Landslide and Subsidence Potential due to the Progressive Development of Cave Network in Ella-Wellawaya Area, Sri Lanka

Carbonate rocks are highly soluble. Sinkholes are formed by both the failure of solution cavities andthe rapid removal of fines from solution cavities in carbonate and metacarbonate rocks. Sri Lankanlandmass is composed of Proterozoic high-grade metamorphic rocks such as gneiss andmetacarbonates like marble. Large caves in Sri Lanka form in both marble and gneiss. A few landsubsidence events have occurred recently in Ella-Wellawaya area, which is a hilly terrain. In addition,some cases of groundwater table lowering, which has caused drying of dug wells have also beenrecorded within the area, apparently related to a major development project presently under way in thearea.The main objective of this paper is to draw the immediate attention of local researchers andauthorities whom are working on mitigation and management of disasters, groundwater and climatechange, showing the importance of carrying out detail studies on potential landslides and landsubsidence of Ella-Wellawaya area for avoiding and minimising loss of humans and properties.Preliminary surveys on some land subsidence cases and speleological studies including geology,hydrogeology and morphological mapping of the underground caves in the area have been activelycarried out. According to the results, it is shown that the subsidence is likely to be correlated with thecollapsing of cavities and weathered zones in metacarbonates, and disturbances to the groundwatertable. Field explorations done during the last two years have discovered several large undergroundcaves in the area some more than 100 m across. Most of the cave roofs have been thinned by thebreakdown of bedrock along weak zones such as joints. Since the process of collapse, trigged byweathering is continuing and patches and lenses of carbonate rocks observed in the caves are stillbeing dissolved, the expansion of the cave spaces is unending. Some of the chambers of these cavesare aligned parallel to the steep slopes in the Ella-Wellawaya area and some acted as undergroundwater conduits and storages during the rainy seasons. The Ella-Wellawaya area has been undergone achange in vegetation cover since the colonial period and hence the area is more prone to soil erosionwhich exposes the near surface natural cavities to the underground caves. Present human exposuresand interactions within the susceptible slopes have brought lives and properties under threat. Hencefuture land subsidence and landslide occurrences are highly predictable with the recent conditions inthe area and hence threat to human life and properties is high. The tourism industry, unique to the areacould particularly be affected. Hence such hazardous should properly be identified and demarcatedand the erosion triggered by present vegetation changes must properly be addressed.Keywords: Metacarbonate rocks, Subsidence, Ella-Wellawaya, Cave network, Erosio

Exploring the Plastic Collection and Recycling Trends in Sri Lanka

This study examined plastic waste management in Sri Lanka, concentrating on the contributing factors to plastic waste generation and collection. Data were gathered through a questionnaire survey from registered plastic recycling and management centres. The analysis revealed a positive correlation between tourist arrivals and plastic waste generation, indicating increased plastic waste production due to tourism. However, plastic waste collection negatively correlated with precipitation levels, suggesting that heavy rainfall hampers collection efforts. The study found HDPE, PVC, LDPE, and PP to be the most collected and recycled plastic types, whereas PS and PET recycling were less prevalent. The results demonstrate the need for enhanced recycling infra-structure and highlight the necessity for government participation in plastic waste management initiatives. The study recommends increasing waste collection and recycling during the tourist season. As well as, enhancing public and private awareness, there should be additional investment in recycling facilities. The findings offer crucial insights into plastic waste management in Sri Lanka, emphasizing the importance of collaborative efforts and comprehensive strategies to tackle plastic pollution

Impatiens jacobdevlasii Herath, C. Bandara & Gopallawa 2022, sp. nov.

