Journal
of Threatened Taxa | www.threatenedtaxa.org | 26 November 2020 | 12(15):
17121–17128
ISSN 0974-7907 (Online) | ISSN 0974-7893 (Print)
doi: https://doi.org/10.11609/jott.6238.12.15.17121-17128
#6238 | Received 28 May 2020 | Final received 08
September 2020 | Finally accepted 12 October 2020
Diversity of scorpions (Arachnida: Scorpiones)
in Polonnaruwa Archaeological Reserve, Sri Lanka
Kumudu B. Wijesooriya 1,
Lakshani S. Weerasekara
2 & Kithsiri
B. Ranawana 3
1 Department of Zoology, Faculty of Science, Eastern
University, Vantharamoolai 30376, Sri Lanka.
2 Department of Zoology, Faculty of Science, Eastern
University, Sri Lanka.
3 Department of Zoology, Faculty of Science, University
of Peradeniya, Sri Lanka.
1 kbwije.uop@gmail.com (corresponding author), 2 lakshaniw@esn.ac.lk,
3 kithsiri.r@gmail.com
Editor: Neelesh Dahanukar, Indian
Institutes of Science Education and Research (IISER), Pune, India. Date of
publication: 26 November 2020 (online & print)
Citation: Wijesooriya, K.B., L.S. Weerasekara & K.B. Ranawana (2020). Diversity of
scorpions (Arachnida: Scorpiones) in Polonnaruwa Archaeological Reserve, Sri Lanka. Journal of
Threatened Taxa 12(15): 17121–17128. https://doi.org/10.11609/jott.6238.12.15.17121-17128
Copyright: © Wijesooriya et al. 2020. Creative
Commons Attribution 4.0 International License.
JoTT allows unrestricted use, reproduction,
and distribution of this article in any medium by providing adequate credit to
the author(s) and the source of publication.
Funding: Self-funded.
Competing interests: The authors declare no competing interests.
Author details: Kumudu B. Wijesooriya is an enthusiastic undergraduate majoring in
Zoology and his research interests extend to population ecology, animal
behavior, systematics and taxonomy. Lakshani S. Weerasekara, BSc is a
young graduate major in Zoology and her research interests extend to ecology
and wildlife conservation, animal behavior and primatology. Kithsiri B. Ranawana, PhD is a renowned ecologists in Sri Lanka and an
active naturalist. His research interests include ecology and conservation.
Author contribution: KBW did the field work and prepared the manuscript,
LSW did the statistical analysis and prepared the manuscript and KBR prepared
the manuscript.
Acknowledgements: We convey our deepest gratitude to Mr. T.G.S. Gamage,
project manager, Alahana Project, Polonnaruwa
and Mr. Sajith Wijesooriya, curator, Alahana Project, Polonnaruwa for
granting the permission to carry out the research in archaeological reserve in Polonnaruwa, Mr. Hiranya Sudasinghe for reviewing the first draft, Mr. Diluk Malshan for creating the
site map, Ms. Devmi Gamage for identifying the
geomorphology of the site and Mr. Shaveen Britto, Mr.
Sandun Bandara and Mr. Vilochana Bandara for assisting
in statistical analysis. We also thank
the two anonymous reviewers and editors for their productive comments and
suggestions.
Abstract: Sri Lanka harbours 20 scorpion species belonging to
four families, of which 15 are endemic.
The distribution and ecology of scorpion fauna in Sri Lanka is poorly
known. In this study, we surveyed the
diversity of scorpions in the Polonnaruwa
Archaeological Reserve in the dry zone of Sri Lanka. Microhabitats were thoroughly observed using
the direct visual encounter method and UV lights from July to November 2018 for
about seven hours (19.00–02.00 h) by two to three observers. Species, abundance, age/sex, and microhabitat
features were recorded. Diversity
indices, including α-diversity and β-diversity, were calculated. Heterometrus swammerdami
was the most abundant species recorded, while Isometrus
thwaitesi was the rarest. Reddyanus
loebli and R. besucheti
were common in both open and forest habitat types. Charmus laneus was recorded for the first time in Polonnaruwa. The
highest Shannon Index and Margalef Diversity Index
values were recorded in open habitats, but species evenness was low compared to
forest habitats. Sørensen
index values showed a 58% species similarity between two habitats. The results presented here contribute to the
knowledge of the diversity of scorpions in these historically significant
sites. This can serve as a basis for
future research on the impact of habitat modification and fragmentation on populations,
distribution and ecology of scorpions.
