大治河河口无齿螳臂相手蟹生长和成熟的研究(英文)

无齿螳臂相手蟹是长江口潮间带和潮上带的优势种之一,具有重要的生态功能。为探求无齿螳臂相手蟹不同阶段的异速生长和成熟状况,于2009年10月至2010年9月期间采集样本,通过聚类和分段线性回归等分析方法对雌雄蟹头胸甲、螯、腹部等形态数据进行分析,建立区别不同生长阶段的判别函数并用逻辑斯蒂回归估计其50%形态成熟点。结果如下:雌雄蟹50%形态成熟点分别为头胸甲宽18.22mm和16.36mm。雄蟹的螯宽和雌蟹的腹宽均表现出明显的异速生长;根据相对生长率的不同,雄蟹异速生长可分为三个阶段,雌蟹分为两个阶段;不成熟的雄蟹异速生长拐点发生在壳宽11.78mm,不成熟和成熟雌蟹腹部在壳宽13.04～18.64mm范围内重叠。同时研究了50%的生理成熟大小,雌雄成熟大小分别为17.50mm,17.20mm。雄性形态成熟大小小于生理成熟大小,而雌性则相反。     

基于线粒体COI和16S rRNA基因的中国沿海相手蟹系统发育研究

相手蟹科的诸多种类因其形态极其相似成为方蟹总科分类中疑问较多的一个类群。通过对中国沿海相手蟹线粒体COI和16S rRNA基因序列进行分子系统发育分析，结果表明14种相手蟹COI和16S rRNA基因序列之间差异分别为5.7%～14.5%和1.5%～12.1%，均达到了种间差异水平。构建的系统发育树显示，14种相手蟹分别为独立有效物种，但分属于拟相手蟹属和近相手蟹属的4种拟相手蟹和3种近相手蟹，没有分别形成2个独立的支系，而是混合聚成一大支系。而属于螳臂相手蟹属的无齿螳臂相手蟹则首先与属于中相手蟹属的中华中相手蟹聚成一支，再与红螯螳臂相手蟹聚为一大支，表现出与形态分类的不一致。错综复杂的分子系统关系预示着相手蟹类为多系起源，也表明它们之间的种间关系乃至于属间关系尚有诸多问题有待进一步厘定。     

淡水经济虾类红螯螯虾(Cherax quadricarinatus)不同规格肌肉营养组成及表型性状分析

红螯螯虾(Cherax quadricarinatus)又名澳洲淡水龙虾,属于名贵的淡水经济虾类,对环境条件耐受性强,出肉率明显高于其他品种。分别对4种体重规格红螯螯虾肌肉营养组成和表型性状进行系统性分析,采用国标法测定肌肉粗蛋白、粗脂肪及粗灰分含量,采用氨基酸分析仪测定肌肉氨基酸含量及组成,采用气相色谱法测定肌肉脂肪酸组成。结果表明,红螯螯虾全长和体长显著增加(20～80g组),雌虾全长和体长显著高于雄虾(60～80g组);头胸甲长和头胸甲宽以80～100g组雄虾最大,在60～80 g组中雌虾显著高于雄虾,头胸甲高在规格60 g以上不再有显著变化;腹部肌肉重以80～100 g组雄虾最大,但与60～80 g组雌虾无显著性差异,各组雌虾出肉率显著高于雄虾(P<0.05)。肌肉粗脂肪含量以80～100 g组雄虾最高,40～60 g组雄虾最低(P<0.05);肌肉灰分含量小规格20～40 g组较高,40～60 g组雌虾最低。红螯螯虾肌肉氨基酸(AA)、总氨基酸(TAA)、必需氨基酸(EAA)和呈味氨基酸(DAA)均随规格变大而逐渐降低;在氨基酸评分(AAS)模式下,各组第一限制性...     