Impatiens jacobdevlasii Herath, C. Bandara & Gopallawa sp. nov. (Figs. 1‒3 & 4 I–P) Type:— SRI LANKA, Central Province, Kandy District, Dothalugala Mountain, on the ground among rocks and mosses along stream, 1375 m a.s.l., 13 October 2018, Sanath Herath & Champika Bandara 2018-05. (holotype PDA!); Central Province, Kandy District, Thangappuwa –Alugallena nature trail, along shady embankments of the trail, 1512 m a.s.l., 02 June 2019, NBS/2019/ OL / TGP/009. (paratype PDA!). Diagnosis: Impatiens jacobdevlasii morphologically similar to I. truncata but differs by having pinkish or purplish color flowers with pink margin, bilobed upper petal of lateral united petals and yellow color centre blotch, linearlanceolate lateral sepal, 4–6 lateral nerve pairs, abaxially scattered pubescent and adaxially glabrous lamina. Description: Herb, Perennial, 30–60 cm tall; stem pale greenish, swollen at nodes, cylindrical, glabrous. Leaves simple, spirally arranged, lower part often naked and often crowded towards apex of stem, petiolate; Petiole ca. 2–3 cm long, glabrous, pale green; stipule minute, ca. 0.5–1 mm. Lamina lanceolate or elliptic-lanceolate, 2–8 (–10) × 1.5–3.5 (–4.5) cm, base subattenuate, acuminate at apex; adaxially dark green color with scattered minute hairs, abaxially pale green, glabrous, margin crenate or serrate with a single narrow tooth; setulose in between marginal teeth. Lateral nerves in 4–6 (–7) pairs, sub-opposite, prominent. Flowers solitary in the upper leaf axils, simple, pale pinkish or purplish with pink margins and rarely white. Peduncle 2.5–3.5 cm long, thin, pale green, scattered pubescent. Lateral sepals 2, linear-lanceolate, 3.5–4 × 0.7–0.9 mm, glabrous, slightly curved, pale green, pinkish towards apex, margins entire. Lower sepal 13–15 × 6–8 mm, navicular, white externally and internally with yellow patch at the centre, 1 mm long mucronate at apex; spur 3–4 mm long, pale yellowish, straight, cylindrical. Dorsal petal cucullate, 9–10 × 6–7 mm, concave, dorsally with a narrow crest terminating in a short pointed appendage, ca. 1.5–2 mm. Lateral petals united, 20–25 × 8–10 mm, 2-lobed; base of united lateral petals with yellowish blotch, upper petals about one-third the size of the lower petals; upper petal 7–9 × 5–7 mm, apex equally bilobed, pinkish or purplish shade towards apex and yellowish blotch in the centre; lower petal 15–18 × 8–10 mm, semi-oval, often notched at apex, base and inner margin of the distal lobes with minute pinkish or whitish ridge of papillae. Androecium 4–5 × 2 mm, glabrous, white. Stamens 5, connate, surrounding gynoecium. Filament ca. 1 mm, glabrous, white; style glabrous, ca. 0.5 mm long. Capsule green, 10–12 × 5–7 mm, broadly fusiform, 5-angled, pilosulose, apex acute, rostellate, fleshy; Seeds 1–4, 5–7 × 3–5 mm, obovoid, slightly compressed. Distribution: Impatiens jacobdevlasii is known from Dothalugala Mountain and Thangappuwa area in Knuckles massif of Sri Lanka. Habitat and ecology: Impatiens jacobdevlasii is known only from two locations in South-eastern region of Knuckles massif. Small populations of this species are distributed in the reported area. The overall number of mature individuals is estimated as ˂ 80 in the both populations from field observation. Both locations are belongs to lower montane evergreen forests at elevation of 1300–1500 m a.s.l. (Gunatilleke and Ashton 1987). One population was recorded from Dothalugala Mountain (1375 m a.s.l.) with ˂30 individuals and other from Thangappuwa (1512 m a.s.l.), population comprise with 2–3 subpopulations; 10–15 individuals per each. The new species is usually found on the ground among mosses and rock boulders along streams. This species mostly refer well-shaded forest cover and associated species are Rhynchoglossum notonianum (Wall) B.L. Burtt (1962: 170), Strobilanthes sexennis Nees (1837: 312), Ophiorrhiza pectinata Arnott (1836: 338), Phaius wallichii Lindle (1831: 46) and Begonia malabarica Lamarck (1785: 393). In the wild, this new species facing threat of extinction due to the low number of plants representing the entire population, population decline and its limited distribution. Dothalugala population shows significant decrease through the 2016–2022 period, approximately 80% of the population. The habitats of the new species associated with existing nature trails in Knuckles mountains (Bambaradeniya & Ekanayake 2003). Dothalugala population located near a stream in existing Deanston–Dothalugala nature trail and Thangappuwa population located in wet, rocky surfaces along the existing Thangappuwa–Alugallena nature trail. Any situation in road clearing, weeding, constructions or maintaining, authorities should focus the attentions for management and further conservation attempts on this new species. Thus, I. jacobdevlasii has a great potential for horticultural applications due to its wide color range of flowers (Fig. 3) and few plants were cultivated at Royal Botanical Garden, Peradeniya, Sri Lanka. Phenology: Flowering and fruiting all around the year. Etymology: The specific epithet is named in honour of Dr. Jacob de Vlas, a Dutch biologist and the author of the tri-volume series of the ‘Illustrated field guide to the flowers of Sri Lanka’ in 2008–2019 documenting over 3000 native and introduced species of the Island. The common name for the species is Vlas’s balsam. Proposed IUCN conservation assessment: Based on current knowledge, the Extent of Occurrence (EOO) and Area of Occupancy (AOO) was estimated using GeoCAT (Moat 2007) as ~ 2 km 2 and 12 km 2 respectively. From the available data, we classify I. jacobdevlasii as ‘Critically Endangered’ (CR: B1+B2b (ii,iii,v); C2a (i,ii); D) in accordance with IUCN guidelines (IUCN 2019). Additional specimens examined: SRI LANKA. Impatiens truncata:—MATALE DISTRICT: Midlands Estate to Laggala, 700 m a.s.l., Nov. 1978, Grey-Wilson & Silva 3002 (PDA!); Matale to Illukkumbura road, July 1974, Sumithraarachchi 418 (PDA!). KANDY DISTRICT: Corbet’s Gap, Rangala to Looloowatte (Loolwatte), 1300 m a.s.l., September 1969, Grupe 237 (PDA!); Kalupahana Forest, Knuckles Mts., 1250 m a.s.l., July 1973, Jayasuriya & Balasubramaniam 1220 (PDA!); Hantana, s. coll. C. P . 2426, pro parte (PDA!);. NUWARA ELIYA DISTRICT: between Ramboda and Nuwara Eliya, 1500 m a.s.l., Nov. 1978, Grey-Wilson & Wickramasinghe 3035 (PDA!); Pattipola to Farr Inn, Horton Plains, Nov. 1973, Sohmer, Jayasuriya & Eliezer 8523 (PDA!). Impatiens jacobdevlasii:— KANDY DISTRICT: Thangappuwa–Alugallena nature trail, Knuckles Mt., 1540 m a.s.l., December 2019, Champika Bandara & Shashee Dilrukshi 2019-13 (PDA!)Published as part of Bandara, Champika, Herath, Sanath Bandara, Gopallawa, Bhathiya & Attanayake, Achala, 2022, Impatiens jacobdevlasii (Balsaminaceae), a new species from Knuckles massif of Sri Lanka, pp. 181-187 in Phytotaxa 543 (3) on pages 182-186, DOI: 10.11646/phytotaxa.543.3.2, http://zenodo.org/record/646032

Gastrodia munasinghae Atthanagoda, C. Bandara & Kumar 2023, sp. nov.