Keywords: Buthidae, diversity, dry
zone, microhabitat, Scorpionidae.
INTRODUCTION
Sri Lanka supports a high level of biodiversity, and
hence Sri Lanka together with Western Ghats of India is considered a global
biodiversity hotspot (Mayer 2000;
Mittermeier et al. 2011). Most of the biodiversity research in Sri
Lanka concerns charismatic, flagship fauna (Fernando et al. 2011; Nijman 2012; Kittle et al.
2017), paying less attention to small
sized and enigmatic species.
Invertebrates are among the poorly investigated taxa. A few published work available for
butterflies (van der Poorten
& van der Poorten 2016), bees (Karunaratne & Edirisinghe
2008), dragonflies (Bedjanič 2004), theraphosid spiders (Samarawckrama et al. 2005), land snails (Naggs et al. 2005) and freshwater crabs (Bahir et al. 2005) represent significant attempts to characterize
little-known invertebrate fauna (Ranawana et al. 2013). Among invertebrate
taxa, studies of scorpions have gained attention owing to their economic (Kularatne et al. 2015) and ecological importance. Recently, Kovařík et al. (2016, 2018, 2019) summarized 20 known scorpion species of Sri Lanka
belonging to four families: Buthidae (13 species), Scorpionidae (five species) Hormuridae
(one species), and Chaerilidae (one species), of
which 15 species (75%) are endemic to the island.
The spatial distribution of scorpions is influenced by
a range of climatic and environmental variables such as temperature, rainfall,
elevation, slope, soil properties, vegetation type and land cover (Polis 1990; Prendini 2005). Sri Lanka has
distinct types of habitats, including rain forest, dry mixed evergreen forest,
montane forest, and shrub forest, which support scorpions (Ashton et al. 1997). Most scorpion
species are distributed through the dry zone, and few are found in the wet zone
of Sri Lanka (Kovařík
et al. 2016).
The objective of this study was to assess the diversity of scorpions in
an archaeological reserve located in the ancient city of Polonnaruwa,
in North-central Province, Sri Lanka, as a conservation initiative for
scorpions. Additionally, the study aimed
to provide important information on population structure (age/sex ratio), microhabitat
preference, and community-level characteristics (species richness and diversity
in two selected habitats). Since Polonnaruwa is a well-preserved historic site and tourist
attraction, this study is relevant to the impact of tourism on the conservation
of biological diversity.
MATERIALS AND METHOD
Study site
This study was carried out in the archaeological
reserve in Polonnaruwa ancient city (7.9584N &
81.0027E) located in North-central Province, Sri Lanka, from early July to late
November 2018. The selected study site
with an area of 7.9km2 was an isolated secondary forest patch
consisting ancient monuments dating back to King Parakramabahu
in the 12th Century, and surrounded by human settlements. We have divided the study area into two habitat
types: open habitat and secondary forest (Image 1). Open habitat predominantly consists of
ancient monuments maintained by the Central Cultural Fund, Sri Lanka, with
scattered trees. Some parts of the open
habitat encompass exposed bedrock with boulders, and the soil type is sand to
gravel particle-sized soil with low/no leaf litter (Image 2a). Secondary forest habitat consists of a dry
mixed evergreen forest dominating by Cassia marginata
(Fabaceae), Manilkara hexandra
(Sapotaceae), Drypetes
sepiaria (Putranjivaceae),
and Ficus sp. (Fabaceae),
tree species (Abeynayake et al. 1993) and
scattered amidst shrubs and herbs (Image 2b).
Survey
A pilot study was carried for two days in early July
for habitat selection and species identification before the survey. All possible microhabitats, including both
terrestrial and arboreal, were thoroughly observed using the direct visual
encounter method with the aid of UV lights.
