Volume 16 Issue 1 - 2022 | 62
© Assocation of Systematic Biologists in the Philippines
SHORT COMMUNICATION | Philippine Journal of Systematic Biology DOI
Abstract
Recent biodiversity inventory efforts in the Anonang-Lobi mountain range in Leyte resulted in an additional distribution record for Utricularia striatula Sm. (Lentibulariaceae) in the Philippines. An updated distributional map of this species and notes on its habitat and ecology in the Philippines are provided in this paper.
Keywords: bladderworts, Burauen, carnivorous plant, lithophytic, phytogeography
Tristan Luap P. Senarillos
1*, Noe P. Mendez
2, Guiller Opiso
1& Jayson C. Ibañez
1,3Utricularia striatula (Lentibulariaceae), a New Distribution Record from Leyte Island, Philippines
SHORT COMMUNICATION | Philippine Journal of Systematic Biology DOI 10.26757/pjsb2022a16011
Introduction
Members of the genus Utricularia L. are commonly called bladderworts (Verma et al. 2014) and grouped within the family Lentibulariaceae. These plants are carnivorous with minute suction traps that are either submerged or underground (Taylor 1989). Species of the genus are found in a wide variety of wet habitats all over the world (Juniper et al. 1989; Cook 1996; Lansdown et al. 2013). In the Philippines, Utricularia is one of the three carnivorous plant genera and is represented by nine species which are all native to the country (Pelser et al. 2011 onwards).
During the rapid biodiversity assessment done by the Philippine Eagle Foundation (PEF) in Barangay Kagbana, Burauen, Leyte on 30 March 2021, a remote population of Utricularia striatula Sm. was found along the natural dike of the Marabong River. This biodiversity survey searched for the IUCN “Critically Endangered” Philippine Eagle (Pithecophaga jefferyi Ogilvie-Grant) (Birdlife International 2016), and to assess the habitat status and abundance of prey species within the Anonang-Lobi mountain range (PH077), which has been identified as one of the Key Biodiversity Areas (KBAs) in the Philippines (Mallari et al. 2001). The mountain range includes Mt Lobi, Mt Burauen Graben, and Mt Camaiyak, covering a large block of mostly secondary- growth forests (BirdLife International 2021). The majority of the forested areas on Leyte Island, including the Anonang- Lobi range, are confined to 500 m and above since most of the primary lowland forests had been cleared for logging, agriculture, and upland farming (Taylor et al. 2015).
During the assessment, the authors recorded and photographed the Utricularia populations in the area but no
1Philippine Eagle Foundation Inc., Philippine Eagle Center, Malagos, Baguio District, 8000 Davao City, Philippines
2Department of Biology, College of Arts and Sciences, Central Mindanao University, University Town, Musuan, Maramag, 8714 Bukidnon, Philippines
3University of the Philippines – Mindanao, Bago Oshiro, Mintal, 8000 Davao City, Philippines
*Corresponding author: [email protected] Date Submitted: 29 October 2022
Date Accepted: 03 June 2023
voucher specimens were collected. However, photographs of several plant parts and their habits were taken (e.g., flower, inflorescence, leaves, microhabitat, and habit) using a Canon EOS 800D camera. This population of U. striatula shows the following obvious distinguishing characters: (i) leaves pseudopetiolate and orbicular in shape, and (ii) 5-toothed corolla, which turns pink to purple (sometimes white) with yellow blotches near the base. All of these traits match those of U. striatula described by the Pelser et al. (2011 onwards), Thanikaimoni (1966), Taylor (1989), Janarthanam et al. (1992), and Naive et al. (2018). Also, the pickled collection of Naive et al. (2018) was examined for comparison and validation.
The current localities of U. striatula in the Philippines are in Mountain Province, Albay, Quezon, Romblon, and Aurora in Luzon; Negros Occidental in the Visayas (Pelser et al. 2011 onwards); and in Malaybalay and Quezon, Bukidnon in Mindanao (Naive et al. 2018). This is the first report of U.
striatula for the Eastern Visayas region effectively extending its distribution in the Philippines.
Habitat and Ecology. The population of U. striatula in Leyte grows as lithophytes along with bryophytes on damp rocks and stone slabs (Fig. 1). Two distinct subpopulations of U. striatula were found in the said locality—majority of the populations have pink corolla with yellow palate (Fig. 2b), while an isolated population has white corolla, yellow palate, relatively larger flowers, and grows in shady areas (Fig. 2c).
Slight differences were observed from that of the habitats of the common pink form growing in much exposed areas.
