Black Rajah (Charaxes solon cerynthus)

Rather uncommon butterfly flies throughout the year of all climatic zones. But it is much common below 650 m elevations, especially in the dry zone forests. It is less common in the intermediate zone and rare in the wet zone. In the dry zone its main flight season is start of the northeast monsoons in October and in other zones it is before the arrival of southwest monsoon in April. Black Rajah is a butterfly of forest canopy though it is often seen on animal droppings. Hill-topping phenomena is observed of male Black Rajahs*. Its larva feeds on leaves of Tamarindus indica (Tamarind/Indian Date/සියඹලා) and Croton tiglium (ජයපාල). The larva is active during the night.  

* Male flying up to and staying on a hill top waiting for females.

Ceylon Treebrown (Lethe daretis)

A rather common endemic butterfly restricted to hill country forests above 1500 m a.s.l. It flies all the year round though much common from March to April. Its larva feeds probably on leaves of  a bamboo species (Sinarundinaria debilis) occurs at the higher elevations (Only egg laying observed so far) 

Beak/Lobed Beak (Libythea laius lepitoides)

Rare butterfly distributed in same areas and similar habitats as it is of rather similar Club Beak. Its behavior is also similar to that of the Club Beak. Early stages of its life cycle is not yet recorded in Sri Lanka, though it is believed that Beak larva also feeds on the leaves of Celtis philippensis [මැදිතැල්ල] and Celtis timorensis [ගූරැන්ද/බූරැන්ද] as it is with the Club Beak.

Great Crow/King Crow (Euploea phaenareta corus)

Rather uncommon butterfly flies in well wooded coastal wetlands and mangroves of southwestern part of the country from Negombo to Galle. Further inland it can be also found in Sinharaja forest reserve near Kudawa, Kanneliya forest reserve and Kottawa forest reserve. Great Crow is a shade loving insect spends much of its time resting on leaves or twigs of forest trees while flies only hour or two after sunrise. Its larva feed on leaves of Cerbera odollam (ගොන් කඳුරු) trees. 

Joker (Byblia ilithyia)

Rare butterfly restricted to the scrub lands of northwestern coast from Chilaw to Jaffna.  Ormiston recorded of seeing numbers settled on a small bush at Palatupana of Hambantota district in 1909. But neither him nor anyone else met it there since. Its larva feeds on leaves of Tragia plukenetii (වැල් කහඹිලියා)

Southern Duffer (Discophora lepida)

Rather rare butterfly of southwestern wet lowland rain forests with bamboo undergrowth. It flies at dawn and dusk. Larva feeds on Ochlandra stridula [Bamboo/බට] leaves.

Blue Glassy Tiger (Ideopsis similis exprompta)

Rather common butterfly restricted to the southwestern coast from Negombo to Galle, not occurring inland more than 32 km s. Blue Glassy Tiger especially flies in mangrove and marsh habitats. However it can be also observed in inland wet lowland forests such as Sinharaja, Morapitiya-Runakandha and Kanneliya. Larva feeds on Vincetoxicum indicum (බිං නුග), Vincetoxicum flexuosum var. tenuis,  and Anodendron paniculatum leaves (Ovipositing also observed on Parsonsia alboflavescens [කිරි අඟුණ/වල් අඟුණ] though larvae refused to feed on them when given in the lab).

          Major N. Manders while considering the restricted distribution of this butterfly doubted that it may be an accidentally introduced species to the island from the China via Galle harbor. Before completion of the breakwater at Colombo, Galle was the first port in the island and introduction of this butterfly may have been occured during that period (Manders N., 1904) As per Manders distribution of this insect at that time was "...coast and twenty miles or so inland, that is to say, the foothills extending from Galle in the south to about ten miles beyond Colombo on the north." 

Manders N., 1904 Butterflies of Ceylon, The Journal of the Bombay Natural History Society V. 16 (1904-1906)

Dark Blue Tiger (Tirumala septentrionis)

Dark Blue Tiger is a common butterfly flies mainly in the dry zone of the country up to 1000 m elevations. It takes part in migrations. Larva feeds on Dragia volubilis (අගුණ) leaves in the field and also on 

Heterostemma tanjorense when offered.