<i>Gastrodia munasinghae</i> Atthanagoda, C.Bandara & Kumar <i>sp. nov.</i> (Figs. 1 A–E, 2 & 3) <p> <b>Type:—</b> SRI LANKA, Sabaragamuwa Province, Ratnapura District, Maliboda –Sri Pada trail, Samanala Nature Reserve, 30 March 2022, <i>AKAG10.2022</i> (holotype PDA!; isotype PDA!-spirit); Sabaragamuwa Province, Ratnapura District, in a fragmented forest patch near a tea plantation between Panapola–Pothupitiya, 4 April 2022, <i>AKAG11.2022</i> (paratype PDA!).</p> <p> <b>Diagnosis:—</b> <i>Gastrodia munasinghae</i> is morphologically allied with <i>G. uraiensis</i> Hsu & Kuo (2010: 244) and <i>G. fontinalis</i> Lin (1987: 129) in having similar rough-surfaced brown coloured perianth tube, petals attached at the tip of junction of lateral sepals, orange winged column, stigma placed towards the base of the column and two rounded callus at the base of the labellum, however, the new species differ in having taller plants in former, 10–18 cm tall (vs. 1–4 cm tall plants in <i>G. uraiensis</i> and 7–12 cm tall in <i>G. fontinalis</i>), inflorescence with 4–8 flowers (vs. 1–3(–5) flowers in <i>G. uraiensis</i> and 1–3 flowered in <i>G. fontinalis</i>), labellum 4–4.5 mm long (vs. 6–7 mm long labellum in both <i>G. uraiensis</i> and <i>G. fontinalis</i>) and dull green-blue mesochile and bright orange color epichile in the labellum (vs. reddish brown coloration in <i>G. uraiensis</i> and <i>G. fontialis</i>). <i>G. munasinghae</i> can be also distinguished from <i>G. bambu</i> Metusala (2017: 212) in having 12 mm long, up to 10 mm wide, widely opening smaller flowers (not widely opening, 17 <i>–</i> 20 mm long and 14 <i>–</i> 16 mm wide larger flowers in latter), ovate-orbicular, 4–4.5 mm long and 3–3.2 mm wide labellum (oblonglanceolate, 10 <i>–</i> 12 mm long × 3.5 <i>–</i> 4 mm wide labellum in latter) and erect, 5–5.5 mm long, 2.8–3 mm wide column (slightly arcuate, 10 <i>–</i> 12 mm long, 2 <i>–</i> 2.5 mm wide column in latter).</p> <p> <b>Terrestrial</b> holomycoheterotrophic herbs, 10–18 cm tall. <b>Rhizome</b> tuberous, fusiform or cylindrical, 7–13 × 1.2–2.3 cm, plagiotropic, hairy, membranous triangular scales emerging from the nodes. <b>Raceme</b> erect, peduncle 8–13 cm long, glabrous, pale brown in color, with 3–5 membranous semi-transparent sheaths; sheaths tubular, 4–5.5 mm long. <b>Inflorescence</b> erect with 4–8 flowers, rachis <i>ca</i>. 4–6 cm long. <b>Floral bracts</b> triangular, 5–6 mm, acute, dark greyish brown to dark brown in color, membranous, margin slightly lacerate, base surrounding the pedicel. <b>Pedicel</b> orange-brown, <i>ca.</i> 8–11 mm long, 2.5–3.2 wide. <b>Flowers</b> resupinate, sepals and petals fused to form perianth tube, widely opening; apical part free, forming a five-lobed front; ridges 4; 12 mm long, up to 10 mm wide, outer surface greyish brown, verrucose, inner surface dark brown in color with dull orange-brown under lateral sepals and greyish under dorsal sepal and petals; lobe of dorsal sepal triangularly ovate, 6 × 4.5 mm, obtuse, slightly convex, brown, margins entire; lobes of lateral sepals triangularly ovate, 4.5 × 5 mm, brown, margins entire; petal lobes ovate-elliptic, smaller than sepal lobes, 3.5 × 2 mm, pale brown; labellum adnate to the foot of column, ovate-orbicular, 4–4.5 × 3–3.2 mm, hypochile short, ca. 1 mm long, broader at the base and narrowing towards the epichile, inflated, with 2 globose calli at the base, callus 0.5–0.8 mm in diameter, pale orange-yellow colored with dark brown shiny surface; epichile ovate, 3.5–3.8 mm long, 3.1–3.3 mm wide, obtuse, bright orange at the apex, pale yellowish green along the middle and pale brownish-orange at the base, slightly tapering toward apex with a pair of lamellae or short ridge on the upper surface, longitudinally channeled underneath of the lip from base to the tip. <b>Column</b> erect, 5–5.5 × 2.8–3 mm, whitishcream with grey-brown colored at base, slightly extended into a short foot, ca. 1.5 mm long, 2–2.5 mm wide; stelidia falcate, 2.5–3 × 0.5–0.6 mm, apex acute, extended slightly beyond the anther cap, red-orange; rostellum prominent; stigma located towards the lower half of the column on a raised but slightly inclined and convex platform. <b>Anther cap</b> cucullate, ca. 1.5 mm in diameter. <b>Pollinia</b> 2, clavate, ca. 1.2 mm long. Ovary obconical, 3.5–4 mm long, ca. 2.5 mm wide, dark brown, verrucose, ribbed. <b>Capsule</b> erect, fusiform, verruculose, ca. 2.3–2.7 cm long, 4.5–5 mm wide, on a longer stalk of variable length,> 2 cm long, pale orang-brown with darker stripes, borne on an elongated pedicel, up to 18–32 cm long, pale brown, slender and terete.