1 Original Article
2 Study of Diversity and Morphometry in Edible Bivalves and Gastropods from a Coastal
3 Wetland in Sarawak
1* 3 1 1 4 Mohd Hanafi Idris , Hadi Hamli , Abu Hena Mustafa Kamal , Roslizawati Ab Lah , Nik
5 Mohd Shibli Nik Jaafar2
6
7 1Faculty of Fisheries and Food Science, Universiti Malaysia Terengganu, 21030 Kuala Nerus,
8 Terengganu, Malaysia
9 2Faculty of Science and Marine Environment, Universiti Malaysia Terengganu, 21030 Kuala
10 Nerus, Terengganu, Malaysia
11 3Department of Animal Science and Fishery, Faculty of Agriculture and Food Sciences
12 Universiti Putra Malaysia Bintulu Sarawak Campus
13 Nyabau Road, P.O. Box 396, 97008, Bintulu, Sarawak, Malaysia
14 *Corresponding author, Email address: [email protected]
15
16 Abstract
17 Diversity and morphometry of edible, bivalve and gastropod classes of mollusc were 18 investigated from July e82010 to January 2012, for a particular set of bivalve species, at 19 selected coastal divisions of Sarawak including Kuching, Sibu, Mukah, Bintulu, Miri, 20 Limbang, and Lawas. A total of 41 edible species were recorded and identified; comprising 21 11 families of gastropods represented by 21 species, and 12 family of bivalves represented by 22 20 species. For bivalves, species of the family Cyrenidae (Geloina erosa, G. expansa and G. 23 bengalensis) were more widely distributed than bivalve species. The gastropod, family of 24 Potamididae (Cerithidea obtusa, C. quadrata, C. rizophorarum and Telescopium 25 telescopium) were also commonly observed along the entire seven divisions. Species 26 diversity was found to be highest in Bintulu division for both classes, and consisted of 13 27 species of gastropod and 11 species of bivalve. Jaccard’s index showed high similarity 28 amongst edible bivalves for Limbang division versus Miri division (0.75), and for Limbang 29 versus Lawas (0.75). For gastropods, Sibu versus Mukah showed higher similarity (0.50). 30 Morphometric study of bivalves indicated that VPM/SL and LCT/SL features were 31 applicable as an identification key to differentiate between Geloina spp. This morphometric 32 identification key could be developed further for identification of other species in the mollusc 33 family.
34
35 Keywords: Edible gastropod, bivalve, diversity, distribution, Sarawak
36
37 1. Introduction
38 The State of Sarawak, Malaysia contains vast areas of wetlands, including brackish
39 water, coastal marine, and mangrove areas. The state wetlands comprise contains 1.24 million
40 hectares which covers 13% of the state’s total land area (Page, 2011). This wetland provides
41 support for extensive floral and faunal biodiversity. Molluscs are part of the faunal
42 composition of the wetlands of Sarawak, and one of the most important protein resources to
43 surrounding human the communities. Apart from providing good nutrition, molluscs play an
44 important economic role in Sarawak.
45 The contribution of edible mollusc to local economies within Sarawak is high,
46 notwithstanding, this resource has yet to be well documented. To the best of our knowledge,
47 only a few studies have documented species of bivalves and gastropods occurring in
48 Malaysia; (Hamli et al., 2015a; Hamli et al., 2015b; Idris et al., 2011; Abdullah, Sidi, & Aris,
49 2007; Sallih, 2005; Abu Hena et al., 2004; Nakao, Nomura & Satar, 1989). Previous study
50 has recorded edible mollusc distribution in the tropical region of Thailand (Nateewathana,
51 1995), but it is difficult to develop an accurate figure for local consumption of edible bivalve
52 and gastropod species in Sarawak, Malaysia. This paper aims to investigate the diversity, 53 morphological characteristics and habitat of edible mollusc to improve information for the
54 selected division in Sarawak. The majority of the bivalve and gastropod species found in
55 wetland coastal waters of Sarawak, in the coastal divisions, hence this regional study provides
56 valuable information on bivalves and gastropods, which could be used to further develop bivalve and
57 gastropod fisheries in future.
58
59 2. Materials and Methods
60 2.1 Study Area
61 Samples were collected from native markets, and fish markets from the selected seven
62 divisions of Kuching, Mukah, Sibu, Bintulu, Sibu, Bintulu, Miri, and Lawas, Sarawak.
