Sacura boulengeri (Heemstra, 1973) is a rare serranid fish (Subfamily: Anthiinae) having very distinct

distribution in the western Indian Ocean. The rarity of the species is evident from earlier reports and, so far, no related

studies on the species have been published except on taxonomy and distributional records. In the present investigation,

the length-weight relationship of Sacura boulengeri was estimated to be W = 0.0777 × L2.690 (with 95% confidence

intervals for b and r2). An analysis of the stomach contents revealed that sergestid shrimps and copepods were the major

food items of the diet

Akhilesh, K V

Bineesh, K K

Pillai, N G K

Sebastine, Manju

CMFRI Digital Repository

K. BINEESH, S. MANJU, K. AKHILESH, G. PILLAI267 Turk J Zool2012; 36(2): 267-270© TÜBİTAKdoi:10.3906/zoo-0907-91A preliminary study on the length-weight relationship of Sacura boulengeri (Heemstra, 1973) from Indian watersKinattumkara BINEESH*, Sebastine MANJU, Kallivalappil AKHILESH, Gopalakrishna PILLAICentral Marine Fisheries Research Institute, P. B. No. 1603, Ernakulam North P. O., Cochi - 682 018, Kerala - INDIAReceived: 30.07.2009Abstract: Sacura boulengeri (Heemstra, 1973) is a rare serranid fi sh (Subfamily: Anthiinae) having very disjunct distribution in the western Indian Ocean. Th e rarity of the species is evident from earlier reports and, so far, no related studies on the species have been published except on taxonomy and distributional records. In the present investigation, the length-weight relationship of Sacura boulengeri was estimated to be W = 0.0777 × L2.690 (with 95% confi dence intervals for b and r2). An analysis of the stomach contents revealed that sergestid shrimps and copepods were the major food items of the diet. Key words: Length-weight relationship, Anthiinae, Sacura boulengeri, Indian watersShort Communication* E-mail: bineeshmarine@yahoo.comTh e subfamily Anthiinae of the family Serranidae (Perciformes) consists of about 21 genera with 170 species (Nelson, 2006). Anthiine fi shes are beautifully colored fi shes that inhabit coral and deep-reef habitats in tropical and warm temperate seas, and some of these species are taxonomically confusing. Many anthiine fi shes are very few in collection because of their rarity. Th e genus Sacura is comprised of 4 species: Sacura boulengeri, S. speciosa, S. parva, and S. margaritacea (Heemstra and Randall, 1979). Th omas et al. (2008) reported S. boulengeri for the fi rst time from Indian waters based on 2 specimens. Until 2008, fewer than 10 specimens had been collected and reported worldwide. During 2008 and early 2009, an occasional landing of S. boulengeri was observed in the trawler bycatch landings along the Keralan coast (CMFRI, 2008). Knowledge of length-weight relationships (LWRs) is useful in fi shery science for assessing length-based growth and the well-being of the population. In the present work, the LWR (W = a × Lb) calculated for S. boulengeri specimens caught off  the western coast of India forms the fi rst reference for the species worldwide. A total of 74 specimens (65 males and 9 unsexed) with standard lengths (SL) ranging from 13 to 17.8 cm were collected in stray numbers from the miscellaneous bycatch of trawler landings at Cochin Fisheries Harbor (09°56ʹN, 76°16ʹE) on the southwestern coast of India during the period of May 2008-March 2009. Th e LWR was calculated using least squares regression on log transformation of the following equation:A preliminary study on the length-weight relationship of Sacura boulengeri (Heemstra, 1973) from Indian waters268W = a × Lb,where W = weight (g), L = length (SL, in cm), a = intercept (constant), and b = slope (regression coeffi  cient) of the regression line; the values of a and b were estimated. A slope (b) value less than 3 indicates that the fi sh becomes more slender as it increases in length, and a slope value greater than 3 denotes stoutness, indicating positive allometric growth. Deviation from the cube law is observed in most species as they change their body shape during growth. Th e morphometric measurements of the specimens were taken with a Mitutoyo digital vernier caliper with an accuracy of 0.5 mm based on the method of Randall and Heemstra (2006). Morphometric characteristics were then compared with earlier reports.  