宁夏晚泥盆世胴甲鱼类一新种及其古动物地理意义

IVPP-IR > 硕博论文

	宁夏晚泥盆世胴甲鱼类一新种及其古动物地理意义
其他题名	A new species of antiarchs from Upper Devonian of Qingtongxia, Ningxia and its Paleobiogeographic significance
	贾连涛
学位类型	硕士
导师	朱敏
	2008-02-01
学位授予单位	中国科学院古脊椎动物与古人类研究所
学位授予地点	古脊椎动物与古人类研究所
关键词	晚泥盆世胴甲鱼类宁夏系统发育分析古动物地理
摘要	本文记述了在宁夏青铜峡市石峡沟上泥盆统中宁组中发现的胴甲鱼类一新种¬¬¬¬¬——小刺吉尔吉斯鱼（Kirgisolepis spinosa sp. nov.）。本文所描述的标本（古脊椎所标本登记号V 14714）保存状况良好，头甲、躯甲和胸附肢呈自然联接状况保存，标本长度在12 cm左右。头甲位于后松果片之前部分缺失，躯甲保存近完整，左侧胸附肢以内核形式保存，右侧胸附肢近节完整，远节局部缺失。头甲骨片界线清晰，但骨片间覆压关系不清。中颈片呈规则的多边形，略方，不完全包裹后松果片。后侧角位置靠前，关节缘短，朝侧后方。躯甲背壁隆起，腹壁扁平。前中背片呈不规则六边形，前后缘均宽，前缘稍宽于后缘。侧角发育，将前中背片分为前后两部分，最宽处位于两侧角之间的连线上。前中背片的前侧缘由前向后先覆压前背侧片而后又为后者所覆压。背中棘高大侧扁，由前、后中背片共同组成。背侧嵴十分发育，自前背侧片前缘处向后逐渐隆起，延伸至近后背侧片后缘。前腹侧片右侧压左侧，中腹片菱形。腹侧嵴显著发育，自前腹侧片中部向后逐渐隆起，嵴部纹饰特化为刺状。胸附肢分节，近节明显长于并宽于远节。胸附肢近节两侧缘遍布小刺，远节仅在近端内侧发育有一小刺。胸附肢第一、二背中片与第二中缘片、侧缘片点状接触。胸附肢展开后远端达躯甲后缘。经形态学和分支系统学研究，本文将宁夏材料归入吉尔吉斯鱼属（Kirgisolepis），代表了该属一新种。 Panteleyev（1992）建立吉尔吉斯鱼属，属型种为卡拉巴塔吉尔吉斯鱼（K. karabaltaensis），并将其归入沟鳞鱼科。本文基于新材料对吉尔吉斯鱼的属征进行了修订与补充。修订后的属征有：中颈片不完全包裹后松果片；前中背片前侧缘由前向后先覆压前背侧片而后又为后者所覆压；背中棘由前、后中背片两部分组成；胸附肢分节，第一和第二背中片有接触，近端两侧缘遍布小刺；感觉沟系统发育，头部中央感觉沟、上枕联合点线沟和躯甲后背斜感觉沟均发育。吉尔吉斯鱼的纹饰和感觉沟系统接近沟鳞鱼科，而头部骨片形状和相邻骨片间的接触关系以及胸附肢骨片排列型式等接近星鳞鱼科。胴甲鱼类分支系统学研究结果表明，吉尔吉斯鱼应属星鳞鱼科。在泥盆纪全球古地理重建中，吉尔吉斯鱼两个种的产地分属哈萨克斯坦板块和祁连-柴达木板块（或华北板块），两地脊椎动物群与植物群组合具有很强的可比性。新种的发现进一步指示着哈萨克斯坦板块与华北板块在泥盆纪古动物地理上的联系。
其他摘要	A new species of antiarchs¬ (Kirgisolepis spinosa sp. nov.) is described from the Zhongning Formation (Late Devonian) of Shixiagou, Qingtongxia, Ningxia, northwestern China. As the second species of Kirgisolepis, it extends the geographic distribution of Kirgisolepis from Kirghizia to northwestern China, and suggests the biogeographic proximity between Kazakhstan Plate and Qilian-Qaidam Terrane (or North China Plate) during the Devonian. The holotype (IVPP V14714) of the new species from Ningxia is nearly complete, with the head-shield, trunk-armour, and the pectoral appendages in their natural association, total length estimated at about 12 cm. The nuchal plate does not separate the postpineal plate from the lateral plate. The central sensory line groove and supraoccipital cross-commissural pit-line groove are developed. The anterior median dorsal plate overlaps the anterior dorsolateral plate anteriorly and is overlapped by the latter posteriorly. The dorsal median spine of trunk armour is composed of anterior and posterior median dorsal plates. The anterior and posterior oblique dorsal sensory line grooves are present. The dorsal lateral and ventral lateral ridges are developed to form high ridges with spinlets. The first and second dorsal median plates of the pectoral appendage contact with each other, and separate the second mesial and lateral marginal plates. Panteleyev (1992) placed Kirgisolepis within the family Bothriolepididae. The re-examination of his text-figures and plates suggests that Kirgisolepis should not be assigned to the Bothriolepididae. The exoskeleton of Kirgisolepis shows the co-occurrence of the features characterizing both asterolepiform and bothriolepiform antiarchs. Kirgisolepis is similar to the Bothriolepididae in its sensory line groove system, but resembles very much the Asterolepididae in the proportions of the nuchal plate, its contact relationships with the other skull-roof plates and the bone pattern of the pectoral appendage. The cladistic analysis suggests its phylogenetic position within the family Asterolepidae. Few details regarding the pectoral appendage of Kirgisolepis were known. The diagnosis of Kirgisolepis is modified and supplemented by the new data from Ningxia, especially those on the pectoral appendage of the new species.
页数	62
语种	中文
文献类型	学位论文
条目标识符	http://119.78.100.205/handle/311034/1684
专题	硕博论文
推荐引用方式 GB/T 7714	贾连涛. 宁夏晚泥盆世胴甲鱼类一新种及其古动物地理意义[D]. 古脊椎动物与古人类研究所. 中国科学院古脊椎动物与古人类研究所,2008.

条目包含的文件
文件名称/大小	文献类型	版本类型	开放类型	使用许可
10001_20042800541400（3099KB）			开放获取	--	请求全文