</p> <p> <b>Phenology:—</b> Flowering and fruiting individuals were observed from early January to April in different subpopulations. The subpopulations in Samanala Nature Reserve begin flowering from January to April and the population in lowland wet zone flowering only in March and April.</p> <p> <b>Etymology:—</b> The specific epithet honors Mrs. Liliyan Chandralatha Munasinghe, the second author’s mother for her unconditional love, support and encouragement.</p> <p> <b>Distribution:—</b> <i>Gastrodia munasinghae</i> is endemic to Sri Lanka and thus far known from the sub-montane forests in Maliboda–Sri Pada trail and Kuruwita–Eratne–Sri Pada trail in Samanala Nature Reserve, Central Highlands of Sri Lanka and fragmented forest patch of the lowland rain forests bordering to a tea plantation near Pothupitiya in Ratnapura District (Fig. 7).</p> <p> <b>Habitat and ecology:—</b> This species grows under the shade of <i>Strobilanthes lupulina</i>, <i>Strobilanthes zeylanica</i> (Acanthaceae) and <i>Ochlandra stridula</i> (Poaceae) species in the lowland forests between 400 and 715 m a.s.l and between 600 and 1000 m a.s.l in foothills of the Adam’s Peak on humus-rich decaying leaf litter. The rhizomes are buried up to 2–4 inches deep in the ground. Other notable Orchidaceae members sharing the same habitat were <i>Sirhookera lanceolata</i>, <i>Zeuxine regia</i>, <i>Anoectochilus</i> sp., <i>Habenaria crinifera</i>, and <i>Oberonia</i> sp. at Pothupitiya and <i>Zeuxine reginasilvae</i> from Maliboda–Sri Pada trail.</p> <p> <b>Taxonomic notes:—</b> <i>Gastrodia munasinghae</i> morphologically close resembles <i>G. uraiensis</i>, <i>G. fontinalis</i> and <i>G. bambu</i> but, is readily distinguished in having 10–18 cm tall plant habit; 4–8 flowered inflorescence; 12 mm long and 10 mm wide flowers; ovate-orbicular, 4–4.5 mm long and 3–3.2 mm wide, dull green-blue colored mesochile and bright orange colored epichile in the labellum and erect, 5–5.5 mm long, 2.8–3 mm wide column. The brown-colored <i>Gastrodia</i> species are morphologically similar to each other on their external appearances but, all species have unique morphological characters and distribution ranges. Clements and Jones (2019), combined this group of brown color <i>Gastrodia</i> species <i>s.l.</i> to the genus <i>Demorchis</i> M.A.Clem. & D.L.Jones. However, this genus is not accepted and synonymized under the genus <i>Gastrodia</i> (Jones & Clements 2004, Clements & Jones 2019, POWO 2023).</p> <p> <b>Conservation status:—</b> <i>Gastrodia munasinghae</i> grows in sub-montane and lowland forests in Sabaragamuwa Province with a small population size of 8 mature individuals found during the first visit in Eratne–Sri Pada trail in Samanala Nature Reserve far back in 2005. Unfortunately, this species was never seen again at this locality after repeated visits until 2022. Later, another subpopulation was discovered in 2012 in Maliboda–Sri Pada trail and the number of mature individuals varied in 2012, 2016, 2020 and 2022 with 6, 3, 8 and 4 respectively (Fig. 8). Recently, another subpopulation has been discovered in 2022 at a fragmented forest patch adjacent to a tea plantation along Panapola– Pothupitiya road, containing 11 flowering individuals. At the first two sites, the habitat is heavily disturbed due to the frequent clearance of the existing pilgrim trails of the Sri Pada (Adam’s Peak) and pollution. The other subpopulation in Pothupitiya is also facing the risk of extinction due to anthropogenic disturbances and land use changes. Area of Occupancy (AOO) and the Extent of Occurrence (EOO) was estimated using GeoCAT (Bachman <i>et al</i>. 2011) as 12 km 2 and ~ 32 km 2 respectively. These mycoheterotrophic species are extremely habitat specific and are susceptible to even minor disturbance. Hence, based on the available data, three sites are considered as three locations. As such the total number of mature individuals encountered so far is 27, however, as these mycoheterotrophic species sometimes remain dormant with underground tubers, hence we optimistically estimate total number of mature individuals to be less than 50. Accordingly, the species is assessed as Critically Endangered (CR D), based on current data and following IUCN guidelines (IUCN 2022).</p>Published as part of <i>Bandara, Champika, Atthanagoda, Anusha Gayan, Bandara, Nadeesha Lewke & Kumar, Pankaj, 2023, The study of the tribe Gastrodieae (Orchidaceae, Epidendroideae) in Sri Lanka I: two new species of Gastrodia, pp. 115-130 in Phytotaxa 622 (2)</i> on pages 116-117, DOI: 10.11646/phytotaxa.622.2.2, <a href="http://zenodo.org/record/10084582">http://zenodo.org/record/10084582</a&gt

