Alasemenia, the earliest ovule with three wings and without cupule
- Key Laboratory of Orogenic Belts and Crustal Evolution, Department of Geology, Peking University, China
- School of Geoscience and Surveying Engineering, China University of Mining and Technology, China
- School of Life Sciences, Sun Yat-Sen University, China
- College of Life Sciences, Linyi University, China
- Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, China
Figures
Figure 1
Fertile branches and seeds of Alasemenia tria gen. et sp. nov.
(a) Thrice dichotomous branch with a terminal ovule. Arrow indicating boundary between ovule and ultimate axis (PKUB21721a). (b, f, g, i) Once dichotomous branch with a terminal ovule (PKUB21781, PKUB23132, PKUB19338a, PKUB17899). (c) Twice dichotomous branch with a terminal ovule (PKUB19713a). (d, e) Ovule with three integumentary wings (PKUB19321, PKUB19316). (h) Ovule showing two integumentary wings (PKUB19282). (j, k) Ovule terminating short ultimate axis (PKUB23114, PKUB23129). Scale bars, 1 cm (a–c, h), 5 mm (d–g, i–k).
Figure 2
Fertile branches and seeds of Alasemenia tria gen. et sp. nov.
(a–c) Once dichotomous branch with a terminal ovule (PKUB16876a, b, PKUB17767). a, b, Part and counterpart. (d, e) Part and counterpart, arrow showing the third integumentary wing (PKUB19322a, b). (f) Ovule on ultimate axis (PKUB21752). (g, h, k–m) Ovules lacking ultimate axis (PKUB16788, PKUB21631, PKUB16522, PKUB21647, PKUB21656). (i, j) Part and counterpart, showing limit (arrows) between nucellus and integument (PKUB19339a, b). (n) Four detached ovules (arrows 1–4) (PKUB19331). (o) Enlarged ovule in n (arrow 2), showing three integumentary wings (arrows). Scale bars, 1 cm (n), 5 mm (a–h, k–m, o), 2 mm (i, j).
Figure 3
Seeds of Alasemenia tria gen. et sp. nov.
(a, b) Part and counterpart, enlarged ovule in Figure 1a (PKUB21721a, b). (c) Enlarged ovule in Figure 1c. (d) Counterpart of ovule in c (PKUB19713b). (e) Dégagement of ovule in d, exposing the base of the third integumentary wing (arrow). (f) Enlarged ovule in Figure 1d. (g, h) Enlarged ovule in Figure 2i and j, respectively. Scale bars, 5 mm (a–e), 2 mm (f–h).
Figure 4 with 5 supplements
Transverse sections of seeds of Alasemenia tria gen. et sp. nov.
(a, b) Part and counterpart. (c–e) Sections of seed in a and b (at three lines, in ascending orders). Arrow in d indicating probable nucellar tip (Slide PKUBC17913-12b, 10a, 9b). (f, g) Part and counterpart. (h–k) Sections of seed in f and g (at four lines, in ascending orders) (Slide PKUBC19798-8b, 6b, 4a, 4b). (l, m) Part and counterpart. (n–r) Sections of seed in l and m (at five lines, in ascending orders), showing three wings departing centrifugally (Slide PKUBC17835-5a, 7b, 8b, 9a, 10a). (s, v, A), One seed sectioned. (t, u) Sections of seed in s (at two lines, in ascending orders) (Slide PKUBC18716-8b, 7a). (w–z) Sections of seed in v (at four lines, in ascending orders) (Slide PKUBC20774-7a, 6b, 3a, 3b). (B–E) Sections of seed in A (at four lines, in ascending orders), showing three wings departing centrifugally (Slide PKUB17904-5b, 4a, 4b, 3b). Scale bars, 2 mm (a, b, f, g, l, m, s, v, A), 1 mm (c–e, h–k, n–r, t, u, w–z, B–E).
Figure 4—figure supplement 1
Transverse sections of two seeds of Alasemenia tria gen. et sp. nov.
(a–k) Serial sections of seed in Figure 4a and b, at 11 levels and in ascending order (Slide PKUBC17913-13b, 12a, 12b, 11a, 11b, 10a, 10b, 9a, 9b, 8a, 8b). (j, k) Arrows indicating integumentary lobes. (l-x) Serial sections of seed in Figure 4f and g, at 13 levels and in ascending order (Slide PKUBC19798-11a, 9a, 9b, 8a, 8b, 7a, 7b, 6, 6b, 5a, 5b, 4a, 4b). (c, f, i, p, t, w, x) The same as those in Figure 4c–e and h–k, respectively. Scale bars, 1 mm.
Figure 4—figure supplement 2
Transverse sections of one seed of Alasemenia tria gen. et sp. nov.
(a–q) Serial sections of seed in Figure 4l and m, at 17 levels and in ascending order (Slide PKUBC17835-4b, 4a, 5b, 5a, 6b, 6a, 7b, 7a, 8b, 8a, 9b, 9a, 10b, 10a, 11b, 12a, 12b). (d, g, i, l, n) The same as those in Figure 4n–r, respectively. (m–q) Arrows indicating integumentary lobes. Scale bars, 1 mm.
Figure 4—figure supplement 3
Transverse sections of two seeds of Alasemenia tria gen. et sp. nov.
(a–d) Sections of seed in Figure 4s, at 4 levels and in ascending order (Slide PKUBC18716-10a, 8a, 8b, 7a). (e–i) Sections of another seed (at 5 levels, in ascending order) (Slide PKUBC18984-9b, 8b, 8a, 7b, 7a). (c, d) The same as those in Figure 4t and u, respectively. Scale bars, 1 mm.
Figure 4—figure supplement 4
Transverse sections of one seed of Alasemenia tria gen. et sp. nov.
(a–l) Serial sections of seed in Figure 4v, at 12 levels and in ascending order (Slide PKUBC20774-9a, 9b, 8a, 8b, 7a, 7b, 6a, 6b, 5a, 5b, 3a, 3b). (e, h, k, l) The same as those in Figure 4w–z, respectively. Scale bars, 1 mm.
Figure 4—figure supplement 5
Transverse sections of one seed of Alasemenia tria gen. et sp. nov.
(a–j) Serial sections of seed in Figure 4A, at 10 levels and in ascending order (Slide PKUBC17904-6a, 6b, 5a, 5b, 4a, 4b, 3a, 3b, 2a, 2b). (d-f, h) The same as those in Figure 4B–E, respectively. Scale bars, 1 mm.
Figure 5
Reconstruction of two acupulate ovules with integumentary wings.
(a) Alasemenia tria with three wings distally extending outwards. (b), A. tria with one of three wings partly removed to show nucellar tip. (c) Guazia dongzhiensis with four wings distally extending inwards (Wang et al., 2022). Scale bars, 5 mm.
Figure 6
The mathematical analysis of wind dispersal ability of ovules with 1–4 wings.
The maximum windward area of each wing is and represents the number of wings per ovule. is the distance from the tip of wing to the axis of ovules. represents the area of windward when the angle between airflow and wings is , and represents the accumulated area of windward in a cycle. means relative efficiency for wind dispersal. Red lines and expressions show the situation of .
Additional files
Download links
A two-part list of links to download the article, or parts of the article, in various formats.
Downloads (link to download the article as PDF)
Open citations (links to open the citations from this article in various online reference manager services)
Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)
Alasemenia, the earliest ovule with three wings and without cupule
eLife 13:RP92962.
https://doi.org/10.7554/eLife.92962.3