The discovered new population of U. striatula has an area coverage of ca. 250 m2 on the natural dike at an elevation of 511 masl, but the species was not observed in other parts of the Marabong River and its tributaries. Preliminary observations suggest adequate microclimate may have favored growth and reproduction of the newly reported population of U. striatula.
However, this hypothesis should be further tested by more observations.
The Leyte record is consistent with the observations of Naive et al. (2018) in Mindanao, in which they reported populations of U. striatula growing in an open damp area near the waterfalls and attached to the rocks (lithophytic), and growing on karst rocks often associated with bryophytes along the Pulangui River in Bukidnon. It is interesting to note that all reports of the species in the Philippines are all associated with
Volume 16 Issue 1 - 2022 | 63 Senarillos et al.: Utricularia striatula (Lentibulariaceae), a New Distribution Record from Leyte
Philippine Journal of Systematic Biology Online ISSN: 2508-0342
Figure 1. Habitat of the newly discovered populations of U. striatula in Barangay Kagbana, Burauen, Leyte, Philippines. (a) Marabong River, (b) & (c) Natural dike, boulders and stone slabs along the Marabong River. a–c: TLPS.
Figure 2. Flowers and habits of U. striatula Sm. in Barangay Kagbana, Buraeun, Leyte, Philippines (a) close-up photo of the flower, (b & d) Pink form of U. striatula Sm. (c & e) White form of U. striatula Sm. a: AVMT, b–e: TLPS.
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inland forests adjacent to fast-flowing pristine rivers, streams, waterfalls and mountain peaks with a good humidity. This habitat specificity of U. striatula could be the reason why it has not been documented in less vegetated, disturbed forested habitats. In the forest of Peninsular Malaysia, Haron & Chew (2012) reported that the majority of Utricularia species are lowland plants, whose distribution ascends through a variety of wetland habitats including streams, heath, and man-made, ephemeral wetlands. Furthermore, they reported that U.
striatula has much-restricted habitat preferences on wet and humid microhabitats, specifically in montane forests which descend to the lowland vegetation.
Global Distribution: This species occurs throughout much of tropical Africa, east through the Arabian Peninsula, Sri Lanka, India, Nepal, Bhutan to China and south through Myanmar, Thailand, Vietnam, Malaysia, Indonesia and the Philippines to Papua New Guinea (Lansdown et al. 2013).
Notes: In the Philippines, visual encounters of U. striatula have been reported by Wally Suarez in Solano, Nueva Vizcaya
in 2019 and in Palauig, Zambales between 2008-2009 (pers.
comm.). Further, U. striatula populations have also been documented in Claver, Surigao del Norte in February 2021;
Pantukan, Davao de Oro in 2018; Barangay Don Mariano Marcos, Lupon, Davao Oriental in 2021; and in La Union, San Isidro, Davao Oriental in 2021 by Rule (2021) and Keanu V.
Sitjar (pers. comm.). This species has also been documented by the National Museum of the Philippines (2021) in Mt.
Baloy, Panay Island, and in Mount Victoria, Narra, Palawan by Pin (2021).
Given the wide distribution range of U. striatula (Fig. 3), it is possible that it also occurs in other parts of the Philippines.
This species is likely to be more widespread in the country, and might have just been overlooked owing to their minute size. Thus, field-based biodiversity inventory studies should be given priority.
Conservation Status. In the latest assessment, U. striatula is classified as “Least Concern” under the IUCN Red List criteria (Lansdown et al. 2013). The species is excluded in the updated national list of threatened Philippine plants (DAO 2017-11).
Although there is no information available on its population trends, it is safe to assume that currently the species does not face any major threats given its wide distribution and the absence of reports of poaching for the horticultural trade and other uses. However, with its preference for pristine freshwater systems and forested habitats, the species may face population decline in the future if no protection scheme is applied in areas where the species is found.
Acknowledgements
The authors express their gratitude to Wally Saurez of Barangay Longos, Kalayaan, Laguna; Mark Gregory Rule of the Department of Environmental Science, College of Forestry and Environmental Studies, Mindanao State University; Keanu Sitjar of the Institute of Agriculture and Life Sciences, Davao Oriental State University; Yu Pin of the Philippine Taxonomic Initiative for generously sharing their data on the species occurrence within their respective localities; our colleague from the PEF Andrei Von Mariano C.
Tirona for letting us use his U. striatula photo; and Kenneth Paul P. Senarillos and Ken Allen M. Palaca for lay outing the figures. Due acknowledgments are also given to Mr. and Mrs. Rogelio Gloria and Prospira A. Gloria and the rest of the Barangay Kagbana Forest Guards for their assistance in the field. The valuable comments of anonymous reviewers made on an earlier version of this manuscript are appreciated.