Gastrodia thilakapremae Atthanagoda, C. Bandara & Kumar. Voucher 2023, sp. nov.

<i>Gastrodia thilakapremae</i> Atthanagoda, C.Bandara & Kumar <i>sp. nov.</i> (Figs. 1 F–K, 4 & 5) <p> <b>Type:—</b> SRI LANKA. Central Province, Kandy District, Kondagala in Loolkandura Estate, 26 May 2022, <i>AKAG12.2022</i> (holotype PDA!; isotype PDA!-spirit); Sabaragamuwa Province, Ratnapura District, Galwangediya, Eratne –Sri Pada trail, Samanala Nature Reserve, 10 June 2022, <i>AKAG13.2022</i> (paratype PDA!; PDA!-spirit).</p> <p> <b>Diagnosis:</b> <i>Gastrodia thilakapremae</i>, a Sri Lankan endemic, is not easy to differentiate from a Japan and Taiwan native <i>G. gracilis</i> Blume (1856: 174) as they look similar in various morphological features, however they are different on a closer look. <i>Gastrodia thilakapremae</i> has green flowers with green opaque petals; triangular floral bracts, 4.5–6 mm long; orange labellum (darker towards apex and fading towards base), length slightly shorter than column with anther cap, almost triangular to ovate in shape abruptly narrowing towards the apex with constrictions on the margins, lacking distinct longitudinal bands of intermittent warts towards the centre, with a pair of triangular lamellae on the centre between the constrictions; hypochile broad (> 2 mm wide) and orange on upper and white on the lower surface; epichile lower margin slightly flat; column with stelidia wings broadening from nearly at the base of the column till just below the apex of stelidia and capsules fusiform, 2.5–3.5 cm long. Whereas, <i>G. gracilis</i> has dull greenish-brown flowers with darker pale brown petals; floral bracts ovate or elliptic shaped, 2–4 mm long; labellum orange with white longitudinal bands before the margin on either side, length slightly longer than the column with anther cap, almost triangular but gradually narrowing towards apex lacking any constrictions on the margin; distinct 5 longitudinal divergent bands of intermittent warts running from base to the middle of the labellum, with a pair of ellipsoid lamellae towards the apex; hypochile narrow (<2 mm wide) and orange on both surfaces; lower margin of epichile raised up to fill the gap caused due to lack of wings on lower margin of the column; column with broadening of stelidia wings not starting from base but after 1/3 rd of the length from base and obovoid or ellipsoid capsules that are 2–2.3 cm long (see Fig. 6).</p> <p> <b>Terrestrial</b>, holomycoheterotrophic herbs, 55–75 cm tall. <b>Rhizome</b> tuberous, ellipsoid, 4–6 cm long, 1.0– 1.3 cm in diameter, sparse hairs dispersed along the gaps between closely placed membranous triangular scales emerging from the nodes. <b>Raceme</b> erect, peduncle 40–46 cm long, glabrous, pale brown or greyish-brown, with 8–10 membranous semi-transparent sheaths; sheaths tubular, pale brown, 5.5–7 mm long. <b>Inflorescence</b> erect with 4–6 flowers, rachis ca. 4–6 cm long. <b>Floral bracts</b> triangular, 4.5–6 mm, acute, dark brown, base surrounding the pedicel. <b>Pedicel</b> dull green-brown to dark brown, verrucose, ca. 4–6 mm long. <b>Flowers</b> resupinate, perianth tube formed by fusion of sepals and petals, apical end partially opened; perianth tube slightly arched downwards, nodding, 2.2–2.5 cm long, up to 1.6–1.8 cm wide, globose, outer surface dull green, verruculose; inner surface pale green; lobe of dorsal sepal broadly ovate, 9–10 × 6 mm, apex obtuse, slightly convex, fleshy, yellowish-green to pale green, margins entire; lobes of lateral sepals broadly ovate, 8–9 × 4.5–5.5 mm, obtuse, fleshy, margins entire, yellow-green on outside, pale green inside; petal lobes 2, orbicular with contracted base, curled, smaller than sepal lobes, 5.5 × 5 mm, obtuse, margin crenate, pale green; labellum adnate to column foot, ovate to rhomboid, 5.5–6.3 mm long, 2.3–4.5 mm wide, enclosed within the perianth tube, orange, longitudinally channeled underneath; epichile abruptly narrowing at the apex, 5.2–5.4 mm long, 3.5–4.5 mm wide, dark orange, apex yellow, irregularly crisped on the margin; hypochile contracted into a claw, ca. 0.6–0.8 mm long, 2.1–2.3 mm wide, pair of lamellae or ridge towards the apex; pair of globular, waxy calli at the base, 1.1–1.3 mm in diameter. <b>Column</b> erect, narrowly ovate to elliptic, 5–5.5 mm long, 3–3.2 mm wide, apex retuse, pale green-white with light brown colored on both sides, bearing stelidia on either sides and a short foot below; stelidia distinct, falcate, spread out, ca. 4.5 × 1.3 mm, apex acute with a pointed tip, base slightly angled, pale greenish; foot short, 1–1.2 mm long, brown-green; rostellum prominent; stigma located towards the base of the column on a raised, but inclined platform. <b>Anther cap</b> cucullate, ca. 2.2 mm in diameter; pollinia 2, clavate, ca. 2 mm long; ovary obconical, 3.5–3.8 mm long, ca. 2 mm wide, dark brown, verrucose, ribbed. <b>Capsule</b> erect, fusiform, verruculose, ca. 2.5–3.5 cm long, 0.7–0.9 cm wide, dark brown with darker stripes, borne on an elongated pedicel; pedicel with capsule up to 4–8 cm long, brown, slender and terete.</p> <p> <b>Phenology:—</b> Flowering and fruiting observed during May to December in separate subpopulations. Flowering season of the subpopulations in Samanala Nature Reserve show wide range than the other population in Loolkandura. Flowering and fruiting individuals were observed during May to November at the Samanala Nature Reserve in different years according to the field observations. The Loolkandura subpopulation flowered in December. However, flowering and fruiting individuals were observed simultaneously in same population.</p> <p> <b>Etymology:—</b> The specific epithet honors Mr. Atthanagoda Kankanamalage Thilakaprema, the second author’s father for his support and guidance.</p> <p> <b>Distribution:—</b> <i>Gastrodia thilakapremae</i> is endemic to Sri Lanka and occurs throughout sub-montane forest at Kondagala in Loolkandura Estate, Kandy District; in the sub-montane and montane forests of the Samanala Nature Reserve in Central Highlands of Sri Lanka at Galwangediya on Kuruwita–Eratne–Sri Pada trail and Mahagalthalawa on Moray Estate–Sri Pada trail in Ratnapura District (Fig. 7).</p> <p> <b>Habitat and ecology:—</b> This species is found on montane and sub-montane forests between 1500–2000 m a.s.l and under the shade of <i>Strobilanthes</i> (Acanthaceae) shrubs among the thick leaf litter. Mostly prefers partially open canopy and humus rich soil. Other notable members of Orchidaceae family sharing the same habitat were, <i>Liparis elliptica</i>, <i>Calanthe masuca</i>, <i>Zeuxine</i> sp. and <i>Oberonia</i> sp. in Samanala Nature Reserve. <i>Oberonia scyllae</i>, <i>Peristylus aristatus</i>, <i>Chiloschista fasciata</i> and <i>Phaius wallichii</i> in Kondagala, Loolkandura Estate.</p> <p> <b>Conservation status:—</b> <i>Gastrodia thilakapremae</i> occurs in both montane and sub-montane forests at 3 different sites in Sri Lanka, one in Kandy District, Central Province and two in Ratnapura District, Sabaragamuwa Province. This species was recorded from Kondagala in Loolkandura Estate in 2012 where it was seen in bloom regularly in 2016, 2018, 2019, 2020, 2021 and 2022 with 4, 6, 2, 11, 5 and 6 individuals respectively (Fig. 8). Two other subpopulations were found in 2020 from Galwangediya area, Eratne–Sri Pada trail and Mahagalthalawa, Moray Estate–Sri Pada trail in Samanala Nature Reserve and both of sites were revisited in 2022. The subpopulation in Galwangediya area, Eratne–Sri Pada trail consisted of 11 mature plants in 2020 and 16 in 2022. Mahagalthalawa subpopulation is the smallest among all with 4 individuals in 2020 and 3 in the following visit in 2022. The habitats of this species in Sri Pada are also threatened due to the clearance of banks and roadsides during the pilgrim season. The population of Kondagala in Loolkandura Estate is faintly protected with a good forest cover but, not safe at all with the human interactions. There is an inferred threat of decline in the quality of habitat. Hence, three sites are considered as three locations. This species may remain dormant with underground tubers, and hence, an optimistic estimate of less than 50 mature individuals has been inferred. The Area of Occupancy (AOO) and the Extent of Occurrence (EOO) were 12 km 2 and ~ 186 km 2 respectively according to GeoCAT (Bachman <i>et al</i>. 2011). Based on available information this species can be assessed as Critically Endangered (CR D) owing to extremely small population size following IUCN guidelines (IUCN 2022).</p> <p> <b>Taxonomic notes:—</b> <i>Gastrodia thilakapremae</i> is morphologically similar with the group of species in <i>Leptogastrodia</i> M.A.Clem & D.L.Jones (≡ <i>Gastrodia</i>), but differs from all other species by having 55–75 cm tall plant habit; 2.2–2.5 cm long, up to 1.6–1.8 cm wide, dull green color flowers with ovate to rhomboid, 5.5–6.3 mm long, 2.3–4.5 mm wide, orange color labellum and 2.5–3.5 cm long, fusiform capsules.</p>Published as part of <i>Bandara, Champika, Atthanagoda, Anusha Gayan, Bandara, Nadeesha Lewke & Kumar, Pankaj, 2023, The study of the tribe Gastrodieae (Orchidaceae, Epidendroideae) in Sri Lanka I: two new species of Gastrodia, pp. 115-130 in Phytotaxa 622 (2)</i> on pages 121-126, DOI: 10.11646/phytotaxa.622.2.2, <a href="http://zenodo.org/record/10084582">http://zenodo.org/record/10084582</a&gt