大通湖中华绒螯蟹(Eriocheir sinensis)品质分析与评价

本文对湖南省大通湖所产中华绒螯蟹(Eriocheir sinensis)的成蟹,按商业品级和雌、雄,测定了其各部分含量和各项营养成分。该湖所产河蟹符合正宗中华绒螯蟹青背、白肚、金爪、黄毛的大闸蟹形态特征。肌肉、肝脏及性腺三大可食部分共占体重的38.13%,壳、鳃、胃及心脏四大非可食部分共占体重的51.56%,另有10.31%为血淋巴和组织液;3个指标分别比阳澄湖大闸蟹36.72%、53.26%、10.02%相差1.41、1.70、0.29个百分点。大通湖一级、二级商品蟹可食部分各高出阳澄湖5.29%和2.43%,营养成分中蛋白质含量高于阳澄湖6.83%和3.60%,9项微量元素总和与阳澄湖相当,17种氨基酸总和比阳澄湖高6.78%和4.20%,鲜味氨基酸比阳澄湖高10.69%和4.94%。但以上各种指标雌、雄蟹之间均存在差异,且微量元素和氨基酸组成方面雄蟹优于雌蟹。     

中国海倒颚蟹属（甲壳动物亚门：十足目：豆蟹科）两新记录种

长期以来,中国海倒颚蟹属仅记录一种,即渤、黄、东海底栖动物常见种异足倒颚蟹AsthenognathusinaequipesStimpson,1858。作者对中国科学院海洋生物标本馆收藏的采自中国海的全部倒颚蟹属标本进行系统研究后共发现除该种外还有以下2种,为中国海的新记录:宽身倒颚蟹AsthenognathusgallardoiSer埁neandSoh,1976和六角倒颚蟹AsthenognathushexagonumRath-bun,1909,均采自南海北部。异足倒颚蟹为中国北方和东部海域常见种,但未见于南海。六角倒颚蟹与异足倒颚蟹形态上较相似。两者差异在于六角倒颚蟹头胸甲六角形,后缘约与额-眼眶缘等宽,背面有2对凹陷,后侧缘有2条颗粒脊,而异足倒颚蟹头胸甲后缘约为额-眼眶缘宽的1.5倍,背面仅有浅横沟。宽身倒颚蟹与其他两种形态差异较大,头胸甲宽约为长的1.9倍。     

罗氏沼虾(Macrobrachium rosenbergii)雌雄虾不同形态阈值性状的遗传变异分析

氏沼虾(Macrobrachium rosenbergii)雄虾有四种不同形态:小雄虾(SM)、橙色螯(OC)、蓝色螯(BC)和老蓝色螯(OBC)雄虾;雌虾分为四种:性腺未发育(IF)、性腺成熟(MOF)、抱卵(BF)和已产幼体(SF)的雌虾。已有研究表明不同形态的雌雄虾的体重存在显著差异,为了探讨是否可以对罗氏沼虾不同形态雌雄虾所占比例开展选择来间接提高产量,首次对上述性状的遗传参数及其与收获体重的遗传相关进行了评估。记录了罗氏沼虾核心育种群体两代共计40 935尾个体的形态和体重信息,使用父母本育种分析模型和阈值统计模型估计不同形态二分类(0和1)阈值性状在世代间和世代内的遗传参数,并使用两性状模型估计其与体重性状的遗传相关。方差组分估计结果表明,雄、雌虾不同形态阈值性状的遗传力估计值分别为0.08~0.12和0.04~0.22。雄虾形态OC、BC阈值性状与收获体重间为低度正相关(0.01~0.43)。雌虾形态IF、BF、SF阈值性状和收获体重性状之间为中等程度相关(–0.61~0.53)。在我国土塘养殖模式下,罗氏沼虾雌雄个体不同形态阈值性状存在可利用的加性遗传变异,具有较大的改良空间;选择OC形态雄虾并增加其在育种群体中比例,并不会降低其生长速度;选择IF形态雌虾并增加其在育种群体中的比例,可能会降低其生长速度。     

海蟹三珍

海蟹的种类不少,常见而且经济意义大的有青蟹、梭子蟹和鲟。青蟹,也称锯缘青蟹,头胸甲短而较宽,两侧无长棘,几近椭圆形,青绿色,大个体通常有10厘米长,14厘米宽。螯足不对称,较粗壮,第四对步足扁平似桨,适于游泳。青蟹喜食腐肉,也捕食藻类,栖息于温暖而低盐度的浅海,在有海水渗入的河涌沟洼亦可长期生活,青蟹为重要食用海蟹之一。味清甘鲜美,但肥瘦不同,优次有别。它脱壳后一段时间比较瘦,称水蟹;此后肉渐丰满,肥实的雄蟹和未受精的雌蟹,称肉蟹;而受精后的雌体,经育肥卵巢成     

