北部湾红树林蟹类多样性初步研究

A Preliminary Study on Crabs Diversity for Beibu Gulf Mangrove

2012年7～10月,对北部湾沿海红树林12个采样点的蟹类标本进行了鉴定,共计39种,隶属于11科23属,其中Perisesarma eumolpe为国内新纪录种,米埔近相手蟹P.maipoensis为海南新纪录种;上述蟹类中,沙蟹总科种类最多,为8属20种,占所有种类的51.3%;其次为方蟹总科,共10属14种,占所有种类的35.9%;梭子蟹科与毛刺蟹科各2种,玉蟹科1种。北部湾红树林采样点蟹类多样性指数（H＇）变化范围为1.861～3.315,平均值为2.641,北海草头村多样性指数值最高（3.315）,最低为海南清澜港（1.861）;均匀度（J＇）变化范围为0.587～0.829,平均值为0.727,最高出现在北海草头村,最低为清澜港;丰富度（D＇）变化范围为0.892～1.972,平均值为1.488。各采样点间的相似性指数范围为0.087～0.632,其中大冠沙与雷州海角村的相似性值最大（0.632）,表现为中等相似;海南清澜港与北海草头村的相似性值最低（0.087）,表现极不相似。结果表明,方蟹和沙蟹是红树林区蟹类两个最大的类群,北部湾沿海红树林蟹类属于南海蟹类区系,主要由热带和亚热带暖水性种与广温广布种组成,蟹类的组成与分布受纬度、盐度、温度、红树林植被、底质、潮汐等综合因素的影响。

A field study had been conducted to identify the brachyuran crabs in the 12 sampling stations in mangroves of Beibu gulf during July to October 2012. A total of 39 species of brachyuran crabs belonging to 11 families, 23 genera were reported. Among these species, Perisesarma eumolpe was a new record in China, and P. maipoensis was a new record in Hainan; Ocypodoidea （ including 8 genera and 20 species） was accounted for 51.3%, and Grapsoidea （ 10 genera and 14 species） accounted for 35.9% of all species; There were also two species of Portunidae and Pilumnidae, respectively; and one species belonging to Leucosiidae. Among the 12 sampling stations, the diversity index of crabs （H＇） ranged between 1. 861 -3. 315, with a mean of 2. 641, the highest Pielou index value （ 3. 315 ） was observed in Beihai Caotou village, while the lowest （1. 861 ） was in Hainan Qinglan Harbor; Pielou index （J＇） ranged between 0. 587 -0. 829, with a mean of 0. 727, the highest was observed in Beihai Caotou village, while the lowest was in Qinglan Barbor ; Margalef index （ D＇ ） ranged between 0. 892 - 1. 972 with a mean of 1. 448. The similarity index ranged between 0.087 - 0. 632, the maximal value （0.632） was observed in both Daguansha and Leizhou Haijiao village ; The lowest similarity value （ 0. 087 ） was observed in both Hainan Qinglan Barbor and Beihai Caotou villege. The results showed that Ocypodoidea and Grapsoidea were the largest groups, and the Beibu gulf coastal mangrove crabs belonged to the South China Sea crab fauna which was composed of tropical and subtropical warm water species and wide temperature species. The composition and distribution of the crab could be influenced by the different mangrove vegetation, latitude, salinity, temperature, substrate, tidal and other comprehensive factors.