Sampling was carried out by two to three observers and lasted for about
seven hours (19.00–02.00 h). A total of
78 human hours were spent equally for open and forest habitats (39 human hours
per each habitat). Abundance and age-sex
classes were recorded as male, female, or juvenile. But burrowing scorpions were not classified
into age/sex categories due to difficulties in excavating their burrows and
habitat disruptions. Tree barks were
observed up to 3m in height from the ground level. Tree heights were categorized into five
height classes as 1: 0–60 cm, 2: 61–120 cm, 3: 121–180 cm, 4: 181–240 cm and 5:
241–300 cm. Tree diameter at breast
height (DBH) was measured using a DBH tape.
Tree DBH measures were categorized into five classes as 1: 0–120 cm, 2:
121–240 cm, 3: 241–360 cm, 4: 361–480 cm and 5: 481–600 cm. Photographs were taken using a Canon 750D
camera with Canon EF 100mm f/2.8L Macro IS USM lens with an external
flashlight. Identifications of the
species were based on Kovařík et al. (2016).
Statistical
analysis
The α-diversity of scorpion species across open and
forest habitat was calculated using the Shannon diversity index (H’) separately
for two habitats (Magurran 1988). Shannon evenness (E) was calculated to
analyse the evenness of species across the forest and open habitats (Magurran 1988). Margalef’s species richness index (DMg)
was used to compare species richness across microhabitats (Magurran
1988). Bootstrap sampling using the
means of each data set was carried out to assess 95% confidence intervals of
Shannon Index (H’), Shannon Evenness (E) and Margalef
Diversity Index (DMg) using R version 6.3.
The β-diversity, which represents unshared species,
was measured by finding similarity or overlap between scorpion species
composition across microhabitats, using Sørensen
index. We employed chi-squared tests of independence to test the significant
difference in the microhabitat preference (height and DBH) of scorpions between
open and forest habitat types.
RESULTS
During the survey, five species of scorpions belonging
to four genera in two families were recorded (Image 3). Of which, 28% of individuals belonged to
family Buthidae, and 72% of individuals belonged to
family Scorpionidae (Table 1). Observed four species of scorpions were
terrestrial, and only one species, Reddyanus
loebli, was arboreal. Heterometrus
swammerdami (271 individuals) was abundant across
the archaeological site, but its distribution was only confined to the open
habitat. Charmus
laneus was the second most abundant species (37
individuals) in open habitat. Reddyanus loebli (45
individuals) was the most abundant species in forest habitat. The least abundant species of the open and
forest habitats were Reddyanus besucheti (nine individuals) and Isometrus
thwaitesi (three individuals), respectively.
The highest number of individuals was recorded in open
habitat (327 individuals) compared to forest habitat (52 individuals). Highest Shannon index (H’) was recorded in
open habitat but, species evenness was low compared to the forest habitat. Sørensen index was
0.5882 (or 58.82%), where Reddyanus loebli and R. besucheti
were the common species recorded from both habitats (Table 2).
Tree height and DBH preference of arboreal R. loebli were varied. The highest occurrence height was recorded as
300 cm in a Manilkara hexandra
tree, whereas the lowest occurrence height was 15 cm in a Drypetes
sepiaria tree.
Importantly, the highest number of individuals was recorded in height
class 3, while the lowest number of individuals was recorded in height class 5
(Figure 1a). The average DBH was
recorded as 330cm. The highest number of
individuals was recorded in DBH class 4, whereas, at least was recorded in DBH
class 2 (Figure 1b). However, there was no significant difference among tree
height preference and habitats (χ2= 2.947, DF = 4, p= 0.5667). Nevertheless,
there was a significant difference in DBH preference and habitat type (χ2= 18.041, DF = 4, p= 0.0012).
DISCUSSION
The equatorial location of Sri
Lanka and the complex topography of the island produce several distinct
climatic zones and diversified habitats.
The dry zone (60% of the island), intermediate zone (15%), and the wet
zone (25%) are the major climatic zones.
Though climatic and environmental factors and vegetation vary among
these climatic zones, scorpion species are not confined to specific zones (Kovařík
et al. 2016). Their distributions overlap, and only a few
species are restricted to specific habitats, like Hottentotta
tamulus from Jaffna peninsula, Sri Lanka (Ranawana
et al. 2013). We recorded five species, of which four are
endemic to Sri Lanka. In the present
study, Heterometrus swammerdami
was the most abundant species, whereas Isometrus
thwaitesi was the rarest. Reddyanus
loebli and R. besucheti
are the only two species sharing both habitat types. Importantly, Charmus
laneus was recorded for the first time in Polonnaruwa.
