.B.Rob.) Merr. endemic (Villaria fasciculiflora Quisumb. & Merr.); and Sierra 85. Syzygium luzonense Other Philippine (Merr.) Merr. endemic Madre mangkono (Xanthostemon fruticosus Peter 86. Syzygium mainitense Other Philippine G.Wilson & Co). On the other hand, four (4) are (Elmer) Merr. endemic 87. Syzygium mananquil Other Philippine endangered species as follows: Heterospathe (Blanco) Merr. endemic brevicaulis Fernando, Madhuca betis (Blanco) 88. Syzygium pallidum Other Philippine Merr. endemic J.F.Macbr., Gomphandra coi Schori and Terminalia 89. Syzygium Other Philippine darlingii Merr. phanerophlebium endemic (C.B.Rob.) Merr. 90. Syzygium philippinense Other Philippine Table 3. Conservation status of plants in NSMNP’s (C.B.Rob.) Merr. endemic 91. Syzygium ramosii lowland ultrabasic forest. Luzon endemic (C.B.Rob.) Merr. Conservation 92. Syzygium robertii Other Philippine Species status (Merr.) Merr. endemic Agathis philippensis Warb. Vulnerable 93. Syzygium Other Philippine Anisoptera thurifera Vulnerable subrotundifolium endemic (Blanco) Blume (C.B.Rob.) Merr. Aquilaria cumingiana Vulnerable Syzygium xanthophyllum Other Philippine 94. (Decne.) Ridl. (C.B.Rob.) Merr. endemic Canarium luzonicum Vulnerable 95. Terminalia darlingii Luzon endemic (Blume) A.Gray Merr. Dimocarpus longan subsp. Near threatened 96. Timonius oligophlebius Luzon endemic malesianus Leenh. Merr. Diospyros cauliflora Blume Vulnerable 97. Timonius quinqueflorus Luzon endemic Diospyros discolor Willd. Vulnerable Merr. Falcatifolium gruezoi de Near threatened 98. Trigonostemon filiformis Other Philippine Laub. Quisumb. endemic Gardenia elata var. Vulnerable 99. Trigonostemon hirsutus Other Philippine longipedicellata K.M.Wong C.B.Rob. endemic Gomphandra coi Schori Endangered 100. Trigonostemon longipes Luzon endemic Gonystylus macrophyllus Vulnerable (Merr.) Merr. (Miq.) Airy Shaw 101. Tristaniopsis oblongifolia (Merr.) Peter G.Wilson & Luzon endemic Greeniopsis discolor Merr. Critically Waterh. endangered 102. Villaria fasciculiflora Greeniopsis pubescens Merr. Critically Luzon endemic Quisumb. & Merr. endangered Guioa bicolor Merr. Vulnerable 103. Xanthophyllum Other Philippine Heterospathe brevicaulis Endangered bracteatum Chodat endemic Fernando 104. Xanthophyllum discolor Other Philippine Heterospathe cagayanensis Near threatened Chodat endemic Becc. 105. Xanthostemon fruticosus Horsfieldia ardisiifolia Vulnerable Isabela endemic Peter G.Wilson & Co (A.DC.) Warb. Intsia bijuga (Colebr.) Vulnerable

106. Xylopia dehiscens Other Philippine Kuntze (Blanco) Merr. endemic Intsia palembanica Miq. Vulnerable Other Philippine 107. Xylopia densifolia Elmer Knema ridsdaleana W.J.de Critically endemic Wilde endangered

122 | Guingab J. Bio. & Env. Sci. 2019

Conservation wildlife hunting, forest fire due to slash-and-burn Species status farming, migration, and infrastructure development. Knema stellata Merr. Vulnerable Madhuca betis (Blanco) Endangered The information provided herein is extremely useful J.F.Macbr. to strengthen biodiversity conservation and Myristica colinridsdalei Critically W.J.de Wilde endangered sustainable use of biological resources in the area. Palaquium luzoniense Vulnerable Moreover, it provides a basis for the present botanical (Fern.-Vill.) S.Vidal Palaquium philippense Vulnerable knowledge which underpins further studies of the (Perr.) C.B.Rob. ecology and botany of the region. Pinanga isabelensis Becc. Near threatened Pinanga maculata Porte ex Near threatened Lem. References Podocarpus polystachyus Vulnerable R.Br. ex Endl. Bremer B, Bremer K, Chase MW, Fay MF, Podocarpus rumphii Blume Vulnerable Reveal JL, Soltis DE, Soltis PS, Stevens PF. Prunus grisea (Blume) Vulnerable Kalkman 2009. An update of the angiosperm phylogeny group Psychotria nitens (Merr.) Near threatened classification for the orders and families of flowering Merr. Psychotria pilosella Elmer Near threatened plants: APG III. Botanical Journal of Linnaean Radermachera coriacea Vulnerable Merr. Society 161, 105-121. Shorea polysperma (Blanco) Vulnerable Merr. Syzygium nitidum Benth. Vulnerable Co LL, LaFrankie JV, Lagunzad DA, Pasion Terminalia darlingii Merr. Endangered KAC, Consunji HT, Bartolome NA, Yap SL, Vatica mangachapoi Blanco Vulnerable Villaria fasciculiflora Critically Molina JE, Tongco MDC, Ferreras UF, Davies Quisumb. & Merr. endangered SJ, Ashton PS. 2006. Forest Trees of Palanan, Xanthostemon fruticosus Critically Peter G.Wilson & Co endangered Philippines: A Study in Population Ecology. Center for Tropical Forest Science. Other threatened species categorized as vulnerable