Tawny Rajah (Charaxes psaphon)

Rather uncommon butterfly flies all over the island except in the higher hills. It is much common in the dry zone especially during the south-west monsoon and scarce in the wet zone. Both sexes especially males settle on wet patches, bird droppings, decaying animal matters and rotting fruits. It is a very fast flier and also take part in migrations. Hill-topping phenomena is also observed of male Tawny Rajas*. According to the sources females are rarely seen, since they are less active and preferring to sit deep in the foliage. Larva feeds on Entada zeylanica, Tamarindus indica (සියඹලා/Tamarind/Indian Date), Dalbergia pseudo-sissoo (බඹර වැල්),  Entada rheedei (පුස් වැල්) and Croton laccifer (ගස්-කැප්පෙටියා). Egg laying observed on Miliusa tomentosa and  Actinodaphne stenophylla (නික දවුල) and larva fed on Aglaia elaeagnoidea when offered in the lab.

* Male flying up to and staying on a hill top waiting for females.

Lemon Pansy (Junonia lemonias vaisya)

Common butterfly flies everywhere up to about 2000 ft. It is very common in the dry zone and local and scarce in the wet zone. It takes part in migrations. Larva feeds on Barleria prionitis (කටු කරඬු/Yellow Hedge Barleria),  Hygrophila auriculata (ක‍ටු ඉකිරි/නීරමුල්ලිය), Lindernia rotundifolia, Dyschoriste madurensis, Dyschoriste nagchana, Rungia repens (සුළු නයි/Creeping rungia), Ruellia prostrata (නිල් පුරුක්)  and Barleria lupulina (රන්වන් කටු කරඩු).

Tamil Treebrown (Lethe drypetis)

Rather uncommon butterfly  inhabiting hill country forests with bamboo undergrowth. Larva feeds on Bambusa multiplex, Bambusa vulgaris, Davidsea attenuata(බට) and Dendrocalamus giganteus.

Gaudy Baron/Elahera Butterfly(Euthalia lubentina psittacus)

Rather uncommon butterfly though widely distributed throughout the island in all climatic zones from sea level to about 1500 m altitude. Both males and females settle on wet earth to absorb minerals and feeds on rotten fruits (which is unusual since in most other butterflies it is only males do mud puddling.) Woodhouse* remarks that it is also known as the Elehera (ඇලහැර) among 'Kandy collectors'  since it is always found in that area during March and September. Larva feeds on varies පිළිල species such as Dendrophthoe falcata, Macrosolen capitellatus, Taxillus incanus, Taxillus tomentosus, Taxillus cuneatus and Tolypanthus gardneri of the family Loranthaceae

* Woodhouse L.G.O. (1950) The Butterfly Fauna of Ceylon, Ceylon Government Press, Colombo, 2nd (Abriged) Edition.  1950.

Common Lascar (Pantoporia hordonia sinuata)

Locally common butterfly flies in wet and intermediate zone from lowlands to about 1400 m elevations. It has a slow flight which somewhat resemble to the flight of a dragonfly which too has similar colors (i.e. Variegated Flutterer). Larva feeds on leaves of Senegalia caesia (හිඟුරු-වැල්), Albizia chinensis (කබල් මාර/හුලං මාර) and Acacia pennata (ගොඩ හිඟුරු). As per Ormiston* it is especially common in May and June.

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* Ormiston  W. (1924) The Butterflies of Ceylon, H.W.Cave & Co., Colombo 1924, AES Reprint New Delhi, 2003

Blue Pansy (Junonia orithya patenas)

An uncommon butterfly occurs all over the island. But abundant in moderate elevations from 2000 to 4000 ft. It inhabits open areas such as grasslands, pathways, etc. In such habitats it can be encountered usually on the ground resting with wings open. When alarm it flies fast for a short distant to settle again. Larva feeds on leaves of Justicia procumbens (මයානි/Common small justicia), Yamazakia pusilla, and Rungia repens (සුළු නයි/Creeping rungia).  Its larva also fed on Centranthera indica (දුටු සතුටු) when offered. 

