近日，首都师范大学任东教授团队报道了在白垩纪中期新发现的群集石峨化石。2024年6月28日，国际知名学术期刊《国家科学评论》发表了这一成果。

研究人员描述了保存在缅甸白垩纪中期琥珀中的五种新的石峨化石，它们都以大的群集体的形式保存下来。这五个新种的单种特异性聚集可以根据翅形的形态学特征，以及性别二态性的特殊形式的存在而被明确地识别为群集。分子和形态数据的系统发育以及祖先特征重建和尖端年代分析的结果表明，群集可能在三叠纪时期作为毛翅目平面图的一个特征出现。

形态学证据显示，中生代的大多数食肉动物都是白天活动的，所以大部分夜间活动的石峨应该没有这种压力。系统发育还显示了古新世或始新世早期夜间捕食者蝙蝠的兴起，与石峨各分支群体的反复消失之间的相关性，揭示了蝙蝠捕食对重塑新生代毛翅目行为景观的潜在影响。

据悉，蜂群作为交配聚集的一种特殊形式，在蜉蝣目、双翅目和毛翅目昆虫中最为显著。从性别组成、特定的交配行为和成虫的功能形态专门化的角度来看，现存的毛翅目动物的群体行为已经得到了很好的理解，但是对这种群集行为进化的探索受到化石记录中可用实例的缺乏以及可靠区分少数群集能力的阻碍，这些群集是由于群体行为相对于其他分类学或行为因素的结果。

附：英文原文

Title: Swarming caddisflies in the mid-Cretaceous

Author: Wang, Jiajia, Engel, Michael S, Zhang, Weiting, Shih, Chungkun, Qiu, Rui, Ren, Dong

Issue&Volume: 2024-06-28

Abstract: Swarming, as a special form of mating aggregation, is most noteworthy in insects of the orders Ephemeroptera, Diptera, and Trichoptera. Swarming in extant trichopterans is well understood in terms of sex composition, specific mating behaviors, and functional morphological specializations of adults, but an exploration of the evolution of such aggregative behaviors is hampered by the dearth of available examples from the fossil record as well as the ability to reliably distinguish the few gatherings as the result of swarming relative to other taphonomic or behavioral factors. Herein we describe five new fossil species of caddisflies preserved in mid-Cretaceous amber from Myanmar, all preserved as large aggregations. Monospecific aggregations of these five new species can be positively identified as swarms based on morphological traits of wing shape, as well as the presence of particular forms of sexual dimorphism. Results of a phylogenetic reconstruction of both molecular and morphological data as well as ancestral-trait reconstructions and tip-dating analyses indicate that swarming was likely present in the Triassic as a feature of the trichopteran groundplan. Since most Mesozoic insectivorous predators were diurnal based on morphological evidence, largely nocturnal caddisflies would have been freed from such pressures. The phylogeny also shows a correlation between the rise of nocturnal bat predators from the Paleocene or early Eocene and the repeated loss of swarming from various clades of caddisflies, revealing the potential impact of bat predation on reshaping the behavioral landscape of Trichoptera during the Cenozoic.

DOI: 10.1093/nsr/nwae227

Source: https://dx.doi.org/10.1093/nsr/nwae227