Ontogenetic change in valve characters in three new species of Baffinicythere (Ostracoda, Crustacea) from Northern Japan
Ontogenetic change in valve characters in three new species of Baffinicythere (Ostracoda, Crustacea) from Northern Japan
复制标题
日本北部介形纲、甲壳纲三个新种的瓣膜特征的个体发育变化
DOI：
10.1017/s0022336000038385
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发表时间：
1996
影响因子：
1.4
通讯作者：
T. Irizuki
中科院分区：
文献类型：
--
作者：
T. Irizuki
贝氏介形虫属是一种北方高纬度海洋介形虫，包括四个种：B.howei Hazel、B.ishizakii新种、B.renetata新种、B.robusticostata新种。第一个物种只出现在北冰洋和北大西洋的晚上新世到最近的沉积物中。剩下的三个物种在日本北部的上更新世地层中含量丰富，这些地层产生冷水软体动物动物群。这三个新种的详细形态分析和古地理分布表明：1)网纹假单胞菌相对于其他两个种具有一些原始特征；2)白纹假单胞菌和罗布斯蒂亚种在个体发育尺寸增长速度方面似乎有不同的策略；3)左瓣轮廓可以分解为两个成分，个体发育形状变化和种间的种间差异；以及4)罗布斯蒂亚种入侵了网状双胞菌的生活区，并可能在晚更新世将其排除在外。大西洋种B.howei尚未从日本北部被记录。根据孔洞分布和网纹雕塑，网纹双胞菌和华威双胞菌的比较表明，双胞菌可能在白令陆地屏障被突破后迁徙到北极省，然后迅速进化为双胞胎杆菌。
The genus Baffinicythere is a northern high-latitude marine ostracode, which includes four species: B. howei Hazel, B. ishizakii new species, B. reticulata new species, B. robusticostata new species. The first species occurs only in late Pliocene to Recent sediments of the Arctic and northern Atlantic Oceans. The remaining three species are abundant in the Plio–Pleistocene formations of northern Japan, which yield cold-water molluscan faunas. Detailed morphological analyses and paleogeographic distribution of the three new species indicates that: 1) B. reticulata has some primitive characters relative to the other two species; 2) B. ishizakii and B. robusticostata seem to have had different strategies as regards rate of ontogenetic size increase; 3) the left valve outlines can be resolved into two components, ontogenetic shape changes and species-specific distinctions among the species; and 4) B. robusticostata invaded areas inhabited by B. reticulata and may have excluded it during the late Pleistocene. The Atlantic species B. howei has not been recorded from northern Japan. Comparisons of B. reticulata and B. howei, based on their pore distribution and reticulate sculptures, suggest that B. reticulata could have migrated to the Arctic Province after the Bering land barrier had been breached and then evolved rapidly into B. howei.
影响因子：
1.5
作者：
N. Ikeya;T. Cronin
通讯作者：
N. Ikeya;T. Cronin