Heterometrus swammerdami was the only burrowing species
in this study. They prefer to burrow in termite mounds, though they are not
constructing burrows. They displayed sit
and wait behaviour expecting possible prey with extended pedipalp and open
chela. Most of the time, one adult can
be seen in the opening of the termite mound burrow, and sometimes several
juveniles can be observed with their mother.
Due to their burrowing behaviour it is difficult to observe them closely
to determine age and sex. Higher
opportunities to access resources might account for their higher
abundance. Isometrus
thwaitesi is known as an arboreal species. Kovařík et al. (2016) found I. thwaitesi running on branches and trunks of
trees, and also sitting on leaves 1–4 m in height. In this study, however, all three individuals
were observed on the ground near a wood debris pile among leaf litter, and they
were only observed in forest habitat.
The presence of a higher stratum in the forest habitat compared to open
habitat could be influencing scorpion abundance by providing better foraging
areas where moonlight cannot reach easily (Nime
et al. 2013).
Reddyanus loebli
is a
tree-dwelling species. Most dry zone
trees have fissured barks as an adaptation for harsh weather conditions, and
this gives a suitable microhabitat. They
were mostly (93.2%) observed in Manilkara hexandra, Drypetes sepiaria, and Ficus
sp. trees among and under the scales, within the cracks in the
bark. Most of the observed individuals
displayed sit and wait behaviour under the scales of the tree bark, with
extended pedipalp and open chela, remaining 6.8% individuals observed in brick
walls of ruins. All juvenile individuals
were observed in forest habitat. Vegetation
cover in the forest provides a safe habitat from predators for these
tree-dwelling scorpions. Reddyanus besucheti
is a terrestrial species that is also found in both habitats. In the forest habitat, 55.6% of individuals
were observed on the leaf litter, whereas 44.4% were observed in open habitat
on sand.
Charmus laneus
was the
second most abundant scorpion species observed only in the open habitat. Lourenço (2002)
recorded this species from Mannar District and in Wilpattu National Park (Northwestern
part of Sri Lanka) and Kovařík et al. (2016) recorded this species from Puttalam District and Eluwankulama
(western part of Sri Lanka). Therefore,
this is the first record of C. laneus
from the Polonnaruwa District (eastern part of
the island), which is about 200km away from Mannar
District. Their distribution was
confined to the surrounding of exposed bedrock in an open area. Unlike H. swammerdami,
they were very active and observed running among small grasses near to
exposed bedrock on open land. None of
the individuals was observed in the open grassy plains or among leaf litter.
The total Shannon diversity
index was calculated as 1.0880 for both open and forest habitat. Since the
normal range of the Shannon index is 1.5–3.5 (Magurran
1988), this value for the entire site indicates shallow species diversity
compared to other taxa. This low alpha
diversity is common among predators like scorpions because they are well known
for their restricted movement, cannibalism, predation by nocturnal predators,
habitat specificity, food size specificity, extreme climate adaptability, and
adaptive radiation (Newlands
1972; Polis 1990; Pande et al. 2004). Together with a longer life span than many
invertebrates, these factors may act as constraining factors as far as species
diversity is a concern (Pande et al. 2012). Since, the 95% confidence
intervals of Shannon index values are not overlapped, the Shannon index value
for open habitat is significantly different than the forest habitat (Figure
3a). This reflects open habitat has
higher scorpion diversity compared to the forest habitat, because open habitat
contains scattered boulders. Crevices
under boulders are a preferred habitat for scorpions to spend the day time.
The number of species reflects
the species richness. Species richness
is strongly dependent on sampling size and effort (Help et al. 1998). The species abundance is often a more
sensitive measure of a diversity parameter than species richness alone (Kempton 1979). To overcome this problem, the Margalef index was used.
Since, the 95% confidence intervals for the Margalef
index values in two habitats are not overlapped with each other, the Margalef index value for open habitat is significantly
different from forest habitat (Figure 3.c).
