Studies on diversity of Cretaceous vascular plants and their symbiotic organisms

在2002财政年度，1到北海道进行了一次实地收集之旅，在那里收集了大量含有植物碎片的结核。由于很少有材料可以满足本研究的目的，我继续分类鉴定以前收集的可能裸子植物的果实，并进一步寻找化石植物组织中的真菌和节肢动物化石。虽然我找不到任何真菌或节肢动物，但果实本身被确定为裸子植物的一个新物种，可以被分配到一个新的目的。作者从一位业余收藏家那里获得一个蕨类根茎化石，并将其命名为桫椤科一新种，该种隶属于Dicksonia属。这两个新的分类群将在其他地方描述。我继续显微镜下寻找化石真菌在过矿化化石，主要是木材，收集自白垩纪的五夏之浦系列，熊本县，群马县西林统岩手县久地和谷市系列，一 ...更多信息 位于北海道的Yezo集团。木材腐朽菌普遍存在于破坏组织中。这表明木材腐朽菌在白垩纪陆地生态系统中的广泛活动。还发现重要的是主要发生的VA（泡状丛枝）mycorrhiza的根皮层的白垩纪树蕨Tempskya。VA菌根缺席的任何桫椤蕨类植物的根系，这也表现出树的习惯。这可能是互惠VA真菌使Tempskya可能有效地吸收无机材料。这种互惠关系的崩溃可能导致Tempskya在白垩纪末灭绝。在北海道的化石中寻找节肢动物，在两个不同的器官中发现了3种不同的昆虫。在裸子植物的果实中发现了一种昆虫，属于啮虫目。另外两个存在于裸子植物枝条的变形组织中，这可能是昆虫的胆汁。一个是保存不好的幼虫，难以分类鉴定，另一个是一个小的成年人，巢在一个圆形的结构，可能是由自己。成虫的形态与Polyphaga的Staphilinoidea相似。这些发现为白垩纪生态系统中昆虫利用植物组织的不同方式提供了证据。少

In the fiscal year of 2002, 1 carried out a field collection trip to Hokkaido, where a large number of nodules containing plant fragments were collected. Since there were few material that can fit the purpose of this study, I continued taxonomic identification of a previously collected fructification of possible gymnosperm, and further search of fossil fungi and arthropods in the fossil plant tissue. Although I could not find any fungi nor arthropods, the fructification itself was identified as a new species of gymnosperm that can be assigned to a new order. A fossil tree fern rhizome donated from an amateur collector was designated as a new species of the Cyatheaceae, which is attributable to the genus Dicksonia. Both new taxa will be described elsewhere.I have continued microscopical search of fossil fungi in permineralized fossils, mainly woods, collected from the Cretaceous of Goshonoura Series, Kumamoto Pref., Sebayashi Series, Gunma Pref., Kuji and Taneichi Series, Iwate Pref., a … More nd Yezo Group, Hokkaido. Wood decaying fungi were commonly found in disorganizing tissues. This shows wide activity of wood decaying fungi in the Cretaceous terrestrial ecosystem. Also found important was the predominant occurrence of VA (vesicular-arbuscular) mycorrhizae in the root cortical layer of a Cretaceous tree-fern Tempskya. The VA mycorrhizae were absent in the root system of any Cyatheaceous ferns, which also exhibit a tree habit. It is likely that mutualistic VA mycorrhizae made Tempskya possible to effectively absorb inorganic materials. Collapse of this mutualistic relationship might have causec extinction of Tempskya by the end of the Cretaceous.Search of arthropods in permineralized fossils from Hokkaido resulted in findings of 3 different insects in two different organs. One insect was found in a gymnosperm fructification, and was attributed to the Psocoptera. Other two existed in a deformed tissue of a gymnospermn twig, which is a possible insect gall. One is a poorly preserved larva hard to taxonomically identify, and the other is a small adult that nested in a round sturucture probably made by itself. The adult form was comparable to the Staphilinoidea of Polyphaga. The findings provided evidence of varying ways of use of plant tissues by insects in the Cretaceous ecosystem. Less