FOUR NEW RECORDS FOR THE VASCULAR FLORA OF BANGLADESH

This study records two species of Pteridophytes, viz., Hemionitis cordata Roxb. ex Hook. & Grev. and Ophioglossum nudicaule L.f. of Pteridaceae and Ophioglossaceae, and two species of Angiosperms, viz., Bacopa australis V.C. Souza and Salvia misella Kunth of Plantaginaceae and Lamiaceae, respectively, for the first time in Bangladesh, based on the plant specimens collected during the recent botanical explorations conducted in selected areas of Bagerhat, Barguna, and Cumilla districts. A detailed taxonomic description with key characters, notes on ecology, uses, distribution, distinctness from other similar taxa, representative specimens examined, and photographs of each of these four species have been provided.


Introduction
Bangladesh, as an integrated part of the Indian-Subcontinent Centre of Plant Diversity (Vavilov, 1926) and the South Asian Mega Centre of Genetic Diversity (Chowdhury, 1996), harbours almost all groups of plants in its 148,460 sq. km. area. Within the territory of Bangladesh, a total of around 6,612 species of green plants have so far been recorded, in contrast to the flexible estimate of 11,650 plant species for the country (Khan 1977;Ahmed et al., 2007Ahmed et al., , 2008Ahmed et al., , 2009aSiddiqui et al., 2007;Sarker and Hossain, 2009;Begum et al., 2014;Rahman and Khatun, 2014;Tabassum, 2018;Alfasane et al., 2019;Tabassum et al., 2020;Dong and Haque, 2021;Sultana and Rahman, 2021;Sultana et al., 2022;Jone et al., 2022;http://bforest.portal.gov.bd). Nevertheless, the publication of 329 new records of vascular plants following the report of a total of 3,813 species for the vascular flora of Bangladesh Ahmed et al., 2008Ahmed et al., , 2009a) raises the total number of recorded vascular plant species in this country to around 4,142 (Sultana and Rahman, 2021;Hossain et al., 2022;Rahman et al., 2022;Sultana et al., 2022;. During our botanical explorations conducted in 2019-2022, in different areas of Bagerhat, Barguna and Cumilla districts, including the Sundarbans and Tengragiri Mangrove Forests, many specimens of vascular plants were collected and housed in the Jahangirnagar University Herbarium (JUH). Recently, we found that some of these specimens do not match any known plant species in Bangladesh. After a detailed taxonomic investigation, we identified a few of these specimens belonging to two Pteridophyte species, namely, Hemionitis cordata Roxb. ex Hook. & Grev. of family Pteridaceae and Ophioglossum nudicaule L. f. of Ophioglossaceae, and a few other specimens associated with two Angiosperm species, namely, Bacopa australis V.C. Souza and Salvia misella Kunth of Plantaginaceae and Lamiaceae, respectively. These species have never been reported earlier in any taxonomic literature published so far on the flora of Bangladesh (e.g., Hooker, 1872Hooker, -1897Prain, 1903a, b;Siddiqui et al., 2007;Ahmed et al., 2008Ahmed et al., , 2009aRahman et al., 2015;Haque et al., 2018;Shetu et al., 2018Shetu et al., , 2022Uddin and Hassan, 2018; *Corresponding author, email: gazibotju@gmail.com Hossain et al., 2019Hossain et al., , 2020Hossain et al., , 2021Hossain et al., , 2022Khanam et al., 2020;Roy and Khan, 2020a, b;Khan et al., 2021a, b;Islam et al., 2022). Therefore, these four species have been reported here as the new records of vascular plant species for Bangladesh.

Materials and Methods
The plant specimens of B. australis and H. cordata were collected from Lalmai hill and its adjacent areas in Cumilla district; specimens of O. nudicaule from the coastal areas of Bagerhat (Sundarbans East Wildlife Sanctuary) and Barguna (Tengragiri Eco Park) districts; and those of Salvia misella from Mongla port area of Bagerhat district, during our recent floristic explorations conducted in 2019-2022. The collected specimens were processed, dried, and managed using standard herbarium techniques (Singh and Subramaniam, 2008). These specimens were critically examined in the Plant Systematics and Biodiversity Laboratory of Jahangirnagar University. Their taxonomic identification was confirmed through consulting the experts and taxonomic descriptions and keys available in the relevant literature (Hooker, 1885;Prain, 1903a, b;Li and Hedge, 1994;Stevens et al., 2001;Hammel et al., 2003Hammel et al., -2014Cui et al., 2004;Mirza, 2007a, b;Khanam, 2009;Rahman, 2009;Gangmin et al., 2013;Xianchun et al., 2013;Sosa et al., 2018), matching with the relevant voucher specimens of the Jahangirnagar University Herbarium (JUH) and Bangladesh National Herbarium (DACB), and digital images of the respective voucher specimens available on the websites of different international herbaria, including Herbarium of Royal Botanic Gardens (K) and Muséum National d'Histoire Naturelle (P).

Results and Discussion
Sporophytic stage: October to February.
Ecology: On the shady place of the hill slope.
Uses: This plant is used as an ornamental herb in shade houses.
Distribution: This species is native to Cambodia, China, India, Indonesia, Laos, Malaya, Myanmar, the Philippines, Sri Lanka, Taiwan, and Viet Nam (POWO, 2023). In Bangladesh, this species is recorded in the Lalmai Hill area of the Cumilla district. As Bangladesh belongs to the historical native range of the Indian subcontinent, this species is most probably native to this country.
Sporophytic stage: July to November. Ecology: Moist sand and clay soils in shady habitats.
Flowering and fruiting: June to December. Ecology: On mud in ditches and paddy fields. Uses: The stems and leaves of this species are eaten by wildlife.

Salvia misella
Flowering and fruiting: November to February. Ecology: Found to grow along the roadside in moist and semi-shady habitats.
Uses: This species is considered a weed in Tropical America (Richardson and Keng, 2010  In Bangladesh, four species of Salvia L., viz., S. coccinea Juss. ex Murr, S. leucantha Cav., S. plebeia R.Br., and S. splendens Sellow ex Rome & Schult., have been reported so far (Khanam, 2009). S. misella is clearly distinct from S. splendens by its deltoid, sparsely pubescent leaves, deep green calyx, and 5-6 mm long corolla, in contrast to S. splendens's ovate, glabrous leaves, red calyx, and 4.5 cm long corolla. S. misella is a herb with a green calyx, while S. leucantha is a subshrub with a purple calyx. S. misella differs from S. coccinea's campanulate and deep red or scarlet, 2 cm long corolla by its tubular, purple, 5-6 mm long corolla. S. misella is different from S. plebeia by its deltoid ovate leaves and bluish-purple corolla, in contrast to S. plebeia's ellipticlanceolate leaves and white corolla.