Acrostichum aureum

Probably the only fern species found in the mangroves of Sri Lanka*. It occurs usually on landward side of the mangroves and brackish water marshes. Young reddish leaves edible and made into a curry. Dried leaves are also used as thatching of temporary huts.

* Locality unknown single specimen of Acrostichum speciosum is also mentioned in the Revised Handbook to the Flora of Ceylon Vol XV Part B page 367.

කරවිල/බටු කරවිල[Karawila/Batu karawila](Momordica charantia)

An indigenous climbing herb occurs in lowland rain forests, riverine forests and cultivated areas up to 1200 m a.s.l. Fruit use in curries and pickles. Several cultivated varieties are used as vegetables.

Areca triandra

Native palm of Bangladesh, Andaman islands and Malay peninsula. Cultivated as an ornamental in gardens. 

ඉත්ත[Itha](Schefflera heterobotrya)

An endemic shrub or tree occurs in up country forests from 610 to 1900 m elevations. Sometimes found near streams. Flowering and fruiting occurs after the monsoon with full fruiting from October.

රත් කෑලිය/කොස්බඩ[Rat-keliya/Kosbada](Litsea ligustrina [Syn: Litsea longifolia/Litsea quinqueflora])

Common native tree occurs in the wet zone forest understory up to about 2000 m altitude. Bark use in medicine.

නස් නාරන්[Nus naran] (Citrus x madurensis)

Shrub or small tree cultivated in home gardens for its edible fruit. It is probably a stable hybrid between Kumquat (Fortunella spp.) and sour Mandarin species (Citrus reticulata var. austera) 

Restricted Demon (Notocrypta curvifascia)

Rare butterfly found in wet and intermediate zone jungles. Its larva feeds on Zingiber zerumbet, Zingiber officinale, Meistera trichostachya, Hellenia speciosa, and Meistera fulviceps.

වැරණිය[Veraniya](Hedyotis fruticosa)

An indigenous small shrub grows on open secondary vegetation and rocky areas on mountain tops up to about 1000 m elevations

Woodland false buttonweed (Spermacoce remota [Syn: Spermacoce assurgens])

Introduced annual herb native to tropical America. Naturalized along roadsides and waste places. 

Didymoplexis pallens

Rare terrestrial, leafless and saprophytic orchid species grows under shade of trees in carpet of fallen and decaying leaves of the wet lowland forests.

Wormbush/Pinkroot(Spigelia anthelmia)

An introduced annual herb native to tropical America. Naturalized along roadsides, home gardens and waste places in Southern and western part of the Country.

බැවිල[Bavila]/Heart Leaf Fan Petals(Sida cordata)

Common indigenous prostrate or ascending slender herb grows in grasslands, waste areas and roadsides, mainly in the dry lowlands. Whole plant used in Ayurveda medicine.

Thyas coronata

Location - Sri Jayawardenapura, Kotte.
Host Plant - Flowers (Only first instar larvae) and tender leaves (Larvae of all instars) of Rangoon creeper/Drunken sailor(Quisqualis indica) - (Sujeeva Gunasena, ‎ Personal communication, October 31, 2015)
External Links - http://www.inaturalist.org/observations/1890501

කටු තම්පලා[Katu tampala]/Spiny amaranth/Prickly amaranth (Amaranthus spinosus)

Very common introduced weed occurs along roadsides, waste and disturbed grounds and in gardens. Flowering throughout the year. The young leaves are eaten as a kind of spinach and whole plant especially leaves and roots are medicinal.

මිදි ගස්/මහ මිදි/හීන් මිදි/වල්-වෙල්-මිදි [Midi Gas/Maha Midi/Heen Mii/Wal-Wel-Midi]/Headache Tree(Premna serratifolia [Syn: Premna obtusifolia/Premna divaricata])

An indigenous shrub or tree common in coastal areas and mangroves. Flowering from December to March and August to September. Fruits black when ripe. Leaves and roots used in medicine and wood in constructions  industry.

ගස් දුම්මැල්ල/කයිල/වැල් කයිල [Gas dummella/Kaila/Wel Kayila] (Phyllanthus reticulatus)

Common indigenous shrub or small tree occurs in secondary vegetation from sea level to 1000 m altitude. Bark, roots, stem, leaves and fruits are used in medicine.

ගොඩ කිරිල්ල[Goda Kirilla]/Indian Elm (Holoptelea integrifolia)

Native tree occurs in dry lowland forests. Flowering from March to April and fruiting from April to June. Wood heavy and strong. 

Asystasia intrusa

An introduced herb native to Malaysia. It occurs in lightly shaded locations, especially in the hill country, probably escaped from gardens. 

Erebus ephesperis [Nyctipao crepuscularis]

Expanse - 8-10 cm

Reference - The Lepidoptera of Ceylon - F. Moore, F.Z.S. Vol 3 Page 148.

External Links -  http://www.inaturalist.org/listed_taxa/3589369

Sonerila rhombifolia

Rather rare endemic erect herb occurs in Southwestern wet lowland forests. Sonerila rhombifolia grows sympatrically with the Sonerila silvatica.