Fig 2 - uploaded by George Poinar
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Phantophlebia dicycla. Flower in basal view. A. Tepals of the inner perianth whorl. B. Tepals of the outer perianth whorl. C. Broken off tip of pedicel. Scale bar = 1.0 mm.
Source publication
A fossil flower in mid-Cretaceous amber from Myanmar (Burma) is described as the new genus and species Phantophlebia dicycla. The perianth of the flower is composed of two 5-merous whorls of tepals, the outer tepals being smaller and more irregular in shape than the inner. All the tepals are distinctly vascularized, with few to many major veins tha...
Contexts in source publication
Context 1
... probably staminate, perianth glabrous, tepals in two whorls of 5 each, those of the outer whorl small, quincuncial, unequal, narrowly to broadly elliptic, oblanceolate, or obovate, obtuse, with 3-7 main veins interconnected by a network of veinlets ( Fig. 2), tepals of the inner whorl larger and up to 3 times longer than the outer tepals, explanate, ± equal, connate basally, broadly ovate, acute or acuminate, with ca. 7-9 main veins that branch above and are similarly interconnected (Figs. 1, 3), stamens 5, inserted opposite the inner tepals on their connate basal portion, filaments ...
Context 2
... anther attachment basal, anthers angular-oblong, bilocular, dehiscence latrorse by oblique slits, epidermis papillate, connective not prolonged (Figs. 4, 5), anthers absent from 3 filaments, perhaps due to insect predation (note insect trapped under the air bubble [ Fig. 4]), gynoecium probably 0, pedicel 0 or detached below outer tepals (Fig. 2), pollen unknown. Flower diameter 4.7 mm as measured between tips of longest inner tepals, outer tepals 0.6-0.8 mm long, 0.4-0.6 mm wide, inner tepals 1.6-1.9 mm long, 1.1-1.4 mm wide, filaments 0.3 mm long, anthers 0.3-0.4 mm long, 0.1-0.2 mm ...
Context 3
... are often sessile or have short filaments, but in some genera the filaments are longer than the anthers (Ståhl & Anderberg 2004, fig. 91). Anther dehiscence is introrse by longitudinal slits, but in the genus Monoporus of Madagascar, the locules are oblique, connivent at the tip, and open at the apex by one or 2 slit-like pores ( Mez 1911, fig. 27F; Ståhl & Anderberg 2004, p. 280). In the anthers of Phantophlebia (Figs. 4, 5), the oblique slits approach each other at the tip but are not connivent. Anthers in Myrsinoideae are most often sagittate and dorsifixed but are rarely ovate or elliptic and basifixed (Mez 1911, p. 1) as in ...
Context 4
... probably staminate, perianth glabrous, tepals in two whorls of 5 each, those of the outer whorl small, quincuncial, unequal, narrowly to broadly elliptic, oblanceolate, or obovate, obtuse, with 3-7 main veins interconnected by a network of veinlets ( Fig. 2), tepals of the inner whorl larger and up to 3 times longer than the outer tepals, explanate, ± equal, connate basally, broadly ovate, acute or acuminate, with ca. 7-9 main veins that branch above and are similarly interconnected (Figs. 1, 3), stamens 5, inserted opposite the inner tepals on their connate basal portion, filaments ...
Context 5
... anther attachment basal, anthers angular-oblong, bilocular, dehiscence latrorse by oblique slits, epidermis papillate, connective not prolonged (Figs. 4, 5), anthers absent from 3 filaments, perhaps due to insect predation (note insect trapped under the air bubble [ Fig. 4]), gynoecium probably 0, pedicel 0 or detached below outer tepals (Fig. 2), pollen unknown. Flower diameter 4.7 mm as measured between tips of longest inner tepals, outer tepals 0.6-0.8 mm long, 0.4-0.6 mm wide, inner tepals 1.6-1.9 mm long, 1.1-1.4 mm wide, filaments 0.3 mm long, anthers 0.3-0.4 mm long, 0.1-0.2 mm ...
Context 6
... are often sessile or have short filaments, but in some genera the filaments are longer than the anthers (Ståhl & Anderberg 2004, fig. 91). Anther dehiscence is introrse by longitudinal slits, but in the genus Monoporus of Madagascar, the locules are oblique, connivent at the tip, and open at the apex by one or 2 slit-like pores ( Mez 1911, fig. 27F; Ståhl & Anderberg 2004, p. 280). In the anthers of Phantophlebia (Figs. 4, 5), the oblique slits approach each other at the tip but are not connivent. Anthers in Myrsinoideae are most often sagittate and dorsifixed but are rarely ovate or elliptic and basifixed (Mez 1911, p. 1) as in ...
