Sri Lanka’s location, historic and geologic isolation from the continental landmass, topography and climate act to shape its biogeography and biodiversity, including conferring a remarkably high level of endemism, given its close proximity to the mainland.
The island hosts several ‘point endemic1 species and even monotypic endemic genera. However this irreplaceable biodiversity is now under severe threat because of extensive anthropogenic landuse changes that began over two centuries ago, under colonial rule, and continues to this present date. Due to high levels of endemism, extensive loss
and degradation of natural ecosystem, Sri Lanka has been identified as one of the 36 global biodiversity hotspots.
A pocket guide to the Butterflies of Sri Lanka covers all the butterfly species known to date from Sri Lanka aiming of providing field identification features of adult butterflies. Almost all the species are provided with color photographs (very few with colored drawings) depicting their sexual dimorphism, seasonal forms etc. while providing distribution maps and key identification characters & behaviors. Further it contained the names of selected larval food plants for each butterfly species.
A recent (2013) taxonomic review of the freshwater-fish genus Rasboroides, which is endemic to Sri Lanka, showed it to comprise four species: R. vaterifloris, R. nigro- marginatus, R. pallidus and R. rohani. Here, using an integrative-taxonomic analysis of morphometry, meristics and mitochondrial DNA sequences of cytochrome b (cytb) and cytochrome oxidase subunit 1 (coi), we show that R. nigromarginatus is a synonym of R. vaterifloris, and that R. rohani is a synonym of R. pallidus. The creation and recognition of unnecessary taxa (‘taxonomic inflation’) was in this case a result of selective sampling confounded by a disregard of allometry. The population referred to R. rohani in the Walawe river basin represents an undocumented trans-basin translocation of R. pallidus, and a translocation into the Mahaweli river of R. vaterifloris, documented to have occurred ca 1980, in fact involves R. pallidus. A shared haplotype suggests the latter introduction was likely made from the Bentara river basin and not from the Kelani, as claimed. To stabilize the taxonomy of these fishes, the two valid species, R. vaterifloris and R. pallidus, are diagnosed and redescribed, and their distributions delineated. We draw attention to the wasteful diversion of conservation resources to populations resulting from undocumented translocations and to taxa resulting from taxonomic inflation. We argue against translocations except where mandated by a conservation emergency, and even then, only when supported by accurate documentation.
The following three new species of Trypetheliaceae are described from Sri Lanka: Astrothelium inspersoconicum, A. isohypocrellinum, and Polymeridium fernandoi. Ten species are newly recorded from Sri Lanka: Astrothelium flavoduplex, A. galligenum, A. scoria, A. straminicolor, Constrictolumina planorbis, C. porospora, Dictyomeridium proponens, Marcelaria cumingii, Polymeridium jordanii, and Pseudopyrenula media.
The taxonomy of the three native taxa assigned to the genus Labeo (L. dussumieri, L. fisheri and L. porcellus lankae) in Sri Lanka is reviewed. The population hitherto identified as L. dussumieri in Sri Lanka is shown to be a distinct species, here named L. heladiva. Labeo heladiva, new species, has a wide distribution in the low and mid-elevations of the island and is distinguished from its Indian congeners by the combination of having two pairs of barbels; 12-13 branched dorsal-fin rays; lateral line with 44-51 scales; ½8-½9+1+6-7 scales in transverse series; and 19-22 circumpeduncular scales. It differs from its closest relative, L. dussumieri, principally by having 44-51 vs. 50-60 lateral-line scales, 19-22 vs. 22-27 circumpeduncular scales, and by uncorrected pairwise genetic distances of 1.27-2.22% and 1.88-2.91% for the two mi-tochondrial genes COI and cytb, respectively. Labeo fisheri, which is endemic to the upper reaches of the Mahaweli River basin in the Knuckles mountain range and the central hills in the vicinity of Kandy, is distinguished from Indian congeners by having (in combination) only a single pair of barbels; dorsal fin with 10-12 branched rays; lateral line with 37-39 scales; 7+1+4½-6 scales in transverse series; and 17-20 circumpeduncular scales. Labeo lankae is recognized as a valid species endemic to Sri Lanka. Long suspected to have become extinct, or known only from spurious records, an extant population is reported from the northern dry zone of the island. Labeo lankae is the sister species of L. porcellus of pen-insular India; it can be distinguished from its congeners by having, in combination, 10-12 branched dorsal-fin rays; 36-39 lateral-line scales; ½8+1+5-6½ scales in transverse series; and 21-24 circumpeduncular scales. It differs from L. por-cellus principally by having ½8 (vs. ½6-½7) scales between the origin of the dorsal fin and the lateral line, 21-24 (vs. 20-21) circumpeduncular scales and uncorrected pairwise genetic distances of 1.27% and 1.41% for the mitochondrial genes COI and cytb, respectively. The three species of Labeo in Sri Lanka do not form a monophyletic group.
