中国九龙山组蜚蠊目川蠊属两性异型现象的研究
发布时间：2021年12月30日
2021年，国家自然博物馆与天津自然博物馆、首都师范大学研究人员共同研究我国内蒙古道虎沟地区的蜚蠊目蛇蠊科昆虫化石，其研究成果发表在著名的古生物学杂志Palaeontographica, Abteilung A。该项研究工作获得了北京市科学技术研究院“北科青年学者”项目(Grant No. YS201902)、天津市“五个一”项目、国家自然科学基金项目(31730087、41688103和32020103006)项目资助。
蜚蠊俗称蟑螂，项目研究的标本属于蜚蠊目蛇蠊科化石，生活在1.6亿年前的侏罗纪，已绝灭。通过对655件蜚蠊化石的整理研究，我们建立一新属两新种混天绫川蠊和宽边川蠊（Chuanblatta huntianlingensis，C. lata），属名因标本前胸背板的色斑呈现“川”字型而得名，模式种种名取自哪吒的法宝之一：混天绫（前翅色斑如同舞动的丝带一般）。论文对142只翅的数据分析得出：川蠊属具有两性异型现象，前翅翅长宽比小于3.4为雌性个体，长宽比大于3.4为雄性个体。雌雄个体除了前翅长宽比有差异外，其余头部、胸、腹部等特征都无显著差异。除了两性异型现象的讨论外，论文还对蟑螂休息时左右翅折叠情况进行了初步探讨。经过标本对比研究发现，蟑螂在休息时，可以左翅覆盖右翅，也可以右翅覆盖左翅。
Chuanblatta gen. nov. sexually dimorphic cockroaches of Raphidiomimidae (Blattaria) from the Jiulongshan Formation in China
Junhui Liang1, Ying Wang2, Chungkun Shih3，4, and Dong Ren3
1 Tianjin Natural History Museum, 31 Youyi Road, Hexi District, Tianjin, 300203, PR China
2 Beijing Museum of Natural History, 126 Tianqiao South St, Dongcheng District, Beijing, 100050, PR China
3 College of Life Sciences and Academy for Multidisciplinary Studies, Capital Normal University, 105 Xisanhuanbeilu, Haidian District, Beijing, 100048, PR China
4 Department of Paleobiology, National Museum of Natural History, Smithsonian Institution, Washington, DC 20013, USA
Abstract：
Six different families of predatory cockroaches have been reported hitherto for Blattaria. Among which the most distinct was the Raphidiomimidae spreading from the Early Jurassic to the Late Cretaceous. Up to date, seven genera and ten species of raphidiomimids have been documented worldwide, among which four genera with five species from the Middle Jurassic Jiulongshan Formation of Daohugou, China. Herein, we describe Chuanblatta huntianlingensis Liang, Wang, Shih et Ren gen. et sp. nov. and C. lata Liang, Wang, Shih et Ren gen. et sp. nov. from the same locality to highlight their sexual dimorphism that males with elongate forewings were statistically distinguished from females with relatively broad and round forewings. Furthermore, males had tergal glands for providing nuptial nutrition and both sexes bore distinctly raptorial forelegs and large subapical teeth and series of lateral and terminal teeth on mandibles, which are autapomorphies within Raphidiomimidae. Together with other 530 similar specimens in our collections, not covered in this study due to lack of preserved sexual organs or forewing length/width ratios, these Chuanblatta Liang, Wang, Shih et Ren gen. nov. cockroaches provided clear indication of strong dominance among all predatory cockroaches.
图片 1. 雌性宽边川蠊前胸背板A.照片B.线条图 比例尺= 0.5 mm
图片2.混天绫川蠊 A.B.模式标本雌性个体 C.D. 副模标本雄性个体 比例尺：2mm
图片3. 宽边川蠊 A.B.模式标本雌性个体 C.D. 副模标本雄性个体 比例尺：2mm