Integrating bioacoustics, DNA barcoding and niche modeling for frog conservation – The threatened balloon frogs of Sri Lanka

Discovering and monitoring anuran populations that are in decline, and ascertaining boundaries for cryptic and rare species, is a challenge for their conservation management. Here, we integrate three techniques, bioacoustics (call), niche modeling and DNA barcoding as a test case to investigate how the combination of these methods can enhance search efficiency for previously unknown populations, especially for those species that are threatened. As a focal group, we considered a clade in the genus Uperodon earlier referred to as Ramanella, represented by four endemic species in Sri Lanka (U. nagaoi – Endangered; U. palmatus – Critically Endangered; U. obscurus – Vulnerable and U. rohani – possibly Least Concern); we focus on the two highly threatened species (U. nagaoi and U. palmatus). We used mitochondrial DNA barcodes (16S rRNA) to link species accurately to their call and subsequently predicted species distributions using MaxEnt-based niche modeling of known species locations and forest cover data to increase the efficiency of searching for new populations. Lastly, we analyzed call data for accurate and rapid identification of new and viable populations. Following enhanced predicted distribution models, we visited 14 potential sites and sampled for calls of the two highly threatened species. Within a period of two weeks of fieldwork, we discovered two new populations of U. nagaoi and one population of U. palmatus by identifying their calls in areas predicted by niche modeling; we also confirm species identities at several previously unconfirmed locations. Finally, we included the new locations to enhance the distributional predictions for the threatened species. We discuss our results in the context of integrating methods to facilitate conservation of rare and threatened frog species. Keywords: Anura, Distribution modeling, Exploration, Population monitoring, Species boundaries, Vocalizatio

Methanol Extract of Holarrhena antidysenterica Inhibits the Growth of Human Oral Squamous Cell Carcinoma Cells and Osteoclastogenesis of Bone Marrow Macrophages

Oral squamous cell carcinoma (OSCC) frequently invades mandibular bone, and outcomes for treatment with surgical resection are typically poor, ultimately resulting in death. Holarrhena antidysenterica L. (Apocynaceae), distributed throughout Sri Lanka and India, has been used as a folk remedy to treat various diseases. Treatment with methanol extract of H. antidysenterica bark (HABE) inhibited cell viability and BrdU incorporation and induced apoptotic cell death in Ca9-22 gingival and HSC-3 tongue SCC cells. Flow cytometric analysis indicated that HABE treatment preferentially induces apoptotic cell death via increasing the sub-G1 peak in Ca9-22 cells and cell cycle arrest at the G1 phase in HSC-3 cells. HABE treatment in the presence of zVAD-fmk, a pan-caspase inhibitor, rescued cell viabilities in both OSCC cell lines. The ratio of Bax to Bcl-2 increased with reductions in the Bcl-2 protein expression, and the activation of caspase 3 and subsequent cleavage of PARP was detected in HABE-treated Ca9-22 and HSC-3 cells. Furthermore, HABE treatment at noncytotoxic concentrations inhibited osteoclast formation in RANKL-stimulated bone marrow macrophages. Taken together, HABE possesses the inhibitory activity on the growth of OSCC cells and antiosteoclastogenic activity. Therefore, HABE may be a promising alternative and complementary agent for preventing and treating OSCC

Trichoglottis quadriga Atthan., C. Bandara, Peiris & Kumar 2023, sp. nov.

