Graptemys pseudogeographica in the Upper Missouri River of the Northcentral United States
Graptemys pseudogeographica in the Upper Missouri River of the Northcentral United States
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美国中北部密苏里河上游的拟地龟
DOI：
10.2307/1563264
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发表时间：
1968
影响因子：
0.8
通讯作者：
R. L. Timken
中科院分区：
文献类型：
--
作者：
R. L. Timken
已知的Graptemys伪地理（Gray）的范围沿着密苏里河向上延伸了约250英里，其中一个标本代表了北达科他州的第一个州记录。采用金属丝漏斗捕集是一种有效的捕集方法。在密苏里河上游的假地理G.比报道的要丰富得多，在美国中北部的这个物种可能比人们认为的要丰富得多。据报道，该物种的最大尺寸创下了新的记录。关于大于8的海龟的性别比例和大小类别的种群数据。讨论了0厘米的鞘长。研究种群中存在较多的雌性种群，但性成熟雌与性成熟雄的比例约为相等，种群中最大的个体群是未成熟雌。确定雄性可能在体膜长度低于10厘米时性成熟；雌性性成熟发生在体膜长度为18厘米至19厘米。讨论了这些海龟的颜色和标记模式。
The known range of Graptemys pseudogeographica (Gray) is extended some 250 miles up the Missouri River and a specimen representing the first state record for North Dakota is reported. The use of wire funnel traps proved an effective method for collecting G. pseudogeographica. G. pseudogeographica is really much more abundant in the upper Missouri River than had been reported, and this species is probably much more abundant in the northcentral United States than has been believed. A new record for maximum size is reported for the species. Population data concerning sex ratios and size classes of turtles larger than 8. 0 cm plastral length are dis- cussed. A larger total number of females existed in the population studied, but the ratio of sexually mature females to sexually mature males was about equaL The largest group of individuals in the population was composed of immature females. It was determined that males probably became sexually mature at some plastral length below 10 cm; female sexual maturity occurs at a plastral length of 18 cm to 19 cm. Coloration and marking patterns of these turtles are discussed.