日本沼虾（Macrobrachiumnipponensis）形态性状对体重的影响效应

选取日本沼虾5月龄同生群雌、雄虾各90尾,分别测量其体重、体长、头胸甲长、胸宽、胸高、腹节长、腹节宽、腹节高、尾节长、尾节宽、尾节高、眼窝距、额剑长等13个表型性状,并采用相关分析、通径分析和偏回归分析等方法定量研究了雌、雄个体形态性状对体重的影响效应。结果表明：（11雌、雄测定群体各形态性状测量值间均存在显著的性别差...     

螃蟹的挑选与食用

随着人们物质生活水平的提高,螃蟹,已爬进寻常人家的菜篮。螃蟹肉质鲜美,蟹黄肥厚,营养丰富,是好多人爱食的海产佳肴。尤其是野生蟹,其口味更上一层。螃蟹是美食,但挑选和食用却很有学问。挑选螃蟹时一定要仔细观察,精心选择鲜活膘肥的。挑送时主要有“五看”:一看蟹壳。壳背呈墨绿色,一般都体厚坚实,呈黄色的,大多较瘦弱;二看肚脐。肚脐凸出来的,一般都膏肥脂满,凹进去的,大多是膘水不足;三看螯足。螯足上刚毛丛生的,一般都膘足老健,反之,是体软无膘;四看雌雄。俗话说,农历八月挑雌蟹,九月过后选雄蟹,是有个中道理的。因为雌雄螃蟹分别在这两个时期性腺成熟,营养和滋味最佳;五看活力。若将螃蟹翻转身来,腹部朝天,能够迅速用螯足弹转翻回的,活力强,可保存,不能翻回的,活力差,存放时间短。通过这“五看”,就能把好蟹选出来。其次是食用。食用的门道很多。民间有“生吃螃蟹活吃虾”之说。因此,有人喜欢生吃螃蟹。其实,生吃螃     

Sex‐related differences in size,function and regeneration of the major cheliped in the hermit crab Pagurus filholi

Pagurus hermit crabs have a well‐developed right cheliped (major cheliped) and in some species the major cheliped of males is longer than that of females. This paper describes sex‐related differences in major cheliped length and regeneration pattern of the major cheliped in the hermit crab Pagurus filholi. We also examined the function of the major cheliped in male–male competition. Major cheliped length of males was longer than that of females in P. filholi. Males regenerated larger chelipeds than females at the first molt after experimentally induced autotomy. Body size growth in males of the regeneration group was less than that in intact males of the control group while there was no significant difference in body size growth of females between regeneration and control groups. Major cheliped length was included in the best model to explain the outcome of male–male competition and thus sexual selection appears to be a causative factor in the sex‐related difference of the major cheliped length. Sex‐related differences in the regeneration pattern may reflect differences in evolutionary pressures on males for large major chelipeds and females for large body size.     

Growth rate in a population of the freshwater crayfish,Paranephrops planifrons white

Observations on growth increments at moult in a population of freshwater crayfish, Paranephrops planifrons, were made from periodic recaptures of marked animals. The growth increment increased with increasing size of crayfish up to about 20 mm carapace length (65 mm total length) after which a slight decrease was evident. By analysis of the size distributions in samples taken at different times of year it was found that four to five year classes were normally present. Growth of these age components could be followed through consecutive samples. Mean size at leaving the parent in December was 3.5 mm, after one year 11.4–11.8 mm, after two years 18.2–19.3 mm, after three years 22.1–23.8 mm, and after four years 26.7–29.6 mm, all sizes quoted as carapace lengths. After sexual maturity growth in the females was less than in the males. The number of moults completed by each year class was found by relating data on growth increment per moult to growth shown in consecutive quantitative samples. In the first year of life nine moults were completed, in the second year three moults, in the third year two moults, and in the fourth one moult. Independent data on moult frequency recorded from marked crayfish agreed well with these figures.     