<i>Trichoglottis quadriga</i> Atthan., C.Bandara, Peiris & Kumar <i>sp. nov</i>. (Figs. 1–3) <p> <b>TYPE:</b> SRI LANKA. Sabaragamuwa Province, Ratnapura District, Samanala Nature Reserve, Mukkuwatte –Sri Pada Trail, 1145 m a.s.l., 23 March 2022, <i>AKAG 15.2022</i> (holotype-PDA!); <i>AKAG 16.2022</i> (topotype PDA!-spirit).</p> <p> <b>Diagnosis:</b> <i>Trichoglottis quadriga</i> is morphologically very similar to a Vietnamese endemic, <i>T. canhii</i>, but it can be easily distinguished from the latter in having leaf apex bi-lobed with acute lobules (vs. leaf apex bi-lobed with rounded lobules); 4-flowered racemes (vs. 5–12-flowered racemes); longer terete spur, more than half the length of the pedicel and ovary, 3.2 mm long, 1.2 mm wide, with bi-lobed apex (vs. shorter, broadly conical spur, less than half of length of pedicel and ovary, 1.4–1.8 mm long, 1.2–1.5 mm wide, with round apex); larger labellum (5.5 mm long and 3.5 mm wide) (vs. shorter labellum, 3.8–4.0 mm long, 1.8–2.0 mm wide), with longer side lobes; rostellum strongly beaked with the beak arching upwards (vs. rostellum feebly beaked); lobes of pollinia less than half the length of the caudicle and viscidium (vs. lobes of pollinia more than half the length of stipe and viscidium).</p> <p> <b>Epiphytic</b> monopodial herb. <b>Roots</b> numerous, terete, 3.0‒ 16.5 cm long, 0.8‒1.2 mm in diameter, flexuose, greenish-grey, glabrous, arising from basal part of the stem. <b>Stem</b> unbranched, stout, rigid, 0.7‒2.0 cm long, 0.4‒0.6 cm in diameter, greenish with silvery white velamen; internodes 3.0‒ 4.5 mm long, rarely branched near base. <b>Leaves</b> 3‒7, almost sessile, distichous, narrowly lanceolate to oblanceolate, margins entire and wavy, 4‒8(‒12) cm long, 0.4‒0.7 cm wide, arching, obliquely bi-lobed at the apex, longer lobule 1 mm long, shorter lobule 0.5 mm long, acute, midrib keeled, extended to a pointed setae in between lobules, ca. 0.2‒0.3 mm long. <b>Inflorescence</b> 4-flowered racemes, 1.1‒ 4.6 cm long, arising from stem through the leaf sheaths on internodes. <b>Peduncle</b> stout, terete, rigid, 1.5‒2.0 cm long, 0.9–1.3 mm in diam, greenish; with 2–3 persistent, triangular sterile bracts, 1.0– 1.2 mm long and wide, appressed to the peduncle. <b>Rachis</b> irregularly angled in cross section, 1.0– 1.5 mm in thick. <b>Pedicel</b> and <b>ovary</b> almost cylindric, slightly swollen in upper half, ca. 5.5‒6.0 mm long, curved, glabrous, green when unfertilized. <b>Flowers</b> widely opened, sepals and petals spreading, 9.0‒ 10 mm across, sepals and petals dull-yellow speckled with brown; lip white and spur pale yellow; column base brown and operculum light dull yellowish to almost whitish; pollinia pale yellowish. <b>Floral bracts</b> persistent, triangular, 0.7 mm long, 1 mm broad, acute, concave, dull greenish to light brown. <b>Dorsal sepal</b> oblanceolate, 9.0 mm long, 1.8 mm wide, narrowly obtuse, obtuse, 3-veined. <b>Petals</b> linear-elliptic to linearoblanceolate, 3.5 mm long, 1.6 mm wide, obtuse, 3-veined. <b>Lateral sepals</b> oblique-falcate, 4.3 mm long, 1.7 mm wide, apex rounded, 3-veined. <b>Labellum</b> 5.5 mm long, 3.5 mm wide (length from the base of column to the apex of median lobe), firmly attached to the column, spurred, elongate disc at the base, 3-lobed in the apical half; disc terete, channeled longitudinally on the upper side with slightly winged and raised margin, channel with dense soft hairs inside, leading to the spur; median lobe glabrous, fleshy, almost hexagonal, 3.2 mm long, 2.2 mm wide, margin crenulate indistinctly forming 5-lobules, lobules obtuse, prominent hollow on the ventral surface at the base; side lobes prominent, thumblike, up to ca. 1 mm long, erect and fleshy. <b>Spur</b> terete, 3.2 mm long, 1.2 mm diameter, apex equally bi-lobed, sparsely hairy on the inner margin with a bifid callus arising from the back wall of spur and ending at the throat, ca. 0.5 mm. <b>Column</b> short, 1.5 mm long, 1.2 mm diameter, stout, erect, broadly cylindrical, foot inconspicuous. <b>Rostellum</b> small, bifid, ca. 1.0 mm long, 0.5 mm wide, greenish-brown, extended into a prominent beak, beak arched upwards. <b>Operculum</b> hemispherical, 2 mm long, 1.2–1.4 mm wide, with a prominent beak oriented in parallel above the beak of the rostellum. <b>Anther</b> terminal, 2 loculed, 1.8 mm long, 2.0 mm wide. <b>Pollinia</b> 4, in 2 pairs, each lobe with 2 unequal sized pollinia tightly appressed to each other into a globular structure, 0.3‒0.4 mm in diameter each; stipe clavate, 1.6–1.8 mm long, with each lobe of pollinia attached on the broader side of the stipe; viscidium ovate, ca. 0.15‒0.20 mm long. <b>Ovary and pedicel</b> clavate, 5.3–5.5 mm long. <b>Capsule</b> fusiform or almost clavate, 2.0– 2.5 cm long, 0.6–0.7 cm diameter, dull green, dotted with dark purple spots and streaks, strongly ribbed.</p> <p> <b>Phenology:</b> Flowering and fruiting observed during November to March.</p> <p> <b>Etymology:</b> The specific epithet ‘quadriga’ in Latin stands for the word ‘team’ in English, and is used here appreciating the teamwork of young botanists and naturalists in Sri Lanka for describing this new species.</p> <p> <b>Vernacular name:</b> Samanala cherub orchid.</p> <p> <b>Distribution:</b> <i>Trichoglottis quadriga</i> is so far known from Mukkuwatte‒Sri Pada trail in Samanala Nature Reserve, Diyawilla, Rassagala, Bambarabotuwa and Pettigala in Sabaragamuwa Province. Endemic to Sri Lanka.