Untitled

2010010418
amphiaspids 分 类 多 样 性 的 演 化 以 及
在 有 利 生 态 条 件 下 灭 绝 的 原 因 = Evolution
of taxonomic diversity in amphiaspids
(Agnatha, Heterostraci: Amphiaspidiformes)
and the causes of extinction
in ecologically favorable conditions.
( 英 文 ). Novitskaya L I. Paleontological
Journal, 2008, 42(2): 181-191 3 图 版 .
Changes in the taxonomic composition
of Early Devonian amphiaspids represented
in Siberia by two assemblages
(from the northwestern Siberian Platform
and Taimyr) are analyzed. The
study is performed at the generic level
and represented by diagrams. Changes
in the amphiaspid composition are compared
with changes in the development
of the Taimyr and platform paleobasins.
It is shown that shifts in ecological conditions
at the stages of extinction of amphiaspids
occurred within the limits of
changes of abiotic factors (depth, salinity,
etc.) that are usual for heterostracans.
The disappearance (extinction) of amphiaspids
is attributable to the level of
their morphological organization, which
caused inefficient adaptations to the developing
paleoecosystems. The disappearance
(extinction) of groups resulting
from inadequate vital adaptations to the
changing structure of paleoecosystems is
considered to be a general law of evolution.
2010010419
俄 罗 斯 地 台 中 心 区 域 上 弗 拉 斯 阶 厚 甲
鱼 一 新 种 = A new pachyosteomorph
arthrodire (Pisces: Placodermi) from the
Upper Frasnian of the Central Devonian
Field, Russia. ( 英 文 ). Zakharenko G V.
Paleontological Journal, 2007, 41(6):
642-655 7 图 版 .
A new genus and species of pachyosteomorph
arthrodire, Omalosteus
krutoensis gen. et sp. nov. from shallowwater
marine deposits of the Evlanovo
Regional Stage (Upper Frasnian, Upper
Devonian) of the Central Devonian Field
is described. It is tentatively referred to
the family Trematosteidae Gross, 1932,
which was earlier believed to be endemic
to central Europe. The new genus
is characterized by a rounded, dorsoventrally
compressed cross section of the
pectoral region and smooth head shield
and postcranial membrane bones. The
centrale is elongated, forming a narrow
lateral lobe. The praeorbitale, postorbitale,
and centrale come in contact in the
center of the orbital region. The mediodorsale
is wide, its carinal process projects
considerably posteriorly. The anterior
margin of the anterior ventrolaterale
lacks articular facets for the interlaterale.
2010010420
俄 罗 斯 库 尔 斯 克 市 地 区 Mikhailovskii
矿 弗 拉 斯 阶 下 部 的 Psammosteiforms
= Psammosteiforms (Agnatha, Heterostraci)
from the Lower Frasnian of the
Mikhailovskii Mine, Kursk Region,
Russia. ( 英 文 ). Moloshnikov S V. Paleontological
Journal, 2007, 41(5): 558-
563 4 图 版 .
Psammosteiforms, including Tartuosteus
(?) zheleznogorskensis, sp. nov.
and Psammosteus cf. P. praecursor
Obruchev, from the Lower Frasnian
(Upper Devonian) of the Mikhailovskii
Mine (Kursk Region) are described. Agnathans,
placoderms, crossopterygians,
and acanthodians from this locality are
determined. The similarity of the Mikhailovskii
Fish Assemblage to the assemblage
of southern Timan suggests it
be assigned to the Upper Timan Regional
Stage.
2010010421
无 颌 类 属 种 多 样 性 的 演 化 = Evolution
of generic and species diversity in agnathans
(Heterostraci: Orders Cyathaspidiformes,
Pteraspidiformes). ( 英 文 ). Novitskaya
L I. Paleontological Journal,
2007, 41(3): 268-280 4 图 版 .
The evolution of generic and species
diversity in agnathans (orders Cyathas-
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