63 (Figure 1). Samples were preserved in ice-filled boxes and transferred to the laboratory for
64 further analysis and study.
65 2.2 Species Identification and Morphometric Study as a Demarcation Tool
66 The identification of bivalves was conducted following procedures common to a
67 number of researchers, namely, Morton (1984), Poutiers (1998), Mass, O’ Mullan, Lutz, and
68 Vrijenhoek (1999), Yuh-Wen, Hon-Cheng, Sin-Che and Chaolun (2001), and Okutani
69 (2017). Gastropod samples were identified following the studies by Nateewathana (1995),
70 Kohler and Glaubrecht (2001), Poutiers (1998), Perez, Clark and Lydeard (2004), Tan and
71 Clements (2008), and Mujiano (2009). Specimens of bivalve and gastropod were measured
72 according to morphometric characteristics using digital Mitutyo vernier calliper (0.01±mm)
73 (Hamli et al., 2015a and Idris et al., 2008). A total of 20 characteristics (15 for bivalve and 5
74 for gastropods) were used to differentiate the species (Table 1; Figure 2).
75 The current morphometric focused only on a single genus of bivalve from Geloina
76 genus (G erosa, G. expansa, G. bengalensis.) with a total of 436 matured individuals. The 77 sum of 15 shell morphometrics, numbered one through fifteen (Table 1) had been measured,
78 which were then divided by shell length to convert the measurements to proportionate ratio
79 by size, for each Geloina species.
80 2.3. Statistical Analysis
81 Measurements of collected species from the selected Sarawak divisions were
82 correlated with geographical source to establish a distribution pattern. Similarities in species
83 numbers within the respective divisions were evaluated as either present (1), or absent (0)
84 based on Jaccard’s Index (Ludwig & Reynolds, 1988).
85 Jaccard’s Index = A/(A+B+C)
86 Where
87 A = total number of species present in both communities
88 B = the number of species present in community 1 but not at community 2
89 C = the number of species present in community 2 but not at community 1
90 The samples from the Geloina species, from the study areas in the present study were
91 chosen for morphometric differentiation within species by scrutinising shell proportion ratio
92 using analysis of variance (ANOVA) with general linear model (GLM), and using statistical
93 analysis computer software (SAS) version 9.1 (SAS Institute, 2004).
94
95 3. Results and Discussion
96 3.1 Distribution
97 A total of 41 edible species comprised 12 families of bivalves representing 20 species
98 (Table 2), and 11 families of gastropods representing 21 species (Table 3) were recorded, and 99 identified from seven divisions of Sarawak (Figures 3 and 4). Cyrenidae (Bivalve) and
100 Potamididae (Gastropod) families were widely distributed in seven and six divisions,
101 respectively. Bintulu division presented the greatest variety of bivalves and gastropods with a
102 total of 24 species (13 gastropods, and 11 bivalves) recorded, while Sibu division presented
103 only minor variation.
104 Mollusc species presented in this study were low when compared to Printrakoon,
105 Wells and Chitramvong (2008), and other studies, due to the current study focus on edible
106 species alone. Printrakoon et al. (2008), Frith, Tantanasiriwong and Bathia et al. (1976) and
107 Brandt (1974) recorded 47, 43 and 56 species of mangrove, coastal, and estuarine mollusc,
108 respectively in Thailand. Macintosh, Ashton and Havanon (2002) found 34 species of
109 mollusc in the Ranong biosphere reserve in Thailand. Jiang and Li (1995) recorded 52
110 species of in the Jiulong river estuary, China. However, the above studies were taxonomic,
111 diversity and distribution studies, rather than studies specific to edible molluscs in specified
112 coastal, tropical wetlands. The current study indicates that the diversity of edible mollusc in
113 this region is less, although Somchai (1995) reported that gastropods were a major class of
114 mollusc with high market value on Phuket Island, Thailand.
