Florigerminis jurassica Cui &amp; Hou &amp; Yin &amp; Wang 2022, gen. et sp. nov
Creators: name: Cui, Da-Fang
name: Hou, Yemao
name: Yin, Pengfei
name: Wang, Xin
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Plantae
Florigerminis
Florigerminis jurassica

description: <i>Florigerminis jurassica</i> gen. et sp. nov. <i>Etymology</i>. <i>jurassica</i> for the Jurassic, the age of the fossil plant (Figs 2 &amp; 3). <i>Species diagnosis</i>. In addition to the generic diagnosis, branch 21 mmlongand 2.6 mm wide, slightly tapering distally, internode 2.9–5.1 mm long. Leaf scars 0.4–0.6 mm wide and 0.23 mm thick. Flower bud pedicel straight, 4.6 mm long and 1 mm wide. Flower bud 3.8 mm long and 3.3 mm wide. Lower tepals 1.2 mmlongand&gt;0.8 mm wide. Uppertepals 1.8–3.8 mmlongand 1.5–2.6 mm wide. Fruit approximately 11.5 mmlongand 7.7 mm wide, on a longitudinally striated 22 mm-long and 0.65 mmwide pedicel, with an apical invagination approximately 0.5 mm deep, and persistent foliar parts approximately 2.4 mmlongand 1.4 mm wide. Endocarp approximately 9 mm long and 6 mm wide. <i>Holotype</i>. PB21737. <i>Description</i>. The holotype specimen is 42 mm long and 20 mm wide, preserved as a compression with some coalified residue and an impression (Fig. 2a). The plant tissues are embedded in yellowish volcanic tuff (Fig. 2a–c). When the coalified residue falls off, an exquisite morphological impression is left on the fine sediment matrix (Figs 2d–i &amp; 3a–g). The preserved part of the fossil includes a leafy branch that is physically connected to a fruit and a flower bud (Fig. 2a). The branch is elongated, approximately 21 mm long and 2.6 mm wide, with longitudinal fine striations on its surface and at least five nodes, tapering distally (Figs 2a, d, h &amp; 3b, d, e). The nodes are marked by several transversal wrinkles (Figs 2h &amp; 3b). The lengths of the internodes increase from 2.9 mm at the proximal to 5.1 mm at the distal (Fig. 2a, h). Leaves with decurrent bases are helically arranged along the branch, more concentrated to the distal portion of each internode (Figs 2h &amp; 3d). All of the leaves have been abscised and only have their scars left on the branch (Figs 2a, h &amp; 3d). The leaf scars are 0.4–0.6 mm wide and 0.23 mm thick, with terminal abscission zones (Fig. 3b, d &amp; e). Close to the terminal of the branch, fruit pedicel scars are subtended by bracts (Fig. 3a– c). The fruit pedicel with longitudinal fine striations is rounded in cross-view, branching into a pair (Figs 2a–c, i, j &amp; 3h–i). The fruits are inserted subapically (Figs 2a, b &amp; 3a). The flower bud (only one visible in full) is in pairs, on a straight pedicel approximately 4.6 mm long and 1 mm wide, oval in shape, approximately 3.8 mm long and 3.3 mm wide (Fig. 2a, b, e– g, i, j). Several layers of upper tepals enwrap the central part (Figs 2e–g, 3g–i, 4 &amp; 5a). Micro-CT sections indicate that the tepals surround the bud centre (gynoecium?) (Fig. 3h, i). Uppertepals vary from 1.8 to 3.8 mm in length and from 1.5 to 2.6 mm in width (Figs 2e–g, 3g &amp; 5a), distinguishing from each other by differently orientated sculpture (Figs 2e–g, 3g, 4 &amp; 5a). The fruit is approximately 11.5 mm long and 7.7 mm wide, on a pedicel 22 mm long and only 0.65 mm wide, subtended by four (only three visible in the fossil) foliar parts approximately 2.4 mmlongand 1.4 mm wide, with an apical invagination approximately 0.5 mm deep (Figs 2a, c, k, l &amp; 3j). Only the mesocarp and endocarp of the fruits are visible, while the exocarp (epidermis) is too thin to see (Figs 2a, c, k &amp; 5b). The mesocarp is approximately 0.34–1.1 mm thick, much thinner near the fruit tip (Figs 2a, c, k &amp; 5b). The endocarp is approximately 9 mm long and 6 mm wide, with a pointed tip (Figs 2a, c &amp; 5b). <i>Depository</i>. The Nanjing Institute of Geologyand Palaeontology, Nanjing, China. <i>Remarks</i>. Only one flower bud and one fruit are preserved in entirety in this fossil. However, there is one extra slender pedicel that is identical to that of the preserved fruit (Fig. 2a, b, i), and there seems to be another pedicel of a flower bud embedded in the sediments (Fig. 2i, j). Considering the morphology of the fruit pedicel, we assume that it is another fruit, which, unfortunately, is not visible in this specimen. Furthermore, several fruit pedicel scars (Fig. 3a–c) strongly imply the existence of fallen fruits in <i>Florigerminis</i>. Therefore, we assume that this fossil originally bore two fruits and two flower buds.
description: Published as part of <i>Cui, Da-Fang, Hou, Yemao, Yin, Pengfei &amp; Wang, Xin, 2022, A Jurassic flower bud from China, pp. 1-13 in Geological Society, London, Special Publications 521</i> on page 4, DOI: 10.1144/SP521-2021-122, http://zenodo.org/record/5883880