Comparison of the population structure and life-history parameters of Diplodus capensis (Sparidae) in exploited and unexploited areas of southern Angola

Blacktail seabream Diplodus capensis were sampled from proximate (10 km apart) exploited and unexploited areas in southern Angola to compare their population structures and life-history parameters. Females dominated the larger size and older age classes in the unexploited area. In the exploited area the length and age frequency distributions were more equitable, but there was a lack of large and old individuals in this area due to the selective nature of fishing gear. Growth zone deposition rate was validated as being annual using mark-recapture of chemically injected (oxytetracycline) fish. In the unexploited area, females attained larger sizes and greater ages than males; however, growth and longevity were more equitable between the sexes in the exploited area. Length- and age-at-50% maturity were similar between the sexes in both areas. The sex ratio was heavily female-skewed (1:4.7) in the unexploited area but less so in the exploited area (1:2.2). Although the growth curves were significantly different for fish between areas, this was likely due to a reduction in longevity rather than a physiological change in growth. The length- and age-at-50% maturity was also similar between areas, indicating that this species either does not have the ability to respond to exploitation through physiological change in these life-history characteristics, or that the current level of exploitation is not high enough to elicit such a response. However, the female dominance in the smallest size class in the exploited area (compared to the unexploited area) indicated that a threshold may have been reached, and that this species responds to exploitation by increasing the relative number of fish that mature as females.     

Reproductive pattern and egg development of the deep-sea crab Paromola cuvieri (Brachyura,Homolidae) around the Canary Islands (NE Atlantic)

This work investigated the biology of Paromola cuvieri in the Atlantic Ocean, including reproductive patterns, sex structure, depth distribution and egg development. Females were more abundant than males, mainly at depths greater than 600 m. Males were dominant in size classes larger than 110 mm carapace width (CW), especially over 120 mm, for which only males were observed. The mean length of both sexes decreased with depth. P. cuvieri appears to have continuous reproduction throughout the year. Large females tend to spawn mainly between summer and winter, but smaller females spawn during the summer. Four maturity categories were identified based on the ovary colour, and these categories were histologically validated. Three categories of testes were identified according to their colour and morphology. Sexual maturity was estimated at sizes between 71.6 and 74.0 mm CW for females and at 91.0 mm CW for males. The relative growth showed changes along the ontogeny, at 73.6 mm CW (females) and 91.3–92.2 mm CW (males). Egg development appears to not be completely synchronous, and two colour patterns can be observed simultaneously. Four stages of egg development were found: eggs undivided and fully filled with yolk in orange egg masses; eggs with a free region of yolk visible in orange or red egg masses; embryos with slightly pigmented, crescent-shaped eyes in brown egg masses; and embryos with visible pigmented structures, enlarged eyes, segmented appendages and abdomen in brown egg masses. The mean number of external eggs carried by females in stage I was estimated to be 315,753±19,267. Three species of barnacle were observed on the exoskeleton: Poecilasma aurantia, Poecilasma crassa and Heteralepas microstoma (Cirripedia, Thoracica).     

Size at first maturity in females of the spiny lobster jasus verreauxi (Crustacea: Decapoda: Palinuridae)

The carapace length and total length size at first maturity in females of Jasus verreauxi (H. Milne Edwards, 1851) has been investigated by a detailed study of (a) the detection of the smallest size class with external eggs, and (b) the incidence of egg‐carrying females per size‐class interval. For the study 834 females were measured and examined at Spirits Bay, New Zealand, during mid October and late December 1966. The specimens ranged in carapace length from 12.0 cm to 23.9 cm, and in total length from 29.0 cm to 56.9 cm.

The results of the study show clearly that the females reach first maturity at a carapace length or a total length larger than the present minimum legal size, i.e. a carapace length of 10.2 cm (4.02 in.), or a total length of 25.4 cm (10.0 in.). No mature females were found less than 13.5 cm carapace length, or 32.0 cm total length. First maturity was attained by the majority (50% or more) of the J verreauxi females at a carapace length of 15.3 cm or larger, or at a total length of 38.0 cm or larger.

