کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
4750135 1642482 2015 11 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Morphology and wall ultrastructure of a new and highly distinctive megaspore from the Middle Jurassic of Yorkshire, UK
ترجمه فارسی عنوان
مورفولوژی و زیر ساخت های دیوار یک مگاسپور جدید و بسیار متمایز از ژوراسیک میانی یورکشایر، انگلستان
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات فسیل شناسی
چکیده انگلیسی


• We describe a new megaspore form the Middle Jurassic deposits of Yorkshire, England.
• The megaspore has novel and highly distinctive ornament.
• Evidence from morphology and wall ultrastructure suggest that the megaspore is most likely lycopsid.

We describe a new and rather unusual megaspore recovered from Middle Jurassic terrestrial deposits of Yorkshire, England that we name Reticuspinosporites whytei gen. et sp. nov. The contact area is non-trilete and is formed where an outer sculptured layer has not developed. This outer layer covers the remainder of the megaspore and bears novel sculpture consisting of a highly irregular reticulum with areas ‘infilled’ to form plateaus that bear long spines. Analysis of wall ultrastructure reveals a four-layered wall comprising from inside to outside: (i) innermost, separated lamina; (ii) inner homogeneous layer; (iii) central spongy layer; and (iv) outermost homogeneous layer that forms the sculpture. Wall ultrastructure is not entirely diagnostic but is most suggestive of lycopsid affinities. Unusually the megaspores commonly occur in pairs. They are not attached at their contact faces but by their equatorial or distal surfaces through entanglement of their spines. We interpret this feature as possibly an adaptation for floating and transport by water.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Review of Palaeobotany and Palynology - Volume 216, May 2015, Pages 33–43
نویسندگان
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