Th e distribution of S. boulengeri is strictly confi ned to the Arabian Sea, and it has been previously recorded only off  the coasts of Muscat, Oman (Heemstra and Randall, 1979; Randall, 1995); Sindh, Pakistan (Moazzam and Osmany, 2004); and western India (Th omas et al., 2008). It later occurred in the landings along the southwestern coast of India as an occasional bycatch (CMFRI, 2008). Sacura boulengeri is identifi ed based on the following characters: Dorsal fi n rays X, 14; gill-rakers (14-16) + (30-33); lateral-line scales 30-33; head large; third anal fi n ray prolonged; no scales on lower jaw. It is a beautiful fi sh with a brownish-green body featuring an olive-green shade and 4 prominent, irregular lavender-pink stripes. Th e head and preoperculum also have several lavender blotches, with the orbit encircled with lavender. In 1 of the specimens collected (175 mm in SL), a strikingly interesting feature was observed that has not been reported elsewhere and was not seen in any of the other specimens collected during the same time and from the same place. In earlier descriptions, only the third dorsal spine was elongated with a black pennant tip, but in this single specimen, both the second and third dorsal spines were found to be elongated with a black tip. Th e length of the second dorsal spine was recorded at 17.1% of the SL (compared to 7.5%-11% of the SL in earlier reports) and the third dorsal spine was 45.1% of the SL (Figure 1, Table).Length-weight relationship A total of 74 fi sh were analyzed for LWRs. Th e length range of the SL of the fi sh varied from 13 to 17.8 cm. Th e LWR for S. boulengeri was estimated as:W = 0.0777 × L2.690      (r2= 0.840).Th e 95% confi dence interval for the b value was between 2.41 and 2.96, indicating that S. boulengeri from Indian waters shows negative allometric growth. Suzuki et al. (1974) estimated the LWR, using fork length, for S. margaritacea from Japan, a species closely related to S. boulengeri, as: W = 0.173 × 10–4 L3.086 (n = 373). Th e logarithmic equation for the relationship between standard length (L) and total weight (W) for S. boulengeri is:Log W = –2.5554 + 2.6899 log L. Th e calculated curve for the LWR is presented in Figure 2. From the nature of the graph, it appears that there exists a linear relationship between standard length and weight. Th ere can be variations in LWRs as a result of diff erent factors, including geography, habitat, season, stomach condition, maturity, sex, and age (Tesch, 1971).Food and feeding Studies on the diet and feeding habits of these fi sh were carried out in order to better understand the trophic relationship in the marine ecosystem. Most of the specimens collected had empty stomachs. Some of the fi sh, however, fed heavily on sergestid shrimp and Acetes sp.; in one fi sh, Acetes sp. was 5 cmFigure 1. Sacura boulengeri (Heemstra, 1973), male.K. BINEESH, S. MANJU, K. AKHILESH, G. PILLAI269Table. Th e comparative morphometric data of S. boulengeri (SL = standard length, HL = head length). LocationMuscat1 Sindh1 Neendakara2 Manglore2 Cochin31979 2004 2005 2006 2008Sex Male Male Female Male MaleNo. examined 3 1 1 1 1Standard length (mm) 101-139 170 103.82 134.74 175Greatest body depth (% SL) 41-43 41.7 39.1 41.8 39.4Head length (% SL) 42-43 39.2 38.1 44 38.8Pectoral fi n length (% SL) 29-32 29.2 29.7 29.2 29.1Pelvic fi n length (% SL) 25-29 28.3 30.2 29.2 27.6Caudal peduncle length (% SL) 20-22 20.8 21 20.3 18.8Caudal peduncle depth (% SL) 12-14 12.5 14.6 12.3 13.1First dorsal spine length (% SL) 6.4-7.3 5.8 6.5 6 6.3Second dorsal spine length (% SL) 9.7-11 7.5 9.2 9.9 17.1*Th ird dorsal spine length (% SL) 52-66 55 40.9 50.8 45.1Fourth dorsal spine length (% SL) 13-15 14.2 13 13.6 13.1Th ird dorsal soft  ray length (%SL) 50-52 47.5 48.4 50.8 39Anal fi n length (% SL) 33-36 32.5 31 31.8 32First anal spine length (% SL) 7.6-8 7.5 7 7.3 6.6Second anal spine length (% SL) 14-17 15 12.6 14.6 12.6Second anal soft  ray length (% SL) 26-29 25 27.9 27.8 26.3Pelvic fi n spine length (% SL) 15-18 15 14 15.2 14.3Snout length (% HL) 20-21 21.3 21 20.4 19.1Orbit length (% HL) 26-28 27.7 27.5 27.6 23.5Interorbital width (% HL) 20-22 23.4 22 22 23.5Postorbital distance (% HL) 53-56 53.5 53 57.2 55.9Upper jaw length (% HL) 43-44 42.6 42 42.3 42.6Gill rakers (upper) 14-16 N.S.