</p> <p> <b>Habitat and ecology:</b> <i>Trichoglottis quadriga</i> grows in montane and sub-montane forests at 900‒1800 m a.s.l. in Central Highlands of Sri Lanka. The new species is a strict canopy-dweller, growing 6‒15 meters above the ground level epiphytic on medium-sized stumps and branches of lianas and trees of <i>Entada rheedei</i> Sprengel [Fabaceae], <i>Horsfieldia iryaghedhi</i> (Gaertner) Warburg [Myristicaceae], <i>Macaranga peltata</i> (Roxburgh) Müller Argoviensis [Euphorbiaceae], <i>Cullenia ceylanica</i> (Gardner) Wight ex K.Schumann [Malvaceae], <i>Dipterocarpus glandulosus</i> Thwaites and <i>Shorea gardneri</i> (Thwaites) P.S.Ashton [Dipterocarpaceae]. Other Orchidaceae species which sharing the same habitat of this new species are <i>Cylindrolobus lindleyi</i> (Thwaites) Ormerod & C.S.Kumar, <i>Bulbophyllum crassifolium</i> Thwaites ex Trimen, <i>B. elegans</i> Gardner ex Thwaites, <i>Pinalia tricolor</i> (Thwaites) Kuntze and <i>Podochilus sp.</i>.</p> <p> With respect to sharing of habitat by different species in this genus, <i>Trichoglottis tenera</i> is widespread in the tropical montane and sub-montane forests at Nuwara-Eliya and Maturata (Nuwara-Eliya District, Central Province), Laggala (Matale District, Central Province), Rangala and Hunnasgiriya (Kandy District, Central Province), and Namunukula (Badulla District, Uva Province) (Jayaweera 1981) 1200 m a.s.l., while, <i>T. longifolia</i> is distributed in sub-montane forests at Aranayaka, (Kegalle District) and Bambarabotuwa, Kuruwita, Palabaddala, Samanala Nature Reserve and adjacent areas of Sinharaja MAB (Man and the Biosphere Reserve) (Ratnapura District) in Sabaragamuwa Province between 910‒1200 m a.s.l. (Bandara <i>et al.</i> 2022) (Fig. 4). <i>Trichoglottis quadriga</i> and <i>T. longifolia</i> can occur in same habitat but, can be easily identified following the field identification key provided in this manuscript.</p> <p> <b>Conservation status:</b> Based on the distribution data, the EOO and AOO were estimated as ~ 47 km 2 and 20 km 2 respectively. So far no threat is known to this species except for the anthropogenic pressure in the habitats, which is inferred to cause a depletion in the quality of habitat for the species. With 5 sub-populations, comprising less than 50 mature individuals <i>Trichoglottis quadriga</i> can be assessed depending on its extremely small population size as Critically Endangered (CR: D) following IUCN guidelines (IUCN 2022).</p> <p> <b>Additional specimens examined:</b> <i>Trichoglottis tenera</i>: <b>— SRI LANKA. NUWARA ELIYA DISTRICT:</b> Nuwara Eliya, Aug. 1962, <i>Jayaweera 2192</i> (PDA!); Hakgala, Mar. 1889, <i>W. Nock s.n</i>. (PDA!); Punduluoya, Feb. 1973, <i>Cramer 4067</i> (US!- <i>US00506216</i>); along road Kandy to Nuwara Eliya, May 1978, <i>D.D. Soejarto 4876</i> (US!- <i>US00506217</i>, L!- <i>L1529312</i>, P!- <i>P00361712</i>); <b>BADULLA DISTRICT</b>: Namunukula, Mar. 1907, <i>J.M. Silva s.n.</i> (PDA!); <b>LOCALITY UNKNOWN</b>: 1829, <i>Macrae 66</i> (K!- <i>K000895724</i>, holotype); <i>Macrae s.n.</i> (K!- <i>K000974382</i>); <i>Macrae s.n.</i> (K!- <i>K000974383</i>); <i>Thwaites C.P.2983</i> (PDA!); <i>Walker 118</i> (PDA!); 1869, <i>Thwaites C.P.2983</i> (P!- <i>P00361710</i>); 1854, <i>Thwaites C.P.2983</i> (P!- <i>P00361711</i>). <b>INDIA.</b> Grands bois à Neddoubitta, Jan. 1841, <i>L. Claude</i> s.n. (P!- <i>P00361713</i>). <i>Trichoglottis longifolia</i>: <b>— SRI LANKA. KEGALLE DISTRICT:</b> Maligakande, Aranayaka, Apr. 2022, <i>AKAG 29.2022</i> (PDA!-spirit); <b>RATNAPURA DISTRICT:</b> Seethagangula, Kuruwita‒Eratne trail, Samanala Nature Reserve, May 2022, <i>AKAG 30.2022</i> (PDA!).</p>Published as part of <i>Bandara, Champika, Atthanagoda, Anusha Gayan, Peiris, Gayan Prasanga, Jayasundara, Ramitha, Ranasinghe, Bhanuka, Kumara, Udayanga Nuwan, Aberathne, Nimantha, Hettiarachchi, Dushantha, Dissanayake, Malith, Karunathilake, Thimira, Bandara, Niwahal Vimukthi, Fernando, Oshan Dewmith, Wijesundara, Chandra Bandara, Bandara, Nadeesha Lewke & Kumar, Pankaj, 2023, Trichoglottis quadriga (Orchidaceae: Epidendroideae: Vandeae: Aeridinae), a new species from Central Highlands of Sri Lanka, pp. 265-272 in Phytotaxa 609 (4)</i> on pages 266-270, DOI: 10.11646/phytotaxa.609.4.2, <a href="http://zenodo.org/record/8297097">http://zenodo.org/record/8297097</a&gt

Exploring the plastic collection and recycling trends in Sri Lanka

This study examined plastic waste management in Sri Lanka, concentrating on the contributing factors to plastic waste generation and collection. Data were gathered through a questionnaire survey from registered plastic recycling and management centres. The analysis revealed a positive correlation between tourist arrivals and plastic waste generation, indicating increased plastic waste production due to tourism spanning from 2014 to 2022. However, plastic waste collection negatively correlated with precipitation levels, suggesting heavy rainfall hampers collection efforts. This study found HDPE, PVC, LDPE, and PP to be the most collected and recycled plastic types, whereas PS and PET recycling were less prevalent. The results demonstrate the need for enhanced recycling infrastructure and highlight the necessity for government participation in plastic waste management initiatives. This study recommends increasing waste collection and recycling during the tourist season. In addition to enhancing public and private awareness, there should be additional investment in recycling facilities. The findings offer crucial insights into plastic waste management in Sri Lanka, emphasizing the importance of collaborative efforts and comprehensive strategies to tackle plastic pollution