Diversity of Moths in two Different Habitat Types of the Wet Zone of Sri Lanka

Moths (Insecta: Lepidoptera) of Sri Lanka have not been well studied despite the country being a global biodiversity hotspot. It is known that the moth communities are declining worldwide due to threats such as loss and fragmentation of habitats, urbanisation, light pollution, invasive species, and climate change. Thus, tropical moth assemblages that contribute towards ecosystem functions including pollination should be studied and conserved. The present study was carried out in Indikadamukalana Forest Reserve (IMFR) and in Wattala, an urban habitat, both in Western Province to investigate the moth species diversity, richness, relative abundance and habitat parameters that can affect moth assemblages. Moth diversity was investigated over a 7-month period from February to October 2018. Transect line count method was used to sample diurnal moths and light traps with white reflective sheets were used to study nocturnal moths. Aerial nets and fruit baited traps were also used. A total of 160 species belonging to 20 families which represent 8.37% of the 1,911 moth species recorded from Sri Lanka were recorded from both habitats with IMFR recording 138 species belonging to 19 families and urban habitat recording 26 species belonging to 12 families. The species richness and abundance of moths were highest at IMFR. Least species richness and abundance of moths were recorded from the urban habitat. Family Crambidae was the most specious and dominant group throughout the study period followed by family Erebidae which could be due to habitat strata occupied by the moth groups whereas Families Pterophoridae and Tortricidae were recorded with the least number of individuals at IMFR and urban habitats respectively. At IMFR highest abundance of moths were recorded in May while in the urban habitat it was August. The climate parameters between the two habitats did not depict a significant difference but relative humidity was observed to have the highest impact on the changes in abundance of moths with ambient temperature having the least. This study has provided a baseline for future studies into moths of lowland wet zone forests and has highlighted the importance of natural forests in the maintenance of moths in the country. The diversity observed between the habitats were mainly due to anthropogenic activities and could be most probably due to the presence of host plants, evolutionary adaptations and weather parameters. The study recommends, establishing a scientific database on moth diversity, host plants and other factors of the moth life cycle.Keywords: Moths, Wet zone, Sri Lank

Diversity and Habitat Preferences of Moths (Insecta: Lepidoptera) in Indikadamukalana, a Lowland Wet Zone Forest in Sri Lanka

The moths (Insecta, Lepidoptera) of Sri Lanka have not been well studied and no comprehensive scientific study on their diversity has been carried out over the past 100 years. Thus, establishing species richness and diversity of moths in different habitats of the island is important. The present study was carried out to investigate moth species diversity and habitat factors which can affect moths in Indikadamukalana Forest Reserve situated in the wet zone of Sri Lanka. Moth diversity of the forest was investigated for a period of approximately seven months in 2018, where two habitat types as forest edge and within forest were studied. Transect line count method was used to sample diurnal moths and light traps were used to study nocturnal moths. Aerial nets and fruit-baited traps were used to improve the sampling efficiency. Weather parameters of the two habitat types were estimated using a potable weather station. A total of 138 moth species of 19 families were recorded, with forest edge habitat recording 18 families (91 species) and within the forest habitat recording 15 families (47 species). Crambidae and Erebidae were the most prominent families of moths found in both habitats of the forest. Gelechiidae was recorded only from within the forest habitat while Sphingidae, Hepialidae, Tortricidae and Bombycidae were recorded only from the forest edge habitat.  Weather parameters between the two habitats did not depict a significant difference. Maintenance of Sri Lanka’s biodiversity hotspot status lies within the wet zone of the country. Thus, long term studies of moth communities of the wet zone are of vital importanc

The Current Status of the Tiger Beetle Species of the Coastal Habitats of Sri Lanka

The species of tiger beetles inhabiting coastal habitats of Sri Lanka have not been studied for nearly three decades. We report the tiger beetle species currently occupying the coastal habitats of the island, their distribution, microhabitats and habitat preferences. Species and distributions reported nearly three decades from similar previous studies are also recorded. Southern, North-Western and Western coastal belts (n=22) of Sri Lanka were investigated for the presence of tiger beetles. Three species, Hypaetha biramosa, Lophyra (Lophyra) catena, Myriochila (Monelica) fastidiosa, were recorded from eleven locations. M. (Monelica) fastidiosa was reported for the first time, in a single location of the Southern coastal belt. Habitat parameters of the locations and the length of the body and mandible between H. biramosa and L. (Lophyra) catena, were statistically compared to determine specific habitat preferences of the two species. Analysis of Variance using Minitab 16.0 revealed that H. biramosa occupy habitats with high solar radiation (438-1023 w/m2) and soil salinity (0.0-0.1ppt) while L. (Lophyra) catena occupy habitats with low solar radiation (132-402) and non-saline soils (0.0 ppt). Similar length of mandibles of these two species indicated that habitat selection of the species was not based on prey utilization, but may depend on the intensity of solar radiation and the level of soil salinity of the locations

Bat Guano; A Resource or a Contaminant?