Citations
... The fossil flower described here as Cyathitepala papillosa is a further addition to the some 19 new genera of angiosperms previously described from Myanmar amber (details in Liu et al. 2018;Poinar 2018;Poinar & Chambers 2020b). The floral morphology of this selection of mid-Cretaceous fossil taxa is quite diverse, including both spiral and whorled perianths, petaliferous and apetalous forms, bisexual and unisexual flowers, few to many stamens, anthers with longitudinal, valvate, or hippocrepiform dehiscence, pistils with inferior, half-inferior, or superior ovaries, arcuate or erect styles, terminal or decurrent stigmas, and mono-, di-, or tricolpate (porate) pollen. ...
Although partially damaged prior to its preservation in coniferous resin, the flower of Cyathitepala papillosa retains enough morphological features to justify its description as a new genus and species of fossil angiosperms. The perianth is incomplete, but there are at least 6 large outer tepals and numerous smaller, spirally arranged inner ones. The limbs of some of the larger tepals are cup-shaped and face abaxially, while the smaller inner tepals are flat or have adaxially folded margins. There is an inner series of erect, apically truncate tepals surrounding the stamens. The surfaces and margins of the tepals are densely papillate. There is a whorl of ca. 12 stamens with anthers that dehisce by two dorsally hinged valves. Nothing remains of the receptacle or pedicel of the flower, but the superior portion of the pistil is conic and bears two columnar, erect styles. The fossil is compared with three previously described fossil genera, Setitheca, Zygadelphus, and Strombothelya, which were suggested as having a possible relationship with certain families of order Laurales.
The 31 species of flowers that have been recovered from Burmese amber shows the amazing variety of angiosperms that were present in this mid-Cretaceous forest that flourished during the reign of the dinosaurs. Based on their floral diversity, it is obvious that this was a period of experimentation with only a few angiosperm lineages, such as the grasses and laurels, carried through to the present. In amber from this deposit, you can find one flower with multiple sized sepals and other flower with secondary anthers developing from the backs of primary anthers. Angiosperms were also “experimenting” with different ways to attract pollinators and deter herbivores as part of their adaptation to various habitats. Some of these fossil flowers were instrumental in establishing the theory that the flora and fauna of Burmese amber was formed in Gondwana and later rafted to its present location in northern Myanmar.
This is a supplement to the Burmese (Myanmar) amber checklist and bibliography covering taxa described or recorded during 2020, plus a few earlier records that were missed previously. Up to the end of 2020, 1,859 species were recorded from Kachin amber of which 362 were named in 2020, which is the highest number of species named from any kind of amber in one year. Two species were also named from older Hkamti amber.
A flower preserved in 100 Ma amber from Myanmar is described here as Chainandra zeugostylus, a new genus and species of fossil angiosperms. The anthers in Chainandra are sagittate at the base and have only a short connective. They dehisce by means of a circumferential stomium, the dorsal and ventral sides of each locule forming flaps that become widely separated. The style of Chainandra is columnar and two-branched above the middle, and the fully inferior ovary bears an epigynous nectar disc but lacks well-defined ribs or veins. In Tropidogyne, Lacknociona, and Strombothelya, similar genera described earlier from the same am-ber deposits, the styles are either unbranched or are 3–5-branched to near the base, and the ovary is half-inferior to inferior, its lower portion often being dis-tinctly veined and ribbed. Morphology of the stamens and gynoecium of the three genera suggests that they are early members of the eudotyledons.
The flower described here as Valviloculus pleristaminis, a new genus and species of fossil angiosperms, was obtained from Myanmar amber deposits dating to the mid-Cretaceous period. The flower is staminate, with an ovoid, hollow floral cup. The perianth consists of 6 tepals, one of which was lost prior to preservation. Numerous helically arranged stamens are borne at the summit of the flower. The anthers are bilocular, with pollen sacs that dehisce by laterally hinged valves. The tip of the connective bears a cup-shaped appendage. The gynoe-cium is represented only by a cluster of vestigial styles centered among the stamens. The fossil is provisionally assigned to order Laurales, its closest affinities being with the families Monimiaceae and Atherospermataceae.
The fossil flower described here as Thymolepis toxandra is from amber deposits in Myanmar which have been dated as ca. 100 Ma. The peri-anth consists of 12 tepals of varying size and shape, arranged in decussate pairs at the summit of an obconic floral cup. The epidermis of some of the tepals is densely papillate-secretory. The flower is bisexual, the androecium consisting of 2 stamens whose anthers are bisporangiate, hippocrepiform, and densely hirsute. The gynoecium is visible only as a bilobed stigma or as the tips of two postgenitally fused styles, the re-mainder of the pistil(s) being hidden by the perianth and floral cup. It is suggested that the fossil may be an early representative of family Monimiaceae.
