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Trabeculae: The muscular rod-like transverse ridgeswhich lend support to the protective membuwes.Vane: The thin, transparent lateral expansion of thegladius (Fig. 3).Water pores : The small openings leading io internalsmall pouches embedded in the oral surface of eachinterbrachial web between the arm bases in Cistopus.BRIEF DESCRIPTIONS OF EXPLOITED AND POTENTIALLYIMPORTANT CEPHALOPQDS OF INDUCUTTLEFISHESSepia pharaonis Ehrenberg, 1831(Plate I; A-F)This is the largest cuttlefish known from Indian seas.The body is ovoid in shape, broadest at about themiddle, slightly narrow at the anterior end and narrowerat the posterior part of the mantle. Body is robustwith muscular mantle and fins. The latter are broad,originate from the anterior margin of the mantle opening,have a slight forward projection anteriorly andextend along the entire margin of mantle ; the finsarewider near the posterior end. On the dorsal side theskin of mantle has numerous minute granular papillae,a series of small longitudinal faint ridges along theperiphery of the mantle and a narrow whitish line alongthe base of fins demarcating the mantle and the fins.The head is short and about as broad across the twoprominent eyes as long.The oral arms are long, subequal in length, with welldeveloped keels and with tapering ends. Dorsal armsare the shortest and the lateral arms are much compressed.The suckers on all arms are arranged in fourtransverse series ; suckers in the basal rows are largerand become gradually reduced in size towards the distalend, those at the tips very minute. The buccal membraneis thick and the lappets bear minute suckers atthe tips ; the dark coloured rostrum of the horny beakembedded in the buccal mass is seen in the middle.The tentacles are moderate in length and not verymuch longer than the body; the stem is thick andtriangular in cross section. The tentacular clubs arebroad, moderate in length being only about one fourthin dorsal mantle length; clubs are distinctly broaderthan those of Sepia aculeata and have a broad swimmingmembrane the end of which reaches a little beyond thebase of the club. The protective membranes on eitherside are narrow, extend slightly beyond carpus and notxmited at the base. Club suckers are unequal in sizeand very characteristic. Suckers of the carptB andCMFRi BULLETIN <strong>37</strong>dactylus portions are small; those in the middle partof manus are large in size and arranged in eig^t trans,verse series; about six suckers in the two me(U«iseries are much enlarged and prominent; tlK! suckerrings have wavy edge without denticulation.The left ventral arm is hectocotylized in males;the modified part is in the middle portion of tiie arm;basally 12-14 transverse smes M svaHaets of this armare normal in size, the next 4»10 sertes have normalventral rows of suckers but the dors^ Jeows of suckersare much reduced. These two rows u% separated bya thick ri(^ with grooves across. The females aremore robust than males; in the latter the mantle iscomparatively sUgbtly narrower.The cuttlebone is elon^te, broad and oval in shape,the surface is rugose in texture and has three longitudinalfaint ribs. The Chitinous outer edges are broad andyellowish brown in colour on the dorsal side of thecuttlebone.The ventral surface has a characteristic vnde, deep,longitudinal groove in the middle, running along theentire length of striated zone. The striae or growthlines are distinctly ' A * shaped. The inner cone isbroad in the middle and forms a plate-like prominentcallosity. Hie spine is short, stout and without keels.Males attain a maximmn ma&tle length of about430 mm and fenmles 330 mm (Roper et al., 1984).In fresh condition, the dorsal surface of the manfle,head and oral arms have dark brown transv(»:se stripes.This colouration is ^conspicuous in adult males. Thecolour pattern is variable.Sqpla aculeata Orbigny, 1848(Plate II; A-D)The mantle is broadly ovate in outline, width 3/5in length ; fins moderately broad and extend along theentire length of mantle. The head is large, about aslong as wide and narrower than the mantle opening.The oral arms are short, subequal in length in theorder 3.4.2.1. The dc^sal arms are rounded on theouter side, the lateral arms are keeled and the ventralones broad at the I^e with str(»ig swimming membrane.The buccal lapp^ bear a few minute sudcers withsmooth, chitinous rings. The arm suckers are unifcmnlyarranged in four rows Had bordered by protectivemembraros on either side. The left ventral arm inmale is he