115 The marsh clams, Geloina erosa and G. bengalensis were both within the sampling
116 area. Within the Indo-Pacific area, they can be described under the subgenus Geloina
117 (Morton, 1984), which subgenus is also distributed in the mangrove area of China (Han et al.,
118 2003), Australia (Wells, 1986) and Thailand (Printrakoon et al., 2008). Species Geloina
119 expansa (Bivalvia), Cerithidea rizophorarum, and C. obtusa (Gastropoda) were found
120 distributed within four divisions in Sarawak. Other gastropod and bivalve species were found
121 within one to three divisions only. Presence of G. erosa and G. bengalensis at almost study
122 area was equivalent with to presence of mangrove area at Sarawak. 123
124 3.2 Similarity Indices
125 Analysis of the similarity index, described above, showed high similarities for
126 bivalves in Limbang versus Miri (0.75), and in Limbang versus Lawas (0.75), and high
127 lower similarity for edible gastropod in Sibu versus Mukah (0.50). Similarities as low as 0.00
128 was observed for bivalves in Kuching versus Mukah divisions and in Lawas versus Kuching.
129 Similarities were also as low as 0.00 for edible gastropod in Lawas versus Sibu, Lawas versus
130 Mukah, Lawas versus Bintulu, Lawas versus Miri, Lawas versus Limbang, Bintulu versus
131 Sibu and Bintulu versus Mukah divisions. The similarity index value for edible bivalve and
132 gastropod between each division could probably account for or be related to the psence of
133 wide mangroves and muddy area supporting suitable habitats these molluscs. Furthermore,
134 Puri, Namboothri and Shanker (2014) described that increasing similarity of gastropod
135 communities showed a relationship with decreasing geographical distance between study
136 locations.
137 3.3 Morphometrics
138 Study on 14 calculated ratios of morphometric characteristics on Geloina erosa, G.
139 expansa and G. bengalensis indicated significant difference (p<0.05) for VPM/SL and
140 LCT/SL (Table 4). Length of cardinal tooth proportion with SL was recorded as significantly
141 higher (p<0.05) for G. bengalensis when compared with other species. For G. erosa,
142 characteristics recorded no significant difference (p>0.05) when compared with G. expansa.
143 Geloina bengalensis recorded significant difference (p<0.05) for VPM/SL since this
144 characteristic is absent in G. erosa and G. expansa.
145 Previous study of different populations of Corbiculidae (Corbicula fluminea) showed
146 shell height to be significantly correlated with shell length (Araujo, Moreno, & Ramo, 1993). 147 Morton (1984) reported that width and height of G. erosa and G. expansa were extremely
148 variable which caused these characteristics to be unreliable for analysis of dimensional
149 relationships. There are many reasons that can cause such outcome. Some bivalves grow to
150 become higher and wider to overcome the turbulence and currents in the surrounding area
151 (Hinch & Bailey, 1988). With respect to the mangrove habitat of this species, they are always
152 affected by tide. Bivalve shell, especially from a mangrove area was vulnerable to the erosive
153 effects of the acid mangal soil (Morton, 1984). Moreover, the presence of predators can also
154 affect shell characteristics, as reported by Preston and Roberts (2006) on Calliostoma
155 zizyphinum. Therefore, the current study did not depend on major dimensions (length, height
156 and width) alone, but an additional characteristic was used to support differentiation between
157 species. The supplementary features chosen were significant in morphometric assessment for
158 gastropod and bivalve to reduce or remove attribution to impacts of the environment, or and
159 predators.
160 4. Conclusion
161 The higher number of edible bivalves and gastropods in Sarawak could be due either
162 to habitat preferences of molluscs, or to over exploitation of the natural resource by local
163 fishermen, e.g., due to rapid urbanization and, customer demand. This may affect the total
164 edible mollusc diversity within Sarawak. Diversity, abundance, and shell features of edible
165 molluscs are significantly affected by changes in habitat. Therefore, fluctuation in
166 environmental conditions, generates changes shell formation, which in turn influence species
167 identification, while the current study was able to identify new shell characteristics to support
168 discrimination between species exposed to abiotic variations. Further study is required to
169 identify, monitor and classify the diversity and population status of edible mollusc in this
170 region in support of conservation and management. 171
172 Acknowledgments
173 The research was supported by funding of project No. 5523703 FRGS, from the
174 Ministry of Education Malaysia. Technical and logistic support was provided by Universiti
175 Putra Malaysia Bintulu Sarawak Campus. The authors would like to thank Mr. Azwandi and
176 Awangku Nizam for their help during data collection in Sarawak, which made this study
177 possible.
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265 266
267
268
269 270 Figure 1 Sampling location from seven divisions of Sarawak.
