Morphological Variation of Asian Small Lizards Genus Tytthoscincus in Indonesia (Firmansyah, et a.
Morphological Variation of Asian Small Lizards genus Tytthoscincus Linkem.
Diesmos & Brown (Squamata : Scincida.
in Indonesia Richo Firmansyah1*.
Awal Riyanto2.
Nia Kurniawan1 1Department of Biology.
Faculty of Mathematics and Natural Sciences.
University of Brawijaya.
Malang.
Indonesia 2Museum Zoologicum Bogoriense.
Research Center of Biology.
National Research and Innovation Agency (BRIN).
Bogor.
Indonesia Abstract Morphological variations in species with a relatively broad distribution, including the genus Tytthosincus, were likely a result of island isolation.
This research was conducted to map the morphological variations of the genus Tytthoscincus in Indonesia.
A total of 32 specimens of the Tytthoscincus scientific collection in the Zoologicum Bogoriense Museum (MZB) - National Research and Innovation Agency (BRIN) and identified as T.
textus, and T.
parvus have been examined and data collection which includes six morphometric characters and 12 meristic characters.
Morphometric data were analyzed in univariate and multivariate.
Univariate analysis was carried out by the Kruskal-Wallis test, while multivariate analysis was done with the Principal Component Analysis (PCA) test.
The results showed morphology in T.
temmincki and T.
textus, namely the number of loreal scales and tympanum diameter.
Both T.
temmincki and T.
textus consist of two groups, but the morphological variation in T.
temmincki and T.
textus in this study has yet to provide certainty as a different species.
However, one was T.
Type 2, isolated from other species on Jampea Island.
Sulawesi.
Further research was needed to clarify the taxonomic status of these variations by increasing the number of adequate samples supported by the molecular analysis approach.
Keywords: meristic, morphometric, species.
Tytthoscincus, variation.
INTRODUCTIONA
In 2011.
Linkem et al.
Classified Sphenomorphus species into a new genus.
Tytthoscincus.
Genetic and morphological data show that small mountain species such as S.
butleri (Boulenge.
Ishaki (Grisme.
, and others form a monophyletic group centered phylogenetically on the genus Tytthoscincus .
The morphological characteristics of the genus Tytthoscincus are a body size of less than 45 mm (SVL= Snout Vent Lengt.
, and temporal scales cannot be distinguished from lateral body scales in either size or shape .
Tytthoscincus weighs around 0.
63 Ae 3.
25 grams.
The genus Tytthoscincus is distributed in the Southeast Asian region such as Malaysia.
Indonesia, to the Philippines .
Lygosoma temmincki was described by Dumyril and Bibron in 1839, with morphological characteristics of this species having jaws parallel to the snout, smooth scales, small longitudinal slit-shaped ear holes, and short limbs.
Lygosoma temmincki was found on Java Island .
Mueller, in 1894 described a species found on the island of Sulawesi at an altitude of 3900 meters above sea level as Lygosoma texum.
This species has morphological characteristics such as a short *Correspondence address:
Richo Firmansyah Email : richo.
firmansyah25@gmail.
Address : Dept.
Biology.
University of Brawijaya.
Veteran Malang 65145.
Indonesia.
Exp.
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13 No.
2, 2023
and pointed snout, no supranasal, and five supraocular scales.
The ventral part of the chin is gray.
The head length of L.
texum is around 50 mm, with a tail of 56 mm .
In 1897.
Lygosoma parvum was described by Boulenger with the morphological characteristics of an elongated body shape with a total body length of 78 mm, a short and blunt snout, scaly lower eyelids, four supraocular scales, eight supraciliary scales, no supranasal, unclear tympanum hole, hind limbs longer than forelimbs, and a brown body with dorsal yellowish brown dots.
Lygosoma parvum was found in Luhu.
Central Sulawesi, at 1000 - 1600 feet .
Linkem et al.
redescribed T.
Parvus characterized by a small body size of less than 45 mm, small fingers, and a fourth finger longer than or equal to the third finger.
This species is found on the island of Sulawesi .
Meanwhile.
Grismer et al.
described T.
Temmincki with morphological characteristics having a range of 4 - 5 supralabial scales, two loreal scales, 68Ae80 paravertebral scales, 62Ae72 ventral scales, 9Ae11 scales on the lamella of the fourth toe, smooth lamella texture, and a dark line on the dorsolateral .
The distribution of T.
temmincki is in Java.
Sumatra, and Sulawesi .