This index reflects two habitats have almost similar in species
richness. Species evenness is a measure
of how similar species are equally abundant (Lloyd & Ghelardi
1964; Magurran 2004). Evenness value range from
0.0-1.0. When the species are equally
abundant, evenness value is greater.
When the few species are dominant in the community, evenness is less (Magurran 2004).
Since the 95% confidence intervals for the Shannon evenness values of
two habitats are not overlapped, the Shannon evenness values are significantly
different in the forest and open habitats (Figure 3b). The higher Shannon evenness value of forest
habitat explains that scorpions found in forest habitat were more equally
abundant than the open habitat due to the high dominance of H. swammerdami in open habitats (Figure
2a). Similarly, forest habitat has
evenness value below 0.5, which is due to the high dominance of R. loebli in forest habitat (Figure 2b). Beta diversity of
habitats compares the species similarity between the two habitats (Magurran
2004). To
compare the similarity between two habitats, which was calculated as 0.5882 in Sørensen index in a way reflecting a more than 50% shared
species between two habitats. Similar
results were observed in previous studies as intra-specific and inter-specific
coexistence in several species of scorpions (Kaltsas
et al. 2009; Shehab et al. 2011; Lira et al. 2013). Thus, species might either co-occur in the
same habitat or co-occur in the same shelter (Warburg 2000).
Arboreal scorpion R. loebli prefers to occupy around heights of
121–180 cm range. This might be mainly
due to foraging opportunities and predator pressure. They are considered efficient predators of Isoptera, Hymenoptera, Diptera,
Hemiptera, while civets, mongoose, land monitors, and lizards are the predators
of them (personal observation).
Thus, R. loebli might prefer to forage
in this favourable height range without being consumed by another
predator. On the other hand, R. loebli prefers to inhabit around DBH of
361–480 cm range, which is above the average DBH level. The diameter of a tree considered as
contemplate of a niche area for an arboreal scorpion. Thus, they favour occupying a much larger
niche for obtaining more resources like prey, sites to rest and hide from
predators.
In conclusion, the five species
reported in the Archaeological site of Polonnaruwa
suggest high scorpion richness in this area.
This highlights the importance of conservation of historic ruins and
forest patches of the archaeological site to maintain scorpion fauna. Thus, the results presented here contribute
to the knowledge of the diversity of scorpions in these historically
significant sites that can serve as a basis for future research on the impact
of habitat modification and fragmentation on the population, distribution, and
ecology of scorpions.
Table 1.
Scorpion species found in Polonnaruwa Archaeological
Reserve, Sri Lanka in 2018.
|
Family |
Species |
|
Buthidae (28%) |
Charmus laneus |
|
|
Isometrus thwaitesi |
|
|
Reddyanus besucheti |
|
|
Reddyanus loebli |
|
Scorpionidae (72%) |
Heterometrus swammerdami |
Table 2.
Species diversity indices in Polonnaruwa
Archaeological Reserve, Sri Lanka.
|
Diversity index |
Open habitat |
Forest habitat |
|
No. of species (S) |
4 |
3 |
|
Total number of individuals recorded (N) |
327 |
52 |
|
Shannon Index (H’) |
0.6011 |
0.4869 |
|
Shannon Evenness (E) |
0.4336 |
0.4432 |
|
Margalef Diversity Index (DMg)
|
0.5181 |
0.5062 |
|
Sørensen index between open and forest habitat |
0.5882 |
|
For figures
& images - - click here
REFERENCES
Abeynayake, K., R.N. de Fonseka
& R. Sandhya (1993). A Survey of the vegetation of Damila Mahasaya in Polonnaruwa. Journal
of the Royal Asiatic Society of Sri Lanka 38: 127–140.
Ashton, M.S., S. Gunatilleke, N. de Zoysa, M.D. Dassanayake, N. Gunatilleke &
S. Wijesundera (1997). A Field Guide to the Common Trees
and Shrubs of Sri Lanka. Wildlife Heritage Trust Publications (Pvt.) Ltd, Colombo, 430pp.
Bahir, M.M., P.K.L. Ng, K.