(22 species) and near threatened (8 species) include DENR Administrative Order. 2017. Updated Almaciga (Agathis philippensis Warb.); Kaningning National List of Threatened Philippine Plants and (Guioa bicolor Merr.); Tapol (Horsfieldia ardisiifolia their Categories. DAO 2017-11 (A.DC.) Warb.); Palawan-ipil (Intsia palembanica

Miq.); Durugo (Knema stellata Merr.); Nato Department of Environment and Natural (Palaquium luzoniense (Fern.-Vill.) S.Vidal); Dilang- Resources. 2006. Northern Sierra Madre Natural butiki (Podocarpus polystachyus R.Br. ex Endl.); Park and outlying areas inclusive of the buffer zone. Malakauayan (Podocarpus rumphii Blume); Lago UNESCO World Heritage Centre (Prunus grisea (Blume) Kalkman); Labayanana

(Radermachera coriacea Merr.); Lobagan (Syzygium Fernando ES. 1998. Vegetation of the Philippine longistylum (Merr.) Merr.); Tigang-haba (Tristaniopsis oblongifolia (Merr.) Peter G.Wilson & Islands. UPLB College, Laguna. Waterh.); Lunai (Dacryodes rostrata (Blume) H.J.Lam.); Ditan (Daemonorops ochrolepis Becc.); Fortus JR, Garcia HG. 2002. Floristic study of Agoho del Monte (Gymnostoma rumphianum (Miq.) ultrabasic forest in Northern Sierra Madre Natural Park. L.A.S.Johnson); and Bataan tagatoi (Palaquium Technical Report of NSMNP Conservation Project. bataanense Merr.). All the above species are heavy metal indicators of the ultrabasic forest. Gentry AH. 1995. Diversity and floristic composition of Neotopical dry forests in S.H. Bullock, H.A. Mooney and Threats to NSMNP biodiversity are attributed mainly E. Medina, eds. Seasonally dry tropical forests. to anthropogenic activities such as illegal logging, Cambridge University Press, Cambridge.

123 | Guingab J. Bio. & Env. Sci. 2019

Gillespie TW, Grijalva A, Farris CN. Lu XT, Yin JX, Tang JW. 2010. Structure, tree 2000. Diversity, Composition, and Structure of species diversity and composition of tropical seasonal Tropical Dry Forests in Central America. Plant rainforest in Xishuangbanna South-West China. Ecology 147, 37-47. Kluwer Academic Publishers. Journal of Tropical Forest Science 22(3), 260-270

Gillespie TW, Keppel G, Pau S, Price JP, Jaffré Naidu MT, Kumar OA. 2016. Tree diversity, stand T, Meyer JY, O'Neill K. 2011. Floristic structure, and community composition of tropical Composition and Natural History Characteristics of forests in Eastern Ghats of Andhra Pradesh, . Dry Forests in the Pacific University of Hawai'i Press Journal of Asia-Pacific Biodiversity Vol. 9, Issue 3, pp. 328-334. Guingab MaVD, Welzen PCvan. 2018. Woody Flora of the Northern Sierra Madre Natural Park and Zhu H, Yong C, Zhou S, Wang H, Yan L. 2015. Vicinity, Luzon, Philippines. ISU Publishing, Prints Vegetation, floristic composition and species diversity and Solutions. in a tropical mountain reserve in southern Yunnan, SW China with implications for conservation. International Union for Conservation of Tropical Conservation Science. Nature (IUCN). 2017. The IUCN Red List of Threatened Species . Downloaded on 19 March 2018.

124 | Guingab