Grismer et al.
in 2016 described T.
textus with a short snout, 42 mm SVL size, reddish brown above with reticulation, and dark limbs .
Karin et al.
in 2016 also hypothesized that S.
textus belongs to the Tytthoscincus group.
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Morphological Variation of Asian Small Lizards genus Tytthoscincus in Indonesia (Firmansyah, et a.
characterized by an adult body size of 38 mm and a bright stripe on the postorbital and dorsolateral .
This hypothesis was proven by Grismer et al.
in 2017 by confirming that S.
textus is included in the phylogeny of the genus Tytthoscincus .
This study aimed to map the morphological variation of the genus Tytthoscincus in Indonesia.
MATERIAL AND METHOD
Data Collection The research data were taken from scientific collections in the form of wetpreserved specimens at the Museum Zoologicum Bogoriense (MZB).
Herpetology Laboratory.
Center for Biosystematics and Evolution Research.
Indonesian National Research and Innovation Agency (BRIN).
Cibinong.
Morphometric and meristic character data were collected to compare the genus Tytthoscincus in Indonesia (Fig.
Morphometric characters refer to Grismer et al.
, and specimens were measured using Image J software .
These morphometric characters include snout-cloaca distance length (SVL = snout-vent lengt.
measured from the rostral end to the cloaca margin, head length (HdL) measured from the anterior edge of the ear hole to the rostral end, tympanum diameter (TD, tympanum dept.
measured from the anterior to the posterior edge of the tympanum, length of the distance between the armpit and the thigh fold (AXG, axilla groin lengt.
, forelimb length (FL, forelimb limb.
, and hind limb length (HL, hind limb.
Meristic characters include the number of supralabials, attached to frontal scales, loreals (Fig.
middle, paravertebral, ventral scale rows, third finger lamellae, fourth finger lamellae, and meristic character with the shape of the Figure 1.
Distribution of variation Tytthoscincus.
Figure 2.
Morphological variation of Tytthoscincus based on the loreal scale number and tympanum diameter.
A = F.
temmincki type 1.
B = G.
temmincki type 2.
C = H.
textus type 1.
D=I.
textus type 2.
E = J.
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Morphological Variation of Asian Small Lizards Genus Tytthoscincus in Indonesia (Firmansyah, et a.
Data Analysis A total of 32 adult Tytthoscincus specimens .
rom Java and Sulawesi Islan.
were used in the analysis, and due to the small sample size, the statistical analysis did not differentiate between males and females.
These specimens were initially grouped into four operational taxonomic units (OTU/Operational Taxonomy Unit.
based on variations of loreal scales number and shape.
Morphometric data were standardized in ratios (HdL/SVL.
TD/SVL.
AXG/SVL.
FL/SVL.
HL/SVL, and TD/HdL).
Kruskal-Wallis analysis was carried out separately for each morphometric character to determine whether there were differences between OTUs (T.
temmincki type 1.
temmincki type 2.
textus type 2 and T.
This analysis method followed the Zar method .
Each morphometric character is a dependent variable, and OTU is an independent variable or Multivariate analysis used the principal component analysis (PCA) test to reduce multidimensional correlations into several uncorrelated variables.
All analyzes were performed by RStudio statistical software.
RESULT AND DISCUSSION
Tytthoscincus temmincki is grouped into two, namely, type 1 with the characteristic of only having one loreal scale and type 2 for specimens with two loreal scales.
The same applies to T.
textus in type 1 and type 2.
Meanwhile.
parvus is only one group because there is no variation in the number of loreal scales (Fig.
The results of the Kruskal-Wallis analysis showed that only two ratio characters had significantly different values between OTUs, consist of TD/SVL and TD/HdL (Table .
Of all OTUs.
parvus had the smallest tympanum size (TD/SVL and TD/HdL).
The largest tympanum belonged to T.
textus, with T.
textus type 1 and T.
textus type 2.
Multivariant analysis with PCA on PC1 and PC2 showed that only T.
parvus separated from temmincki type 1 and type 2, and T.
type 1 and type 2.
PC1 and PC2 cumulatively 8% of the variation (Table 2.
Fig.
In PC1, the morphometric ratio AXG/SVL had negative loading, while the other five morphometric ratios TD/SVL.
TD/HdL.
FL/SVL.
HL/SVL, and HdL/SVL had positive loading As for PC2.
AXG/SVL.
TD/HdL.