Crandall & R. Pethiyagoda (2005). A conservation assessment of the
freshwater crabs of Sri Lanka. The Raffles Bulletin of Zoology 12:
121–126.
Bedjanič, M. (2004). Odonata fauna of Sri Lanka:
Research state and threat status. International Journal of Odonatology 7(2): 279–294. https://doi.org/10.1080/13887890.2004.9748216
Fernando, P., J. Jayewardene, T.
Prasad, W. Hendavitharana & J. Pastorini (2011). Current status of Asian
elephants in Sri Lanka. Gajah 35: 93–103. https://doi.org/10.18987/jjwrs.37.0_37
Help, C.H.R., P.M.J. Herman &
K. Soetaert (1998). Indices of diversity and
evenness. Oceanis 24: 61–87.
Kaltsas, D., I. Stathi
& M. Mylonas (2009). Intraspecific differentiation of
social behavior and shelter selection in Mesobuthus
gibbosus (Brullé, 1832)
(Scorpiones: Buthidae). Journal
of Ethology 27: 467–473. https://doi.org/10.1007/s10164-008-0144-6
Karunaratne, I.W.A.P. & J.P. Edirisinghe (2008). Keys for the identification of
common bees of Sri Lanka. Journal of the National Science Foundation of Sri
Lanka 36(1): 69–89. https://doi.org/10.4038/jnsfsr.v36i1.134
Kempton, R. (1979). The Structure of Species Abundance
and Measurement of Diversity. Biometrics 35: 307–321.
Kittle, A.M., A.C. Watson &
T.S.P. Fernando (2017). The ecology and behaviour of a protected area
Sri Lankan leopard (Panthera pardus kotiya) population. Tropical
Ecology 58(1): 71–86.
Kovařík, F., G. Lowe, K.B. Ranawana, D. Hoferek, V.A.S. Jayarathne, J. Plíšková & F. Šťáhlavský (2016). Scorpions of Sri Lanka (Scorpiones: Buthidae, Chaerilidae, Scorpionidae) with
description of four new species of the genera Charmus
Karsch, 1879 and Reddyanus Vachon,
1972, stat. n. Euscorpius 220: 1–133.
Kovařík, F., K.B. Ranawana,
V.A.S. Jayarathne, D. Hoferek
& f. Šťáhlavský (2019). Scorpions of Sri Lanka
(Arachnida: Scorpiones). Part III. Heterometrus yaleensis
sp. n. (Scorpionidae). Euscorpius
283: 1–13.
Kovařík, F., K.B. Ranawana,
V.A.S. Jayarathne, S. Karunarathna
& A. Ullrich (2018). Scorpions of Sri Lanka (Arachnida: Scorpiones).
Part II. family Hormuridae Euscorpius
258: 1-8. http://www.science.marshall.edu/fet/euscorpius/example.pdf
Kularatne, S.A.M., N.P. Dinamithra, S. Sivansuthan,
K.G.A.D. Weerakoon, B.Thillaimpalam,
V. Kalyanasundram & K.B. Ranawana
(2015). Clinico-epidemiology of stings and envenoming of Hottentotta tamulus
(Scorpiones: Buthidae), the
Indian red scorpion from Jaffna Peninsula in northern Sri Lanka. Toxicon 93: 85–89. https://doi.org/10.1016/j.toxicon.2014.11.225
Lira, A.F.A., A.M. Souza, A.A.C.
Silva Filho & C.M.R. Albuquerque (2013). Spatio-temporal microhabitat use by two
co-occurring species of scorpions in Atlantic rainforest in Brazil. Zoology
116: 182–185. https://doi.org/10.1016/j.zool.2013.01.002
Lloyd, M. & R.J. Ghelardi (1964). A table for calculating theequitability’component of species diversity. The
Journal of Animal Ecology 33: 217-225pp. https://doi.org/10.2307/2628
Lourenço, W.R. (2002). Further taxonomic
considerations about the genus Charmus Karsch, 1879 (Scorpiones, Buthidae), with the description of a new species from Sri
Lanka. Entomologische Mitteilungen aus dem Zoologischen Museum Hamburg 14(165):
17–25.
Magurran, A.E. (1988). Ecological Diversity and
its Measurement. Princeton University Press, London, 168pp.