about 12 rows of normal suckers followed by about6 transverse rows of very minute suckers, with a pitlikeexcavation in the middle of the modified portionand this is distinct in adult males.The tentacles are comparatively very long, slenderand keeled on the outerside; the stem is triangularin cross section. The tentacular clubs are long, about1/3 mantle length and slender but not much expanded;beyond the base of the club the protective membranesrun as two ridges on the oral side of the tentacularstem. The club suckers are minut«, subequal in sizeand arranged in about 10-12 longitudinal series inmales whereas females possess 13 or 14 series; thenumerous minute suckers on the tentacular dubs givethem a spongy appearance.Hie cuttlebone is elongate oval in shape with granularrough dorsal surface and has three low longitudinalribs; the chitinous margin is very narrow. The ventralsurface has a slightly convex striated zone anteriorlyand is concave at the posterior end where the posterioriimercone has a thick, rounded ridge in contrast tothe distinct plate-like form in S. pharaonis. On theventral surface, in the striated zone there is a longitudinalmedial ridge with a faint groove running medially;the striae are notched in the middle. The last loculusis short and its medial portion is slightly concave.Spine is small, strong and not keeled.The maximum size recorded is 230 mm (Voss andwaiiamson, 1971).The colouration of the dorsal mantle is very variableand consists of dififerent shades of gray or brown withwhite spots, streaks or patchies in varying patterns withnumerous chromatophores.Sepia brevimana Steenstrup, 1875(Plate III; A-E)The mantle is broadly ovate, its anterior marginprojects prominently in the middorsal plane into alobe which is very acuminate; the ventral anteriormargin is slightly emarginate in the middle. Theposterior end is also very much acuminate owing to thepresence of a long and pointed spine at the extremityof the cuttlebone. The fins are narrow, originate alittle posterior to the mantle margin and extendingalong the sides do not unite at the end. The acuminatcontour of the posterior end of the mantle is distinctlyseen on the ventral side. The head is as long as wideand eyes are prominent. The buccal membrane isseven lappetted.The ora arms are short, subequal and less than halfthe length of mantle. The arm suckers are quadriserialand small in size.Tentacles are slender and moderate in length. Clubsare very short and bear about eight oblique rows ofsmall suckers; enlarged suckers absent.The cuttlebone is very distinct, thin, flat and elongatelyovoid in outline. On the dorsal surface it is roughdue to the presence of numerous small tubercles whichform three definitive longitudinal ridges. On the ventralside, the cuttlebone is concave and a deep mediangroove is present in the striated zone. The striatedarea and the outer cone are separated laterally by abroad, smooth area on either side. The inner coneand its lateral limbs are distinctly pink coloured. Thespine is long, thin and slightly keeled. The cuttlebonesof male and female differ in shape. The cuttleboneof female is generally broader and more acuminatethan that of male. The tubercles on the dorsal sideare not prominent in the female.The maximum size attained by this species is95 mm.The dorsal surface of the cuttlefish is generally darkcoloured. The arms, neck region, sides and ventralsurface are whitish in fresh condition.Sepia elliptica Hoyle, 1885(Plate IV; A-D)The mantle is broadly ovoid in outline, stout andbroad at the mantle opening, not very much taperingat the, posterior end. The mid-dorsal projection,over the head inbetween the eye lobes, is sharp andprominent. The funnel is conical, short and does notreach the base of ventral arms. The head is shortbut broad with prominent eye lobes.Arms are short, stout, subequal in length, abouthalf in mantle length and have acuminate tips ; the armformula is 4.3.2.1. or 4.2.3.1. The suckers are arrangedin four uniform series on all the oral arms; they aremoderate in size and gradually become reduced towardsthe distal ends. The homy rims of the suckers arenot provided with distinct teeth but marked with notdies.The left ventral arm in male is hectocotilyzed. Thehectocotilyzed arm is normal for one third of its lengthfrom the base and the middle third of the arm is modifiedwith great reduction of the suckers especially the dorsalsuckers. The distal portion of the arm is not affectedby hectocotilyzation.26 CEPHALOPOD RESOURCES OF EEZ
Page 1 and 2: ulletin 37
Page 3 and 4: EXPLOITED AND POTENTIALLY IMPORTANT
Page 5 and 6: JVlitt II III IVRight Orol armsArm
Page 7 and 8: IVIII.ArmlengthFunrMi openingFunnel
Page 9 and 10: 6. Tentacular clubs very long, with
Page 11 and 12: omellii (Ferussac) and Nototodarus
Page 13: facilitate the two clubs to adhere
Page 17 and 18: CMFRI BULLETIN 37 E. G. SILAS ET AL
Page 19 and 20: CMFRl BuLETiN 37E. G. SILAS ET At.P
Page 21 and 22: slightly wider than long. The bucca
Page 23 and 24: stickeifs Crowding td give a ' sWab
Page 25 and 26: CMFRl Bui.TfTiN 37 E. G. SILAS ET A
Page 27 and 28: CMFRI Buu.ETiN 37 E. G. SILAS ET AL
Page 29 and 30: The Vade of the gladius Is broad at
Page 31 and 32: (ieep pit present on the ventral si
Page 33 and 34: CMFRI BULLETIN 37 E. G. SILAS ET AL
Page 35 and 36: CMFRI BULLETIN 37E. G. SILAS ET AL.
Page 37 and 38: There are two distinct tubercles ov
Page 39 and 40: REFERENCESABDUIXA, I. M. AND A. Z.
Page 41 and 42: DEES, LOLA T. 1961. Cephalopods: cu
Page 43 and 44: I8HI, M. 1977. Studies on the growt
Page 45 and 46: NARASIMHAM, K. A., G. SUDHAKARA RAO
Page 47 and 48: ROBSON, G. C. 1932. A monograph of
Page 49 and 50: t)NDP/FAO 1976b. Survey Results 197

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