FL/SVL, and TD/SVL had positive loading values, while HL/SVL and HdL/SVL had negative loading Exp.
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Based on this study.
parvus is distinct from T.
temmincki and T.
The variation in the number of loreal scales in both T.
temmincki and T.
textus should be suspected as a phenomenon of intra-species variation.
This variation may be part of the ongoing speciation Another possibility is that the number of samples for morphometric analysis in both T.
temmincki type 1 and type 2 and T.
textus type 2 needed to be more significant .
ore samples The wide distribution area likely influences morphological variation in T.
temmincki and T.
The distribution area includes not only one large island but also small islands with complex structures .
Geographical barriers play a role in causing variation.
The range limit of a species is usually aligned with a significant barrier to dispersal, such as a river, sea, or mountain .
Figure 3.
Biplot principal component analysis of Tytthoscincus morphological variations on PC1 and PC2 In this study, the distribution of T.
type 2 was isolated from the distribution of other species on Jampea Island (Fig.
This allows the variation to be very different from T.
textus type 1, which originates from Sulawesi Island.
The morphological variations found can be used as a future taxonomic review and to provide certainty whether T.
textus type 2 from Jampea Island is different from T.
textus type 1 from Sulawesi Island as a distinct species, through molecular analysis and larger/ representative sample size.
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Morphological Variation of Asian Small Lizards genus Tytthoscincus in Indonesia (Firmansyah, et a.
Table 1.
Mean values and Kruskal-Wallis test statistics on variation in morphometric ratios between OTUs and comparison of meristic characters.
OTU
Character HdL/SVL SVL
AXG/SVL
FL/SVL
HL/SVL
TD/HdL Supralabials Infralabials Supraoculars Loreals Distribution type 1 .
203 A 0.
033 A 0.
545 A 0.
185 A 0.
283 A 0.
164 A 0.
, 6.
West Java.
East Java type 2 .
221 A 0.
033 A 0.
479 A 0.
175 A 0.
229 A 0.
148 A 0.
West Java type 1.
200 A 0.
034 A 0.
562 A 0.
159 A 0.
251 A 0.
170 A 0.
, 1.
Gorontalo.
Southeast Sulawesi.
Central Sulawesi textus type2 type 2 .
206 A 0.
040 A 0.
536 A 0.
173 A 0.
272 A 0.
196 A 0.
, 5.
South Sulawesi .
205 A 0.
024 A 0.
546 A 0.
158 A 0.
257 A 0.
116 A 0.
, 6.
Sulawesi.
Gorontalo.
Central Sulawesi P-value 456e-05* 368e-05* Notes: * significant.
HdL = head length.
SVL = snout-vent length.
AXG = axilla groin length.
FL = forelimb length.
HL = hind limb length, and TD = tympanum diameter.
Table 2.
Principle component analysis (PCA) and factor loading.
PCA variable PC1 Proportion of variance 0.
Cumulative Loading HdL/SVL TD/SVL AXG/SVL FL/SVL HL/SVL TD/HdL PC2
PC3
PC4
PC5
PC6
- 0.
- 0.
- 0.
- 0.
- 0.
- 0.
- 0.
- 0.
- 0.
- 0.
- 0.
- 0.
Notes: HdL = head length.
SVL = snout-vent length.
AXG = axilla groin length.
FL = forelimb length.
HL = hind limb length, and TD = tympanum diameter.
The existence of habitat isolation was formed due to evolutionary factors, consisting of population differentiation between isolated islands during the Pleistocene era, which resulted in fluctuating sea levels and the separation of land by shallow seas .
Spatial and temporal variation in intraspecific body size or morphology is driven by differences in the heritability of phenotypic traits and the basis of evolution and adaptation to environmental changes .
CONCLUSION
Morphological variations in T.
and T.
textus are based on the number of loreal scales and the diameter of the tympanum.
for T.
parvus, no such variation was found.
Both temmincki and T.
textus consist of two The morphological variations in this study in T.
temmincki and T.
textus do not provide certainty as different species.
However, one of them.
textus type 2, is isolated from Exp.
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Vol.
13 No.
2, 2023
other species on the Island of Jampea.
Sulawesi.
Further research is needed to clarify the taxonomic status of these variations by adding an adequate number of samples supported by molecular analysis approaches.
Acknowledgement This research was supported by the Research Assistant Program from the National Research and Innovation Agency (BRIN) (Number 4/II/HK/2.
We thank Wahyu Trilaksono, who has helped access the samples in this research.
REFERENCES