Gore Robert H
Biol Bull. 1973 Feb;144(1):132-150. doi: 10.2307/1540151.
The complete larval development from hatching through megalopal stage is described and illustrated for Pachycheles monilifer, a shallow water porcellanid crab. The development at room temperature (27.8° C) under laboratory conditions consisted of a prezoeal stage of approximately one hour duration, two zoeal stages of approximately five and six days duration, respectively, and a megalopal stage of about eight days duration. The entire larval/postlarval portion of the life cycle is completed under the conditions described herein in approximately three weeks. The zoeal and megalopal stages of P. monilifer were compared with larvae known from two other western Atlantic species, and two species each from the eastern Pacific and Indo-Pacific oceans. As might be expected, larvae of the genus are quite similar in many respects, and difficulty may be encountered in separating them at the specific level. However, certain morphological features are recurrent in the zoeal stages and may be indicative at the generic level; among these are the presence of three spines on the antennal exopodite, four setae on the maxilliulary endopodite, and the hook-like spinules on the first two elongate plumose setae of the telson. A provisional synopsis is provided utilizing the most salient features occurring in all known Pachycheles larvae as an aid in recognizing such larvae, at least at the generic level, in the plankton.
本文描述并展示了浅水瓷蟹——念珠厚螯蟹从孵化到大眼幼体阶段的完整幼体发育过程。在实验室条件下，室温（27.8°C）下的发育过程包括：持续约1小时的前溞状幼体阶段、分别持续约5天和6天的两个溞状幼体阶段，以及持续约8天的大眼幼体阶段。生命周期中整个幼体/后期幼体部分在本文所述条件下大约三周内完成。将念珠厚螯蟹的溞状幼体和大眼幼体阶段与另外两种西大西洋物种、两种东太平洋物种和两种印度-太平洋物种的已知幼体进行了比较。正如预期的那样，该属的幼体在许多方面非常相似，在特定水平上区分它们可能会遇到困难。然而，某些形态特征在溞状幼体阶段反复出现，可能在属的水平上具有指示性；其中包括触角外肢上有三根刺、小颚内肢上有四根刚毛，以及尾节的前两根细长羽状刚毛上有钩状小刺。利用所有已知念珠厚螯蟹幼体中出现的最显著特征提供了一个临时概要，以帮助在浮游生物中识别此类幼体，至少在属的水平上。