* 12 12 14Gill rakers (lower) 30-33 N.S.* 27 27 29-30Sources: 1Moazzam and Osmany, 2004; 2Th omas et al., 2008; and 3Cochin: present study. A preliminary study on the length-weight relationship of Sacura boulengeri (Heemstra, 1973) from Indian waters270found along with a few copepods. Suzuki et al. (1974) reported that S. margaritacea feeds on plankton and, primarily, on calanoid copepods. Sacura boulengeri was found mostly in demersal trawl bycatch landings along with species such as Priacanthus hamrur, Chelidoperca investigatoris, Pristigenys niphonia, Odontanthias rhodopeplus, Aphareus rutilans, Epinephelus diacanthus, Liopropoma cf. lunulatum, Nemipterus spp., Pseudanthias sp., Scolopsis sp., Sargocentron spp., and Cookeoulus spp., but it most commonly occurred along with O. rhodopeplus and P. hamrur. Th e occurrence of S. boulengeri in demersal trawl catches indicates a greater range of depth of occurrence (up to 200 m) than the range of 49-90 m that was reported previously (Heemstra and Randall, 1979; Moazzam and Osmany, 2004; Th omas et al., 2008).Th e wide range of areas requiring more in-depth exploration underscores the importance of this fi sh and creates opportunities for researchers to provide or expand the knowledge of a population or community of the species (Lopez et al., 2009). Although a large area of the Indian Exclusive Economic Zone (EEZ) remains unexplored, the expansion of fi shing to new waters and depths is bringing several new fi shes to commercial landings. Th is, in turn, may enable researchers to gain a better understanding of various aspects of the demersal ecosystem of the Indian EEZ.AcknowledgementsTh e authors are deeply grateful for the encouragement given by the Director of the CMFRI. We also express our sincere gratitude to Dr. Philip C. Heemstra, SAIAB, South Africa, and Dr. John E. Randall, Bishop Museum, USA, for providing the literature required for the preparation of this paper. Th e fi nancial assistance received from the CMLRE/MoES, Government of India, is thankfully acknowledged.10 10.5 11 11.5 12 12.5 13 13.5 14 14.5 15 15.5 16 16.5Length (cm)a = 0.077659b = 2.68997Weight (g)160140120200100806040Figure 2. Th e length-weight relationship of Sacura boulengeri from Indian waters. ReferencesCMFRI. 2008. New records from Indian waters. Cadalmin CMFRI Newsletter 119: 1- 32. Heemstra, P.C. 1973. Anthias conspicuus sp. nova (Perciformes: Serranidae) from the Indian Ocean, with comments on related species. Copeia 1973(2): 200-210. Heemstra, P.C. and Randall, J.E. 1979. A revision of the anthiine fi sh genus Sacura (Perciformes: Serranidae) with descriptions of two new species. J.L.B. Smith Inst. Ichthyol. Spec. Publ. 20: 1-13.Lopez, M.J., Cervantes, M.A., Herrera, V.E. and Rodríguez, R.J. 2009. Peces en las profundidades marinas. Revista Ciencia y Desarrollo 35(230): 20-25.Moazzam, M. and Osmany, H. B. 2004. A note on the occurrence of Sacura boulengeri (Pisces: Serranidae) along Pakistan Coast. Rec. Zool. Surv. Pakistan 15: 49-51.Nelson, J.S. 2006. Fishes of the World, 4th ed. John Wiley & Sons, Inc., New York. Randall, J.E. 1995. Coastal Fishes of Oman. Crowford House Publishing, Bathurst, Australia.Randall, J.E. and Heemstra, P.C. 2006. Review of the Indo-Pacifi c fi shes of the genus Odontanthias (Serranidae: Anthiinae) with descriptions of two new species and a related new genus. Indo-Pacifi c Fishes 38: 32.Suzuki, K., Kobayashi, K., Hioki, S. and Sakamoto, T. 1974. Ecological studies of the anthiine fi sh Sacura margaritacea in Suruga Bay, Japan. Jap. J. Ichthy. 21(1): 21-33.Tesch, F.W. 1971. Age and growth. In: Methods for Assessment of Fish Production in Freshwaters (ed. W.E. Ricker). Blackwell Scientifi c Publications, Oxford, pp. 99-130.Th omas, S., Sreeram, M.P., George, R.M., Naomi, T.S. and Sanil, N.K. 2008. First record of occurrence of Boulenger’s anthias Sacura boulengeri (Heemstra, 1973), Family: Serranidae, in Indian waters. J. Mar. Biol. Ass. India 50(1): 69-73.

Preliminary study on the length-weight relationship of Sacura boulengeri (Heemstra, 1973) from Indian waters

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Preliminary study on the length-weight relationship of Sacura boulengeri (Heemstra, 1973) from Indian waters

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