The monotypic genus Lankanectes, considered an evolutionary long branch with India's Nyctibatrachus as its sister lineage, is represented by L. corrugatus, a species widely distributed within the wet zone of Sri Lanka up to 1500 m asl, where it inhabits a variety of lotic and lentic habitats. Here, following an integrative taxonomic approach using DNA-based phyloge-nies, morphology, morphometry, and ecological niche models, we describe a new species-Lankanectes pera sp. nov. The new species is distinguished from its sister species mainly by its tuberculated throat and absence of dark patches on venter, throat, manus and pes. The uncorrected genetic distances between the two Lankanectes species for a fragment of the non-coding mitochondrial 16S rRNA gene is 3.5-3.7%. The new species has a very restricted climatic distribution with a total predicted area of only 360 km 2 (vs. 14,120 km 2 for L. corrugatus). Unlike L. corrugatus, which prefers muddy substrates and marshy areas, the new species is observed inhabiting only pristine streams flowing through canopy covered montane forests in the highest reaches of the Knuckles Mountain range. The specialized new species will need immediate conservation attention due to its restricted distribution (montane isolate), specialized habit of inhabiting clear mountain streams, and small population size.
The earliest information on Sri Lankan echinoid species belonging to the Irregularia dates back to Alexander Agassiz (1872). However, the current knowledge of diversity and distribution of irregular echinoids from Sri Lanka (formerly Ceylon) remains sparse. In addition, there are no recent taxonomic studies or biodiversity surveys for irregular echinoids, and no illustrated field-guides or reference collections are available specifically for Sri Lanka. To address these gaps, left open for more than 100 years since the work of Clark (1915), this study was conducted as an island-wide systematic sampling survey. Over 200 echinoid specimens were collected from 24 localities in Sri Lankan coastal waters by snorkelling and SCUBA diving down to 33 m depth. The collected specimens were identified using existing keys and authenticated with specimens available at the Natural History Museum in Vienna, Austria. The present study records 22 irregular echinoid species belonging to 15 genera and nine families in four orders. Among the identified irregular echinoids, six species, Echinocyamus megapetalus H.L. Clark, 1914, Fibularia ovulum Lamarck, 1816, Fibulariella angulipora Mortensen, 1948, Echinodiscus cf. truncatus L. Agassiz, 1841, Peronella oblonga Mortensen, 1948 and Brissus cf. agassizii Döderlein, 1885, are new records for Sri Lanka. Four unidentified, possibly new species belonging to the genera Fibularia, Jacksonaster and Metalia are reported, but kept in open nomenclature until more material becomes available. At present, the diversity of irregular echinoids from Sri Lanka now stands at 37 species representing 11 families in four orders. A dichotomous key is presented for all Sri Lankan irregular echinoids.
Recent finds of Leightoniella zeylanensis, classified variously in the Collemataceae and Pannariaceae, enabled us to generate DNA sequence data for investigating its phylogenetic affiliation. Newly generated sequence data from the internal transcribed spacer (ITS) region and the large subunit of the nuclear ribosomal DNA (nrLSU), the small subunit of the mitochondrial ribosomal (mrSSU) DNA, and the largest subunit of the RNA polymerase II gene (RPB1) indicate that L. zeylanensis is a member of the Pannariaceae, belonging to a strongly supported clade together with Physma, Lepidocollema, and Gibbosporina (= the ‘Physma clade’). With the currently available data, however, relationships within this clade are largely impossible to reconstruct with confidence. L. zeylanensis was found to possess ellipsoid ascospores surrounded by a thick, gelatinous perispore with pointed ends, supporting a previously published hypothesis that such a perispore type is an synapomorphy for the Physma clade.
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Zootaxa 4422 (4): 478-492 Abstract Schistura scripta, new species, is described from Nakiyadeniya in the southwestern lowlands of Sri Lanka. It can be distinguished from all other congeners from Sri Lankan and peninsular India by the combination of the following characters: an incomplete lateral line with 53-76 pores, ending beneath the dorsal-fin base or slightly beyond; 7-13 post-dorsal bars; 7½ branched dorsal-fin rays; absence of an axillary pelvic lobe; and absence of a suborbital flap.