Bat guano which consists of urine and feces of bats is known to be the vitality source inside a cave ecosystem. Nevertheless, commensal as well as pathogenic microorganisms that inhabit the gut of the bats might also get released into the environment via bat guano. The tested hypothesis was that there is a microbial contamination due to the release of bat guano into a water body. In the present study “Waulpane” cave was selected since it houses the largest bat roost in Sri Lanka and a freshwater stream (Halwinnedola) that flows through the cave covering the cave floor throughout the entire year. Main objective of this study was to investigate the fecal and total coliform bacteria along with total viable bacteria (TVB) and pathogenic Salmonella spp. and Shigella spp. Water and fecal samples were taken times from 29th April to 29th September 2019. Two sites were selected other than the site (site 1-100 m ahead of the cave mouth, site 2-100 m inside from the cave mouth, site 3-100 m after the cave exit) inside the cave to compare the variations of releasing bat guano into the freshwater stream. Detection and enumeration of pathogenic bacteria Salmonella spp. and Shigella spp., fecal and total coliform bacteria and TVB in the samples were done following the standard protocols. Tukey comparison of one-way ANOVA with a 95% confidence interval (CI) in Minitab 17 software application package was used to distinguish any changes in the TVB count among the selected sites. The most intriguing finding was the contamination of both site 1 and 2 by Salmonella spp. Since bats are known to be potential reservoir and host for Salmonella spp. and the first Salmonella spp. occurrence in bats was recorded in the rectal swab of the fruit bats (Rousettus leschenaulti) in Sri Lanka, it was evident that the key contaminating source is bat guano. Clearly, as the results portray, dispensation of bat guano has elevated the degree of contamination of fecal coliforms in the water because higher amount of fecal coliform colonies were detected in site 2. There were no significant differences in the TVB counts among the sites. Nonetheless, significantly higher TVB counts were recorded from the fecal samples. This study proves the microbial contamination specifically Salmonella spp. by the release of bat guano into a freshwater body for the first time in Sri Lanka and the contamination of the water critically create environmental and health issues when the downstream water is used for agriculture drinking and other domestic consumption.Keywords: Bat guano, Salmonella spp., Fecal coliform bacteria, Total coliform bacteri

Butterfly Assemblages in Two Different Habitats in Lowland Wet Zone, Sri Lanka

Tropical butterflies should be studied as targets of conservation as they contribute towards maintenance of ecosystem functions including pollination. This study investigated butterfly assemblages of different habitats of the Western Province in Colombo district in Avissawella region. Seethawaka Wet Zone Botanical Garden (SWBG) lies adjacent to the Indikada Mukalana Forest Reserve (IMFR). In SWBG, a disturbed forest habitat (DFH) and a buffer zone habitat (BZH) which was located between the SWBG and the IMFR were selected as two different habitats. In both, 100m length fixed transects were established and all butterfly species within 10m x 10m x 100 m box were recorded from July to November 2016. Aerial nets and fruit baited traps were also used to sample butterflies. Shannon-Wiener diversity indices, evenness, species richness and relative abundance of butterflies were calculated for both habitats. A total of 62 butterfly species (6 endemic species and 15 endemic sub species) belonging to 6 families were recorded from the study. All six endemics are found in the DFH and only three were found in BZH. Species richness of two different habitats was equal (49 species) where higher abundance of butterflies (386 individuals) was in the DFH. BZH had 270 individuals. Shannon-Wiener diversity index and the evenness were highest in the BZH (3.3109, 0.8507) than the DFH (2.7943, 0.7179). Nymphalidae was the most abundant family throughout the study period whereas Family Riodinidae had the least number of individuals in both habitats. The data showed the presence of 25.1% of the butterflies of Sri Lanka and 32.1% of the lowland wet zone butterflies. Some belonged to Near Threatened and Vulnerable categories of conservation with the Ceylon Rose (Pachliopta jophon) being endangered and the Philippine Swift (Caltoris philippina) being Critically Endangered. Assemblages of butterflies recorded exhibit a range of feeding strategies (plant feeders, fruit feeders etc.) and depend on a wide range of host plants found in these habitats. The DFH is part of the highly visited SWBG. This study demonstrates the contribution made by a botanical garden originally established to conserve and display plants, to conservation of a major group of Sri Lankan invertebrates.Keywords: Butterfly assemblages, Lowland wet zone, Endangered, Critically endangered, SriLank

