کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4747919 | 1359947 | 2006 | 5 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Podospermum gen. et sp. nov., an Acmopyle-like dispersed silicified ovule/seed from Lower Cretaceous intertrappean beds of the Rajmahal Basin, India
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
علوم زمین و سیارات
فسیل شناسی
پیش نمایش صفحه اول مقاله

چکیده انگلیسی
An investigation of silicified ovules/seeds recovered from the Early Cretaceous intertrappean rocks of Sonjori, Rajmahal Basin, has revealed the occurrence of Acmopyle-like ovules/seeds described here as Podospermum rajmahalensis gen. et. sp. nov. These fossils depict characteristic features of podocarpaceous ovules/seeds, i.e., erect posture of drupaceous ovule/seed subtended by a fertile bract; ovuliferous scale indistinguishable from the integument enclosing an ovule; integument consisting of three layers and a nucellus free from integument except at base. The presence of two archegonia in the apical part of the female prothallus and the presence of tentpole-like nucellar tissue in the ovule indicate the post-pollination stage of development of the ovule. Moreover, the presence of embryonic tissue in the female prothallus indicates the post-fertilization stage. The presence of these podocarpaceous remains further confirms the palaeoposition of the Indian subcontinent during the Early Cretaceous period.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Cretaceous Research - Volume 27, Issue 5, October 2006, Pages 707-711
Journal: Cretaceous Research - Volume 27, Issue 5, October 2006, Pages 707-711
نویسندگان
Jayasri Banerji, Amit K. Ghosh,