Cheirolepidiaceae

From Palaeos

The Cheirolepidiaceae were a family of conifers, superficially similar to Cupressaceae, that were a significant part of the Mesozoic flora (Axsmith et al., 2004). They are united by the possession of a distinctive pollen type assigned to the form genus Classopollis. The name Frenelopsidaceae (as a separate family) or "frenelopsids" has been used for a group of Cheirolepidiaceae with jointed stems, think internode cuticles, sheathing leaf bases and reduced free leaf tips.

Note that while Pseudofrenelopsis has been listed below as a synonym of Classostrobus in order to reflect an established association between these taxa, this is not technically correct. Both are "organ genera", the former referring to the shoots, the latter to the pollen cones. Because organ genera only refer to specific parts of the plant, they cannot usually be officially synonymised. The use of organ genera has developed in palaeobotany because plant fossils are most often found with the different parts separated from each other. Not only is it not always possible to confidently establish which cone goes with which shoot, but different species may not differ in every part – for instance, different shoots assignable to Pseudofrenelopsis parceramosa have been found bearing cones assignable to both Classostrobus comptonensis and C. arkansensis (Axsmith et al.]], 2004)

<==Cheirolepidiaceae [Frenelopsidaceae]
   |--Alvinia bohemica
   |--Classostrobus Alvin, Spicer & Watson 1978 [incl. Pseudofrenelopsis, Suturovagina]
   |    |--*C. comptonensis Alvin, Spicer & Watson 1994 (see below for synonymy)
   |    |--C. arkansensis Axsmith, Krings & Waselkov 2004
   |    |--C. cathayanus [incl. Pseudofrenelopsis intermedia]
   |    |--C. turolensis Gomez, Martín-Closas et al. 2002
   |    `--C. ugnaensis Gomez, Martín-Closas et al. 2002
   |--Cupressinocladus Seward 1919 [incl. Watsoniocladus]
   |    |--C. asferensis Barale & Ouaja 2002
   |    |--C. itieri (Saporta) Barale 1981
   |    |--C. leptocladoides (Berry) Pons 1990
   |    |--C. micromerum (Heer) Pais 1974
   |    |--C. pompeckji (Salfeld) Pons 1990
   |    |--C. pseudoexpansum Barnard & Miller 1976
   |    `--C. soltanensis Barale, Ouaja & Philippe 2000
   `--Frenelopsis Schenck 1869
        |--*F. hoheneggeri (Ettingshausen) Schenck 1869 (see below for synonymy)
        |--F. alata Feistmantel 1881
        |--F. choshiensis
        |--F. elegans
        |--F. harrisii Doludenko & Reymanówna 1978
        |--F. kaneviensis Barale & Doludenko 1985
        |--F. occidentalis
        |--F. oligostomata
        |--F. pombetsuensis
        |--F. ramosissima
        |--F. rubiesensis Barale 1973
        |--F. sifloana Watson 1983
        |--F. teixeirae
        |--F. turolensis Gomez, Martín-Closas et al. 2002
        |--F. ugnaensis Gomez, Martín-Closas et al. 2002
        `--F. veneta Gomez, Thévenard et al. 2002

*Classostrobus comptonensis Alvin, Spicer & Watson 1994 [incl. Pseudofrenelopsis parceramosa (Fontaine) Watson 1977 (mt)] *Frenelopsis hoheneggeri (Ettingshausen) Schenck 1869 [=Thuites hoheneggeri Ettinghausen 1852]

* Type species of genus indicated

References

Axsmith, B. J., M. Krings & K. Waselkov. 2004. Conifer pollen cones from the Cretaceous of Arkansas: Implications for diversity and reproduction in the Cheirolepidiaceae. Journal of Paleontology 78: 402-409.

Barale, G., & M. Ouaja. 2002. La biodiversité végétale des gisements d’âge Jurassique supérieur-Crétacé inférieur de Merbah El Asfer (Sud-Tunisien). Cretaceous Research 23: 707-737.

Gomez, B., C. Martín-Closas, G. Barale, N. Solé de Porta, F. Thévenard & G. Guignard. 2002. Frenelopsis (Coniferales: Cheirolepidiaceae) and related male organ genera from the Lower Cretaceous of Spain. Palaeontology 45 (5): 997-1036.

Gomez, B., F. Thévenard, M. Fantin & L. Guisberti. 2002. Late Cretaceous plants from the Bonarelli Level of the Venetian Alps, northeastern Italy. Cretaceous Research 23: 671-685.

Credits

CKT070201