Sri Lankan Tiger/Monarch (Parantica taprobana)

Sri Lankan Tiger is an endemic butterfly Occurs above 1000 m elevation and common above 1200 m though occasionally found as low as 800 m elevation. It inhabits forests and well wooded hill country home gardens. Larva feeds on Ceropegia elegans, Cynanchum alatum and Vincetoxicum iphisia. Larva also fed on Vincetoxicum bracteatum when offered in the lab and egg laying was observed on Vincetoxicum cordifolium.

Double Branded Crow (Euploea sylvester montana)

An uncommon butterfly though widely distributed in most parts of the island from lowlands to about 1000m a.s.l. It takes part in migrations. Its larval host plants are Gymnema sylvestre (මස් බැද්ද) and Gymnema lactiferum of the family Apocynaceae. 

Tamil Bushbrown (Mycalesis subdita)

Tamil Bushbrown is an endemic butterfly occurs in scrublands, home gardens and grasslands in dry and intermediate zones below 750m elevation. It is fond of rotting fruits. Larva feeds on Ischaemum timorense in the field and fed on Panicum maximum(Guinea Grass/රට තණ) and Axonopus compressus (Carpet Grass/පොටු තණ) in the lab when offered.

Jewel Four-ring (Ypthima singala)

Rather rare butterfly flies all the year round mainly in the Uva patanas from 500 -1500m elevations. Sightings also available from Galaha, Elpitiya, Haldummulla and Watawala. Larval host plant is not known though egg laying was observed in a unidentified grass species and larva has been successfully reared on Carpet grass/පොටු තණකොළ (Axonopus compressus) (van der Poorten, G. and van der Poorten, N. 2012)

References:
van der Poorten, G. and N. van der Poorten, 2012. New and revised descriptions of the immature stages of some butterflies in Sri Lanka and their larval food plants (Lepidoptera: Nymphalidae). Part 2: Subfamily Satyrinae. Tropical Lepidoptera, 22: 80–92.

Baronet (Symphaedra nais)

Rather rare butterfly with local distribution in south-central and south-eastern part of the country from Haldummulla to Batticola and there to Trincomalee. Larva feeds on කඩුම්බේරිය(Diospyros melanoxylon) 
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Small Leopard (Phalanta alcippe ceylonica)

"So far it has only appeared in one valley in the Nitre Cave, surrounded by 6000 feet hills, except towards the north-west and east, where it faces the Bintenna country. The butterflies are found from 2000 to 4000 feet. Principal appearance, May-June. A few at end of the year." - (Mackwood to Ormiston in Ormiston W., 1924)

"I owe my specimens to Mr. MAckwood's generosity. He tells me that it was fairly plentiful at Nitre Cave in May and June, 1918" (Ormiston W., 1924)

"A very local butterfly which can be taken from 2 to 4 thousand feet for most months of the year, but in numbers, from March to May, below Corbet's Gap (near Madugoda), surrounded by 6000 feet hills. It has also been taken, but very rarely, in the Ratnapura District." - (Woodhouse L.G.O., 1950)

"It is by no means common, occurring at elevations of between 1800 and 4500 feet, .......In the four years I spent observing and collecting butterflies in this country, I can only ever remember seeing this butterfly on two occasions; both times in the hills around Kandy, and both times it was travelling very fast, and stopping just long enough to be recognized." (d' Abrera Bernard, 1998)

Small Leopard is a forest dwelling, critically endangered butterfly with local distribution. It appears from March to June months of the year in the hills, primarily in the Knuckles range. Above photograph was also taken in Knuckles range, on the road to Meemure village from Corbet's Gap, near Karambakatiya oya on 17th August 2014. Its only known larval host plant is Rinorea decora.

References:

d' Abrera Bernard, 1998 The Butterflies of Ceylon, WHT Publications : Colombo.

Ormiston  W., 1924 The Butterflies of Ceylon, H.W.Cave & Co., Colombo 1924, AES Reprint New Delhi, 2003

Woodhouse L.G.O., 1950 The Butterfly Fauna of Ceylon, Ceylon Government Press, Colombo, 2nd (Abridged) Edition.  1950.