Saturday, August 5, 2017

Lowland Hump-nosed Pit Viper (Hypnale zara)

English: lowland Hump-nosed Pit Viper
Binomial: Hypnale zara
Sinhala: පහතරට මූකලන් තෙලිස්සා

Hypnale zara is a venomous pitviper species endemic to Sri Lanka. Based on the taxonomic revisions done so far, have stated that there are four species that belong to the genus Hypnale which live in Sri Lanka (Including possibly new species Hypnale sp. ‘amal’). Among them, population of H. zara has been restricted to the forests of lowlands and the foothills of the central highlands and no observations have been recorded in anthropogenic habitats (Maduwage et al. 2009). At a glance, morphologically all these four species look similar. But with a closer look, H. zara can be easily distinguished from its congeners using attributes like mentioned in the above named photographs. This species is more active at night and in the day time they live under the logs, rocks and in the leaf litter. 
Venom of this genus mainly causes local envenoming, coagulopathy, acute renal failure and death. A research done by Dr. Anjana Silva and others (Silva et al. 2012) to compare the in-vivo toxicity of venoms of this genus reveals that the venom of H. zara is less toxic compared to the venom of H. hypnale and has a higher LD50 value compared to H. nepa with the LD50 value of 6 μg protein/g. A report authored by Dr. Kalana Maduwage(Maduwage et al. 2011) describes a fatal case of a 47 years old male due to coagulopthy and acute kidney failure followed by envenoming of H. zara. 
Even it is common to seen in lowland forests, deforestations might be the main threat for the species and protecting the remaining fragments of lowland forests will guarantee the future existence of the species.

References: 
  • Silva, Anjana, Panduka Gunawardena, Danister Weilgama, Kalana Maduwage, and Indika Gawarammana 2012 Comparative in-Vivo Toxicity of Venoms from South Asian Hump-Nosed Pit Vipers (Viperidae: Crotalinae: Hypnale). BMC Research Notes 5(1): 471.
  • Maduwage, Kalana, Anjana Silva, Kelum Manamendra-Arachchi, and Rohan Pethiyagoda 2009 A Taxonomic Revision of the South Asian Hump-Nosed Pit Vipers (Squamata: Viperidae: Hypnale). Zootaxa 2232: 1–28.
  • Maduwage K, Kularatne K, Wazil A, Gawarammana I: Coagulopthy, acute kidney injury and death following Hypnale zara envenoming – The first case report from Sri Lanka. Toxicon 2011, 58:641–643.

Thursday, June 8, 2017

Black ruby barb (Pethia nigrofasciata)

English: Black ruby barb
Binomial: Pethia nigrofasciata
Sinhala: බුලත් හපයා/මනමාලයා

Black ruby barb is an endemic species of freshwater fishes found in lowland wet zone of the Southern and Western region of Sri Lanka. They live in clear and un polluted water streams. It is in the category of 'Least Concern' in the IUCN Red list. But it is a popular species in the aquarium trade and necessary actions have to be taken to save the species in the natural habitats.

Saturday, June 3, 2017

Knuckles Shrub Frog (Pseudophilautus fulvus)



English: Knuckles Shrub Frog
Binomial: Pseudophilautus fulvus
Sinhala: දුම්බර පඳුරු මැඩියා

Pseudophilautus fulvus is an endemic species of shrub frogs restricted to the Knuckles mountain region. It has been observed in closed canopy forests, anthropogenic habitats, secondary forests and cardamom plantations(Meegaskumbura and Manamendra-Arachchi 2005).
Above photographed ones were observed in the adjoining forest of Deanston Conservation Center in the knuckles region. The major threats for the species are habitat destruction and agro-chemical pollution. IUCN Red List status of the frog is ‘Endangered’

References: 
  • Manamendra-Arachchi, K., and Pethiyagoda, R. (2005). ''The Sri Lankan shrub-frogs of the genus Philautus Gistel, 1848 (Ranidae: Rhacophorinae), with description of 27 new species.'' Raffles Bulletin of Zoology, Supplement 12, 163-303.
  • The IUCN Red List of Threatened Species(tm) 2015-4 - http://www.iucnredlist.org
  • Manamendra-Arachchi, K. & R. Pethiyagoda (2006): Sri Lankan amphibians [in Sinhala]. – WHT Publications, Colombo.