New distributional record of Cylindera (Oligoma) paradoxa (W. Horn, 1892) (Coleoptera: Cicindelidae) in Ratnapura District, Sri Lanka

Since the 19th century, Cylindera (Oligoma) paradoxa (W. Horn, 1892) has been recorded from only 10 locations in Sri Lanka, with only 2 of those recorded in the past 30 years. We recently found this species in the Keeragala estate (Ratnapura District) during field surveys. Our new record fills a gap in the knowledge of this species’ distribution in Sri Lanka

Chromium Induced Histological Changes in the Body Wall of the Earthworm Eudrillus eugeniae

In Sri Lanka, documented evidence indicates that the Chromium (Cr) content in water andsoil is high, reaching upto 0.60 mgl-1 in water and 103 mg kg-1 in soil and sediment. Cr is oneof the most toxic heavy metals, which is capable of inducing adverse effects in exposedorganisms even in trace amounts. Of the two valency states, Cr3+ and Cr6+, the latter ispotentially more toxic than the former. In the present study we examined the histologicalalterations in the body wall of Eudrillus eugeniae, a commonly occurring species ofearthworm, exposed to hexa-valent Cr.Adult earthworms were collected from a culture facility in Talawakalle, and acclimatized fortwo weeks. Worms with a well-developed clitellum and of 0.29 + 0.009 g weight were usedfor standard chronic exposure trials of 28 days. For the trials, the animals were placed insuitably prepared clay pots containing banana piths soaked in five different concentrations(0.002 – 20 mg l-1) of Cr6+. At the end of the 28 days, the worms were fixed in Zenkerfixative, washed, dehydrated, embedded in paraffin wax and the tissue sections taken at7 μmwere stained using hematoxylin-eosin. Histological alterations in the outer epithelium werethen recorded in detail.It was evident that Cr6+ induced alterations in the outer epithelium of the earthworm at all testlevels. A reduction in the thickness of the epithelium was noted (Control – 61.6 ± 6.1μm,0.02 mg l-1 – 28.0 ± 1.5 μm). Another observation was the reduction in the number of nuclei(Control – 31.3 ± 2.8, 0.02 mg l-1 - 7.4 ± 0.4) and the increase in the number of pyknoticnuclei in a given area of epithelial tissue (Control - 2.3 ± 0.4, 0.002 mg l-1 - 10.5 ± 1.0).Epithelial cells were neatly compacted with distinct cell margins in earthworms that were notexposed, whilst those exposed showed disintegration of cell margins even at 0.002 mg l-1 ofCr6+. Mucous cells, which are generally apparent, were not distinct in Cr6+ treated worms.Epithelial sloughing was more pronounced in treated earthworms than in the controls. Thespace between the epidermis and muscle layers were greater in treated worms than in thecontrols (Control - 0.7 ± 0.5 μm, 0.02 mg l-1 - 23.6 ± 1.0 μm). The muscle layers of the bodywall of the Cr6+ treated worms showed loss of structural integrity and increased intercellularspaces with the damage being more severe in those exposed to 20 mg l-1. This study providesevidence that histopathological alterations are possible in the earthworm at levels of Crrecorded in Sri Lanka’s natural ecosystems.

Habitat Selection in Dung Beetles (Family Scrabaeidae; Subfamily Scarabaeinae) in the Wasgomuwa National Park

