Xylosma longifolia

Xylosma longifolia, generally known as longleaf logwood,^[6] is a species of flowering plant in the family Salicaceae, endemically distributed throughout South, East, and Southeast Asia, spanning over many countries.

Xylosma longifolia is an evergreen shrub or tree, typically reaching 4–7 m (13–23 ft) in height. Its gray-brown bark is scented, and the trunk may bear simple or branched spines, though they vary. Branchlets are glabrous, often armed with axillary spines, and exhibit sympodial growth. The leaves are simple, alternate, and stipule-absent, with a short petiole measuring 5–8 mm (0.20–0.31 in) and a leathery lamina measuring 4–15 cm (1.6–5.9 in) by 2.5–5 cm (0.98–1.97 in). Leaf shape varies from narrowly elliptic, oblong-elliptic, oblong-lanceolate, to narrowly obovate, but are typically lanceolate, featuring an acute, cuneate, or rarely obtuse base, serrate margins, and an acuminate apex with a 1–2 cm (0.39–0.79 in) acumen. Lateral veins number 6–11 pairs, prominently raised on both surfaces. Flowers are unisexual, hypogynous, bracteate, and greenish, measuring 2.5–3.5 mm (0.098–0.138 in) in diameter. They are borne in short racemes or reduced panicles, either singly or in condensed clusters within leaf axils. The rachis is 0.5–2 cm (0.20–0.79 in) long, glabrous or puberulous. Pedicels are slender, puberulous, and 1–2 mm (0.039–0.079 in) long. Bracts are ovate in staminate flowers and lanceolate in pistillate flowers, measure 0.5–1 mm (0.020–0.039 in), and glabrous or sparsely puberulous. Sepals, numbering 4–5, are persistent, ovate or lanceolate, 1–2 mm (0.039–0.079 in), glabrous or sparsely puberulous abaxially, entirely glabrous adaxially, with entire to erose margins. Petals are absent in both male and female flowers. Staminate flowers feature minute, 0.3 mm (0.012 in), ellipsoid, dorsifixed anthers and a glandular disk with small, connate glands. Pistillate flowers possess an annular or few-lobed disk, an ovoid superior ovary, measuring roughly 2 mm (0.079 in) with 2–3 placentas, each bearing 2–3 ovules. Styles, numbering 2–3, are very short, measuring 0.5–0.8 mm (0.020–0.031 in) or less and may be partly or completely joined. The fruit is a globose, dry berry, 4–6 mm (0.16–0.24 in) in diameter, glabrous, and crustaceous, enclosed in a thin sheath without dark streaks. Initially red when ripe, it dries to black, with the persistent calyx, disk, and style remaining attached. Fruiting pedicels are slender, 3–4 mm (0.12–0.16 in) long. Seeds, numbering 4–5, are brown, measure roughly 4 mm (0.16 in) long, ovoid, and flattened on one or more sides due to mutual compression. Flowering occurs from April to May, with fruiting from June to October.^[7][8][9]

Xylosma longifolia occurs across a broad range, encompassing much of Asia, with its endemic range including China, Hong Kong, India, Indonesia, Laos, Myanmar, Nepal, Pakistan, Thailand, and Vietnam. Within China, it is found in Fujian, Guangdong, Guangxi, Guizhou, Hainan, and Yunnan. In Pakistan, it occurs in Murree, Pakistani Punjab, Mirpur, and Kotli, while in India, its distribution extends through Andhra Pradesh, Arunachal Pradesh, Assam, Haryana, Himachal Pradesh, Jammu and Kashmir, Jharkhand, Manipur, Meghalaya, Odisha, Punjab, Tamil Nadu, Tripura, Uttarakhand, and West Bengal. The species is also recorded in Myanmar in Mandalay and Sagaing. Though not explicitly documented as introduced outside its native range, Xylosma longifolia has been sighted in the United States.^[10][11]

Xylosma longifolia is found in moist subtropical and mountain forests, typically at elevations ranging from 600–1,600 m (2,000–5,200 ft), often thriving in ravines. It primarily relies on entomophily, though cleistogamy and allogamy also occur. Seed dispersal is facilitated through autochory, zoochory, and anthropochory.^[7][9]

Xylosma longifolia was first described by Nathaniel Wallich in 1845 as Flacourtia ferox, although it used a different type specimen. The original taxon was superseded in 1857 by Dominique Clos with Xylosma longifolium.^[8][12] This naming was later changed to its current name via William T. Stearn when he considered the genus to be feminine rather than neuter, though this is still disputed.^[13][14] Over time, the species has gathered approximately 12 synonyms.^{[Note 1]}

Historically, Xylosma longifolia was placed in Flacourtiaceae under older classification systems such as those of Cronquist and Takhtajan. Eventually, Flacourtiaceae, including this taxon, were reclassified into Salicaceae, a placement adopted by the APG III system and subsequently recognized by Plants of the World Online, though this classification remains disputed.^[15][16][17]

Due to its wide geographic distribution, Xylosma longifolia is known by numerous common names across different regions. In India alone, names vary by language and locale; notably known by chirundi, dandal, dieng-kani, godya, katari, kataponial, kandhara, mota-koli, nongleishang, katpatra, pansra, phalama, and sialu. In China, it is commonly called cháng yè zhà mù (Chinese: 長葉柞木) or cháng yè zuò mù (Chinese: 长叶柞木), while in Pakistan it is known as batti. In English, the plant is referred to as long-leaved xylosma or longleaf logwood.^[6][9]

The genus name Xylosma derives from the Greek words xylon, meaning "wood," and osme, meaning "fragrance," referring to the aromatic wood found in some species. The species epithet longifolia means "long-leaved", in reference to the length of the foliage of this species.^[18][19]

Xylosma longifolia is a significant ethnomedicinal plant widely used in northeastern India, particularly in Assam and Manipur. Both its leaves and stem bark are valued in traditional medicine for treating numerous ailments, including liver disorders, jaundice, piles, dysentery, gastritis, stomach pain, kidney stones, coughs, acne, scabies, ringworm, dizziness, restlessness, insomnia, anxiety, muscular sprains, and skin infections. It is also employed to eliminate lice and ticks, and even used by some communities in brewing beer. The plant exhibits notable pharmacological properties such as antispasmodic, antioxidant, antifungal, antidermatophytic, and antitubercular effects. Tribal communities prepare decoctions, extracts, or topical applications from boiled leaves and bark depending on the condition being treated. Phytochemical screening of methanol extracts has revealed a rich profile of bioactive compounds, including alkaloids, flavonoids, phenols, tannins, terpenoids, and saponins. Spectroscopic and chromatographic analyses confirmed the presence of multiple functional groups and a variety of major and minor compounds. These findings underscore the therapeutic potential of the plant and point to the need for further research to isolate and develop novel drugs from its phytoconstituents.^[9][20]

Xylosma longifolia is broadly distributed with a stable and plentiful population. It currently faces no significant threats, and none are projected in the near future. Accordingly, it is listed LC by the IUCN Red List, though further research is needed to strengthen and expand upon this assessment.^[1]

• Media related to Xylosma longifolia at Wikimedia Commons
• Data related to Xylosma longifolia at Wikispecies