271
272
273
274
275
276
277 278
279 Figure 2 Measurements of shell characters for bivalvia and gastropoda (adopted from 280 Mass et al., 1999; Ramesh and Ravichandaran, 2008). Note: 1(SL), 2(SH), 3(SW), 4(LL), 281 5(PL), 6(AL), 7(UL), 8(LCT), 9(LPAS), 10(PW), 11(PW), 12(PVM), 13(PAPM), 282 14(AAAM), 15(VPM) 16(sl), 17(sw), 18(al), 19(aw), 20(op).
283 284 285 Figure 3 Edible bivalve species recorded from Sarawak: (A) Geloina expansa, (B) 286 Geloina erosa, (C) Geloina bengalensis (D) Meretrix meretrix (E) Meretrix lyrata (F) 287 Paratapes undulatus (G) Circe scripta (H) Solen regularies (I) Solen lamacrkii (J) 288 Pharella acutidens.
289
290
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292 293
294
295 Figure 3 (Cont’d) (K) Amusium pleuronectes, (L) Tegillarca granosa, (M) Pholas 296 orientalis, (N) Gluconome virens, (O) Placuna placenta, (P) Crassostrea lugubris, 297 (Q) Isognomon ephippium, (R) Sinanodonta woodiana, (S) Pilsbryoconcha exilis 298 (T) Arcuatula arcuatula.
299 300 301
302 Figure 4 Edible gastropods from Sarawak; (A) Cerithidea obtusa, (B) Cerithidea 303 rizophorarum, (C) Trochus radiatus, (D) Cerithidea quoyii, (E) Telescopium 304 telescopium, (F) Monodonta labio, (G) Nerita articulata, (H) Nerita chamaeleon, 305 (I) Melo melo, (J) Nerita albicilla, (K) Clithon ritropictus, (L) Planaxis sulcatus.
306
307 308 309
310 Figure 4 (continued) (M) Brotia costula, (N) Melanoides costellaris, (O) Tylothais virgata 311 (P) Blanocochlis glandiformis, (Q), Tylomelania helmuti (R),Turbo crasus, (S) Pilla 312 ampullacea, (T), Ellobium aurisjudae and (U) Pomacea bridgesii.
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315
316
317
318 319 Tables
320 321 Table 1 Morphometric characteristic used for bivalve identification with the abbreviation 322 (*=Additional characteristic used during study period) 323 Measurement Abbreviation Details Number
1 SL Distance from the anterior margin to posterior margin
2 SH Distance between ventral margin and umbo
3 SW Distance from left shell to the right shell
4 LL Ligament length
5 UL Distance from umbo to posterior margin
6 AL Distance from the posterior part of umbo to the anterior margin of the shell
7 PL Distance from the posterior part of umbo to the posterior margin of the shell
8 LCT Length from anterior cardinal tooth to posterior cardinal tooth
9 LPAS Distance from anterior adductor muscle scar to posterior adductor muscle scar
10 PW Wide of posterior adductor muscle scar
11 AW Wide of anterior adductor muscle scar
12 PVM Distance from ventral margin to pallial line
13 PAPM Distance from posterior adductor muscle scar to posterior margin of the shell
14 AAAM Distance from anterior adductor muscle scar to anterior margin of the shell
15 VPM Ventral posterior margin length
16 sl Shell length
17 sw Shell width
18 al Aperture length
19 aw Aperture width
20 op Outer lip thickness
324 325 Table 2 Checklist and distribution of edible bivalve species from eight different divisions in Sarawak, Malaysia.
