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A new species of Sparganium from the Eocene of Fushun, Liaoning Province


 Sparganium fushunense Geng is described as new from the Jijuntun Formation
(Middle to Late Eocene) of Fushun region in Liaoning Province, China. The preserved fer-
tile branches bear fruiting heads. A morphological comparison of the fruit heads is made be-
tween the specimens studied here with those of the living species and other fossil species.
The results show that the new species is distinguishable mainly by the shape of the tepals and
the size of the fruits.
      Sparganium fushunense Geng, sp. nov.
      Head-bearing axis at least 14.5 cm long, about 1.0 mm wide, with longitudinal striae
more or less parallel on its surface. Axes with 4~6 lateral fruit heads, interval between
heads 0.5~2.0 cm. Fruiting head sessile, globose, about 5 mm in diameter, made up of
tightly packed tepals and fruits radiating from a small receptacle. Tepals narrowly obovate,
apically rounded, about 1.8 mm long, 0.2~0.7 mm wide. Fruits elliptic, sessile, with
smooth surface, 1.16~1.25 mm long, at apex with a beak 1.5~2.0 mm long. Seed ellip-
tic, long axis 0.48~0.75 mm long, short axis 0.23~0.45 mm long. Seed coat cells irregu-
larly polygonal , 4.1~19 vn in diameter, with smaller ones in both the apical and basal
parts,the larger ones in the middle part and a papillate process at the apex.


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