Magurran, A.E. (2004). Measuring Biologica
Diversity. Blackwell Publishing, Victoria, 256pp.
Mayer, P. (2000). Hot Spot: Forest policy in
Europe: achievements of the MCPFE and challenges ahead. Forest Policy and
Economics 1: 177–185. https://doi.org/10.1016/s1389-9341(00)00018-6
Mittermeier, R.A., W.R. Turner,
F.W. Larsen, T.M. Brooks & C. Gascon (2011). Global Biodiversity
Conservation: The Critical Role of Hotspots, pp. 3–22. In: Zachos, F. & J. Habel
(eds.). Biodiversity Hotspots. Springer, Berlin, Heidelberg, 565pp. https://doi.org/10.1007/978-3-642-20992-5
Naggs, F., D. Raheem, K.B. Ranawana & Y. Mapatuna (2005). The darwin
initiative project on Sri Lankan land snails : patterns of diversity in Sri
Lankan forests. The Raffles Bulletin of Zoology 12: 23–29.
Newlands, G. (1972). Ecological adaptations of Kruger
National Park scorpionids (Arachnida: Scorpionides). Koedoe 15:
37–48. https://doi.org/10.4102/koedoe.v15i1.666
Nijman, V. (2012). Purple-faced langurs in
human-modified environments feeding on cultivated fruits: a comment to Dela (2007, 2012). International Journal of Primatology
33: 743–748. https://doi.org/10.1007/s10764-012-9609-0
Nime, M.F., F. Casanoves,
D.E. Vrech & C.I. Mattoni
(2013). Relationship
between environmental variables and surface activity of scorpions in the Arid
Chaco ecoregion of Argentina. Invertebrate Biology 132(2): 1–11. https://doi.org/10.1111/ivb.12019
Pande, S., D. Bastawade,
A. Padhye & A. Pawashe
(2012). Diversity
of scorpion fauna of Saswad-Jejuri, Pune District,
Maharashtra, western India. Journal of Threatened Taxa 4(2): 2381–2389. https://doi.org/10.11609/jott.o2910.2381-9
Pande, S., A. Pawashe,
D.B. Bastawade & P.P. Kulkarni (2004). Scorpions and molluscs: Some new dietary records for Spotted Owlet Athene
brama in India. Newsletter for Ornithologists
1(5): 68–70.
Prendini, L. (2005). Scorpion diversity and
distribution in southern Africa: Pattern and process, pp. 25–68. In: Huber,
B.A., B.J. Sinclair & K.-H. Lampe (eds.) African Biodiversity:
Molecules, Organisms, Ecosystems. Proceedings of the 5th
International Symposium on Tropical Biology, Museum Alexander Koenig, Bonn.
Springer, Verlag, New York, 68pp.
Polis, G.A. (1990). Life
history. The Biology of Scorpions. Stanford University Press,
Stanford, 293pp.
Ranawana, K.B., N.P. Dinamithra,
S. Sivansuthan, I.I. Nagasena,
F. Kovařík & S.A.M. Kularatne
(2013). First
report on Hottentotta tamulus
(Scorpiones: Buthidae) from
Sri Lanka, and its medical importance. Euscorpius
155: 1–10. https://doi.org/10.18590/euscorpius.2013.vol2013.iss155.1
Samarawckrama, V.A.M.P.K., M.D.B.G. Janananda, K.B. Ranawana & A.
Smith (2005). Study of the
distribution of the Genus Poecilotheria of the
Family Theraphosidae in Sri Lanka. Ceylone Journal of Science 34: 75–86.
Shehab, A.H., Z.S. Amr & J.A.
Lindsell (2011). Ecology and
biology of scorpions in Palmyra, Syria. Turkish Journal of Zoology
35(3): 333–341. https://doi.org/10.3906/zoo-0904-19
van der Poorten,
G.M. & N.E. van der Poorten (2016). The Butterfly Fauna of Sri
Lanka. Lepodon Books, Torronto,
418pp.
Warburg,
M.R. (2000). Intra- and
interspecific cohabitation of scorpions in the field and the effect of density,
food, and shelter on their interactions. Journal of Ethology 18: 59–63. https://doi.org/10.1007/s101640070026