Family Species Habitat Kuching Sibu Mukah Bintulu Miri Limbang Lawas
Veneridae Circe scripta Salt water - - - + - - -
Paratapes undulatus Salt water - - + - - - -
Meretrix meretrix Salt water - - - + - - -
Meretrix lyrata Salt water + ------
Solenidae Solen regularies Salt water + ------
Solen lamarckii Salt water + ------
Brackish Pharella acutidens + ------water
Brackish Cyrenidae Geloina bengalensis + + - + + + - water
Brackish Geloina erosa - + + + + + + water
Brackish Geloina expansa - - - + + + + water
Unionidae Sinanodonta woodiana Fresh water - - - + + - -
Pilsbryoconcha exilis Fresh water - - - - + - -
Arcidae Tegillarca granosa Salt water + - - + - - -
Myoida Pholas orientalis Salt water + ------
Gluconomidae Gluconome virens Salt water + ------
Pectinidae Amusium pleuronectes Salt water + - - + - - -
Placunidae Placuna plcenta Salt water - - - + - - -
Ostreidae Crassostrea lugubris Salt water - - - + - - -
Mytilidae Arcuatula arcuatula Salt water ------+
Isognomonidae Isognomon ephippium Salt water - - - + - - -
326 Note: (+) = Present, (-) = Absent
327
328
329
330
331
332
333
334
335
336 337 338 Table 3 Checklist of gastropod species existing from eight different divisions in Sarawak
Family Species Kuching Sibu Mukah Bintulu Miri Limbang Lawas
Neritidae Nerita chamaeleon Salt water - - - + - - -
Nerita articulata Brackish water + - + - - - -
Nerita albicilla Salt water - - - + - - -
Clithon retropictum Brackish water - + - - - - -
Cerithidea Brackish water Potamididae rizophorarum + + + - - + -
Cerithidea obtusa Brackish water + + + - + - -
Cerithidea quoyii Brackish water ------+
Telescopium Brackish water telescopium ------+
Ampullariidae Pomacea bridgesii Fresh water - - - + - - -
Pilla ampullacea Fresh water + - - + + + -
Trochidae Trochus radiatus Salt water - - - + - - -
Monodonta labio Salt water - - - + - - -
Pachychilidae Brotia costula Fresh water - - - + - - -
Tylomelania helmuti Fresh water - - - + + - -
Thiaridae Melanoides costellaris Fresh water + ------
Blanocochlis Fresh water glandiformis - - - + - + -
Planaxide Planaxis sulcatus Salt water - - - + - - -
Turbinidae Turbo crasus Salt water - - - + - - -
Muricidae Tylothais virgata Salt water - - - + - - -
Volutidae Melo melo Salt water - - - + - - -
Melampidae Ellobium aurisjudae Brackish water + ------
339 Note : (+) = present; (–) = absent
340
341
342
343
344
345
346
347 348
349
350
351 Table 4 Analysis of one way ANOVA with general linear model (GLM) for 14 352 morphometric characteristic proportion with shell length of three Geloina 353 species
Morphometric Geloina erosa Geloina expansa Geloina F value p characteristic bengalensis N=194 N=139 N=103
SH/SL 0.89±0.21a 0.89±0.01a 0.93±0.01a 0.39 0.678ns
SW/SL 0.53±0.03a 0.54±0.01a 0.55±0.01a 0.11 0.895ns
UL/SL 0.75±0.04a 0.78±0.01a 0.80±0.00a 0.58 0.564ns
LL/SL 0.32±0.02a 0.31±0.00a 0.34±0.01a 0.91 0.409ns
AL/SL 0.56±0.03a 0.58±0.01a 0.60±0.01a 0.66 0.523ns
PL/SL 0.72±0.04a 0.75±0.01a 0.60±0.01a 0.48 0.625ns
PAPM/SL 0.05±0.00a 0.05±0.00a 0.05±0.00a 1.99 0.149ns
AAAM/SL 0.05±0.00a 0.05±0.00a 0.05±0.00a 1.22 0.305ns
PVM/SL 0.10±0.01a 0.10±0.00a 0.09±0.00a 1.39 0.261ns
LPAS/SL 0.60±0.03a 0.63±0.00a 0.63±0.00a 0.68 0.535ns
AW/SL 0.12±0.01a 0.12±0.00a 0.13±0.00a 1.78 0.180ns
PW/SL 0.17±0.01a 0.15±0.00a 0.17±0.00a 1.91 0.160ns
LCT/SL 0.16±0.01ab 0.14±0.00a 0.17±0.00b 4.45 0.017
VPM/SL NA NA 0.36±0.00 NA NA
354 SL=Shell length, SH=Shell height , SW=Shell weight, UL=Umbo length, LL=Ligament 355 length, AL=Anterior length, PL=Posterior length, PAPM=Posterior adductor scar to posterior 356 margin, AAAM=Anterior adductor scar to anterior margin, PVM=Pallial line to ventral 357 margin,LPAS=Length of posterior adductor scar to anterior adductor scar, AW=Anterior 358 adductor scar width, PW=Posterior adductor scar width, LCT=Length of cardinal tooth, 359 VPM=Ventral posterior margin length, NA=Not available.
360
361 Note: difference superscripts indicate a significantly difference at level p<0.05 using Tukey 362 mean comparison, ns: no significantly difference
363
364
365 366
367
368
369