A study was carried out to investigate habitat selection of dung beetles in terms of bothhabitat and dung types. The present study was considered necessary as information on theecology of dung beetles in the dry zone of Sri Lanka is lacking. A total of 125 pitfall trapswere set in five habitat types (dry-mixed evergreen forest, riverine forest, stream/river banks,scrubland and grassland) and using five types of mammalian dung (leopard, ungulate,elephant, bear and buffalo) as baits. The pitfall traps were laid in the morning and kept openfor 24 hrs. A two-way ANOVA was conducted to discern significant differences betweenspecies richness and abundance of dung beetles across habitats and dung types.A total of 455 individuals belonging to 22 species and 7 genera were recorded from the pitfalltraps. This included one endemic species. Significant differences in species richness wasapparent (P<0.05;F=3.34) between the different habitat types with the highest number ofspecies of dung beetles in the riverine habitat (20 species) and the lowest in stream/river bankhabitats (8 species). No significant differences were recorded with respect to abundanceacross the habitat types. However there was a trend that, from among the five habitats, thestream/river banks showed highest abundance whilst the scrubland had the lowest abundance.Considering preferences of dung types, significant differences were apparent for both speciesrichness (P<0.05; F=4.09) and abundance (P<0.05; F= 0.02). The highest species richnesswas supported by leopard dung (19 species) whilst the lowest number of species (11 speciesin each) was observed in both bear and ungulate dung. Highest abundance of dung beetleswas on bear dung whilst the lowest was on ungulate dung. Moreover some species wererestricted only to a few habitats or dung types (Onthophagus cervus only in riverine habitatand Onthophagus quedentatus only in buffalo dung).This study has for the first time revealed habitat and dung preferences among dung beetles inthe dry zone Sri Lanka. Such information would be essential for the maintenance of a healthypopulation of dung beetles, which in turn would benefit natural ecosystems because of theirinvaluable ecological services.

The Maghreb – one more important biodiversity hot spot for tiger beetle fauna (Coleoptera, Carabidae, Cicindelinae) in the Mediterranean region

The tiger beetle fauna of the Maghreb region is one of the richest in the Palaearctic, including 22 species and 5 subspecies and 19% of all Palaearctic species of Cicindelinae. Assembled by their chorotypes, the Maghreb tiger beetles fall into eight different groups that include Maghreb endemics (26% of fauna), Mediterranean (7%), West Mediterranean (40%), North African (4%), Mediterranean-Westturanian (4%), West Palaearctic (4%), Afrotropico-Indo-Mediterranean (4%), and Saharian (11%) species. The Mediterranean Sclerophyl and Atlas Steppe are the Maghreb biogeographical provinces with the highest species richness, while the Sahara Desert has the lowest Cicindelinae diversity. Twenty-five cicindelid species and subspecies (93% of Maghreb fauna) are restricted to only one or two habitat types in lowland areas. Only Calomera littoralis littoralis and Lophyra flexuosa flexuosa are recognized as eurytopic species and occur in three types of habitat. The highest tiger beetle diversity characterizes salt marshes and river banks (in both cases 11 species and subspecies or 41% of Maghreb fauna). Approximately 85% of all Maghreb tiger beetle species and subspecies are found in habitats potentially endangered by human activity

Morphology and Morphometrics of Egg Masses of Fall Armyworm, Spodoptera frugiperda (Lepidoptera, Noctuidea) in Sri Lanka

Morphological and morphometric studies on the life cycle stages of a species, specifically the egg stage, provide a sufficient guide in identifying the species from its initial stage. This study was aimed at egg mass characterisation of The Fall Armyworm (Spodoptera frugiperda) (FAW); an economically important pest worldwide. Eggs were reared in the laboratory and measurements such as the position of the egg mass, colour, shape, arrangement, number of egg masses per plant and clutch size were obtained. A total of 36 egg masses were studied. Spherical shaped, cream coloured eggs were deposited very closely like a string of beads in flat, single or double layered masses. Majority of the egg masses (72.2%) were single layered. Eggs were firmly attached to the leaf with a sticky substance. Most of the egg masses were found on the underside of Maize leaf blades which is a well-known adaptation of most insect herbivores like lepidopterans. Egg masses were covered with hair-like strands which can be attributed as a mechanism to avoid desiccation. However, 47.22% of the egg masses were partially covered with hairs while only 11.11% of the egg masses were covered fully which also included all egg masses obtained from field.The presence of ridges and transverse lines in eggs were noticeable Noctuid characters in eggs. A considerable variation was observed in number of egg masses laid by a female and its clutch size, which are measures of fitness of adult females. The clutch size varied from 9-200 eggs with an average of 73 eggs but varied from 100-500 eggs in field conditions in previous records. Newly hatched females depositedlarger number of eggs but the older females deposited few or no eggs. Thus, the age of the adults also affected their fecundity. The average diameter of an egg was 0.43 mm and the egg stage duration varied with temperature and humidity of the external environment such as having 3-5 days under laboratory conditions. This study provides a baseline for future studies of this pest moth identification and characterisation using morphological and morphometric measurements of the egg stages. The study recommends, sensitising farmers and making them aware of life history characteristics of FAW, thus early detection can be led to early eradication of this pest species, before the emergence of the highly destructive larval stage. Keywords: Spodoptera frugiperda, Fall Armyworm, Egg mass, Morphometrics, Sri Lank