Monday, May 1, 2017

Black-lined Golden Rasbora (Rasboroides nigromarginatus)

Male
Female
Male



English: Black-lined Golden Rasbora
Binomial: Rasboroides nigromarginatus
Sinhala: කළු වරල් හල්මල් දණ්ඩියා[Kalu waral halmal dandiya]

Rasboroides nigromarginatus is a relatively rare endemic species of freshwater fish restricted to the Kalu river basin. This species was described for the first time by a Germen biologist named H. Meinken in 1957 after observing a single specimen of the fish among some exported ornamental fresh water fishes from Sri Lanka. Since the exact collected location has not been known, he has mentioned ‘Ceylon’ as the locality. Meanwhile, the species remained in the synonymy of R. vaterifloris for a long time. It has not been observed in the natural environment since then until R. Pethiyagoda & K. Manamendra Arachchi observed some fish from Athwelthota area in 1994 that match with the H. Meinken’s first description. Again in 2010, members of Wildlife Conservation Society, Galle have found and observed the same fish from Athwelthota area and have re-described the fish as a valid species by verifying Meinken’s work(Batuwita S. et al., 2013). 
Above photographed ones were also observed in river Maguru, which is a branch of Kalu river. Observed place was a shady place of the river margin close to the borders of Sinharaja forest. Place was away from human habitats and no activities were observed that cause environmental pollution, which might be the reason to have a healthy living population of this rare fish. Since the population of the fish is restricted to few locations, critical actions need to be taken to protect the species for the future. 

Reference: 
  • Batuwita S., de Silva M. and Edrisinghe U., 2013. A review of the danionine genera Rasboroides and Horadandia (Pisces: Cyprinidae), with description of a new species from Sri Lanka Ichthyol. Exploe. Freshwaters, Vol. 24, No. 2, 121-140 pp.

Saturday, March 11, 2017

Pastilla ruhuna


Binomial Name: Pastilla ruhuna

Pastilla ruhuna Ng & Tay, 2001 is an endemic species of freshwater crabs belongs to the monotypic genus of Pastilla. Population of this species is restricted to the southeastern wet zone of Sri Lanka. Also they live in burrows dug by them in the wet soil. According to IUCN Red list, it is in the category of ‘Endangered’ and conservation actions have to be taken to guarantee the future existence of this rare species.

Referances:
  • The IUCN Red List of Threatened Species(tm) 2015-4 - http://www.iucnredlist.org
  • Identification guide provided by - Sameera Akmeemana

Sunday, February 26, 2017

Mittermeier's shrub frog (Pseudophilautus mittermeieri)

English: Mittermeier's shrub frog
Binomial: Pseudophilautus mittermeieri
Sinhala: මිටර්මයර්ගේ පඳුරු මැඩියා

Mittermeier's shrub frog is an endemic species of shrub frogs restricted to the lowland wet zone of Sri Lanka. According to the original description, they have been observed in Kottawa and Beraliya Forest, in Elpitiya at the elevation levels of 60m and 150m. This species is morphologically more similar to Pseudophilautus decoris and phylogenetic analysis also shows that they are more related. But the population of P. decoris has been restricted to the Rakwana mountains with a higher elevation level compared to the habitat of Pseudophilautus mittermeieri(Meegaskumbura and Manamendra-Arachchi 2005). 
Above photographed ones were observed in Gilimale and Makandawa (Kithulgala) wet zone rain forests that fall in to the same elevation range(60m-150m). They were observed on shrubs of the closed forest. IUCN red list status of the species is endangered (EN).

Referances:
  • Meegaskumbura, Madhava, and Kelum Manamendra-Arachchi 2005 Description of Eight New Species of Shrub Frogs (Ranidae: Rhacophorinae: Philautus) from Sri Lanka. The Raffles Bulletin of Zoology 12: 305–338.
  • The IUCN Red List of Threatened Species(tm) 2015-4 - http://www.iucnredlist.org
  • Manamendra-Arachchi, K. & R. Pethiyagoda (2006): Sri Lankan amphibians [in Sinhala]. – WHT Publications, Colombo

Saturday, February 18, 2017

Angraecum zeylanicum



Angraecum zeylanicum is a wild orchid found on tree trunks of lowland wet zone of Sri Lanka.