No undersized (smaller than the minimum legal size) females were present in the collections—yet 10.3% of the specimens were found to be immature. Immature females ranged in carapace length from 12.0 cm to 16.9 cm, or in total length from 29.0 cm to 41.9 cm. Being larger than the minimum legal size, all of the immature specimens examined were “harvested"—without having reached first maturity. It appears therefore that the stocks of small, immature female J. verreauxi are not protected by the present New Zealand minimum size regulation.     

Reproductive Biology of Liocarcinus puber and L holsatus (Decapoda, Brachyura, Portunidae) from the Gower Peninsula, South Wales

Abstract. Routine monthly samples of the commercially important portunid crab Liocarcimtx puber and the sympatric but ecologically separated L. holsatus were collected from the waters and shores around the Gowcr Peninsula, South Wales, between November 1983 and September 1985.
The pubertal moult in L. puber occurred at 38 mm CW (carapace width) (females) and 42 mm CW (males). In L. holsatus this occurred at 17 mm (females) and 18.5 mm CW (males). The median size of ovigcrous females was 49.2 ± 6.7 mm CW in L. puber and 26.5 ± 2.0 mm CW in L. holsatus.
Moulting and copulation occurred between spring and autumn, the moulting period of males being earlier than that of the females. Ovigcrous L. holsatus were recorded throughout the year, with highest proportions between February and April. L. puber were ovigcrous mainly between January and March; none was recorded between September and November. The number of eggs of the wild brood (range: 39,000–280,000 for L. holsatus and 40.000–262.000 for L. puber ) was related to female body size as y = 3.099.51 c^0.1126x, r = 0.90, n = 21 and y = 6,335.98 c^0.051x, r = 0.88, n = 23, respectively, where y = number of eggs and x = carapace width (mm).
Following successful copulation, females of both species were able to spawn more than once during an intcrmoult period.     

Reproductive biology of spiny lobster Panulirus regius from the north-western Cape Verde Islands

Green (spiny) lobsters Panulirus regius were obtained by diving at Cape Verde, West Africa, during three sampling periods: May–November 2001, April–December 2002 and April–June 2003. Totals of 429 male lobsters and 423 females (852 in all) were caught. Half the females were ovigerous throughout the sampling periods. Female estimated size-at-50% maturity was 87.9mm carapace length (CL). Brood size and egg developmental stage were examined in 68 ovigerous females. The relationship between brood size (BS, thousands of eggs) and CL (mm) was BS = 1.59CL^2.77. Females in the size-class 100–105mm and 115–120mm CL produced half the eggs in the population. Based on these results, an increase in the minimum landing size is proposed. The potential implementation of a maximum landing size is discussed.     

巨螯蟹属在中国东海的新记录

本文报导了巨螯蟹属在我国东海为首次记录。记述一种巨螯蟹(原名高脚蟹)。     

Cannibalistic interactions of juvenile mud crabs Scylla serrata: the effect of shelter and crab size

In the culture of mud crab Scylla serrata, cannibalism is often the greatest cause of mortality. A laboratory study was conducted to compare the influence of size class differences and shelter on cannibalism and limb loss in juvenile mud crabs (20–70 mm internal carapace width; ICW). Four size classes of juvenile crab (A: 21–30 mm, B: 31–40 mm, C: 41–50 mm and D: 51–70 mm ICW) were tested in all possible combinations using four different substrata with varying degree of shelter (seaweed, plastic strings, bamboo tubes and open sand substratum) in 48 h trials. Results suggest that cannibalistic interactions are heavily influenced both by size differences of crabs and the availability of shelter. Cannibalism on the smallest size class (20–30 mm ICW) increased about 10 times in the presence of the largest crab (51–70 mm ICW) compared with treatment with only same-size crabs (control treatment). Shelter provided little refuge for the smallest crabs, whereas cannibalism in larger size classes decreased by >50% in all the shelters compared with the sand substratum. The findings suggest that both size-grading and provision of shelter could minimise cannibalism in the culture of mud crabs.