This research is made possible with the approval and help from the Burauen local government and the Department of Environment and Natural Resources-Provincial Environment and Natural Resources Office (DENR-PENRO) in Tacloban City. This study was part of a biodiversity assessment for the Philippine Eagle reintroduction project in Leyte funded by the Mandai Nature, Forest Foundation Philippines, Insular Life Assurance Company and the Direct Aid Program of the Australian Embassy.
Figure 3. Distribution of U. striatula Sm. in the Philippines. Sites mentioned in the text 1) Mountain Province, 2) Salano, Nueva Vizcaya, 3) Palauig, Zambales, 4) Aurora, 5) Dolores, Quezon, 6) Mt.
Victoria, Narra, Palawan, 7) Albay, 8) Romblon, 9) Mt. Baloy, Panay Island, 10) Negros Occidental, 11) Burauen, Leyte*, 12) Claver, Surigao Del Norte, 13) Pantukan, Davao De Oro, 14) La Union, San Isidro, Davao Oriental, 15) Barangay Don Mariano Marcos, Lupon Davao Oriental, 16) Malaybalay, Bukidnon, 17) Quezon, Bukidnon.
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© Assocation of Systematic Biologists in the Philippines Literature Cited
BirdLife International. 2016. Pithecophaga jefferyi.
The IUCN Red List of Threatened Species 2016:
e.T22696012A93538566.http://dx.doi.org/10.2305/IUCN.
UK.20163.RLTS.T226 96012A93538566.en.
BirdLife International, 2021. Important Bird Areas fact sheet:
Anonang-Lobi Range. Downloaded from http://www.
birdlife.org on 08/05/2021.
[DENR] Department of Environment and Natural Resources.
2017. Updated National List of Threatened Philippine Plants and their Categories. Retrieved from https://www.
philippineplants.org/dao-2017-11.pdf
Haron, N.W. & M.Y. Chew, 2012. Medicinal and environmental indicator dpecies of Utricularia from montane forest of Peninsular Malaysia. The Scientific World Journal, 6:
1–5. https://doi.org/10.1100/2012/234820.
Janarthanam, M.K. & A.N. Henry, 1992. Bladderworts of India. Botanical Survey of India, Calcutta. Pp. 106–112.
Juniper, B.E., R.J. Robins & D.M. Joel, 1989. The Carnivorous Plants. London, UK: Academic Press. 353 pp.
Lansdown, R.V., S.G. Knees & A. Patzelt, 2013. Utricularia striatula. The IUCN Red List of Threatened Species 2013:e.T168752A1222438. https://doi.org/10.2305/IUCN.
UK.2013-1.RLTS.T168752A1222438.en.
Mallari, N.A.D., B.R. Tabaranza, Jr. & M. Crosby, 2001.
Key conservation sites in the Philippines: a Haribon Foundation and BirdLife International directory of Important Bird Areas. Makati City: Bookmark, Inc.
Naive, M.A.K., D.P. Buenavista & N.P. Mendez, 2018. New distributional records of Utricularia striatula Smith (Lentibulariaceae) in Mindanao, Philippines. Philippine Journal of Systematic Biology, 11(2): 1–4.
National Museum of the Philippines. 2021. Utricularia striatula along small streams of the montane forest of Mt. Baloy, Panay Island. Retrieved from https://
www.facebook.com/nationalmuseumofthephilippines/
photos/a.195151237175869/4326231564067795
Pelser, P.B., Barcelona, J.F. & Nickrent, D.L. (eds.), 2011 onwards. Co’s Digital Flora of the Philippines. www.
philippineplants.org.
Pin, Y. 2021. Utricularia striatula, an aquatic carnivorous plant.
South Palawan. Retrieved from https://www.facebook.
com/groups/141074462607292/posts/2951164414931602 Rule, M. G. 2021. Tiny carnivore-Utricularia or bladderworts
is a genus of small carnivorous plants that occur in fresh water and wet soil. Retrieved from https://www.
facebook.com/yambo.rule/posts/10215977299940158 Taylor, J., Mate, E., Hutchinson, R. O. & Eaton, J. A.
2015. Frontiers of the Philippines: Eastern Visayas.
BirdingASIA 24, 24–36.
Taylor, P., 1989. The genus Utricularia – a taxonomic monograph. Kew Bulletin. Additional Series, 14: 1–724.
Thanikaimoni, G., 1966. Pollen morphology of the genus Utricularia. Pollen et Spores, 8: 265–284.
Verma, P.K., J. Schlauer, K.K. Rawat & K. Giri, 2014. Status of insectivorous plants in northeast India. Carnivorous Plant Newsletter, 43: 49–58.
