Chapter 1: The Characeae Plant

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18 entities within the complex has not been fully examined. We can be sure, at least, that dioecious specimens that originated in eastern Australia and have the morphology illustrated in Fig. 1.5, can be called Chara australis, and that monoecious specimens that have a similar morphology are likely to be Chara corallina. 1.4.2.2 Lamprothamnium inflatum (Fil. & G.O. Allen ex Fil.) A. García & K.G. Karol This curious species (Fig. 1.8) has been well known, and misnamed for a long time. The first collection of this species was made by Nancy Burbidge, the eminent Australian taxonomist, in 1933, while swimming in Lake Parkeyerring near Wagin in Western Australia. It is an attractive plant when actively growing, looking like small bunches of glistening green grapes. The preserved specimens were sent to G.O. Allen (in England) who was the world expert on charophytes in the English-speaking world at the time. He sent a subsample to F. Filarszky in Hungary, who described the species as Nitellopsis inflata. In recognition of the role that Allen had in the discovery, Filarszky included Allen in the authorship of the species, although Allen was not consulted about the determination (Wood 1964). Next, this odd species was included in the genus Protochara by South Australian phycologists Womersley and Ophel (1940) although they had not examined any specimens (Womersley and Ophel 1940). When Macdonald and Hotchkiss (1956) investigated the genus Protochara (specifically Protochara australis) their results indicated that the genus should be amalgamated with Chara, so Protochara inflata became Chara inflata (Fil. & G. O. Allen ex Fil) Macdon. & Hotch., again, without a thorough examination of any specimens of the species. Then, in a revision of the Australian charophyte flora Wood (1962, 1965, 1972) reduced the species to a form of Chara corallina (C. corallina var. nobilis f. inflata) despite the fact that it was monoecious and all other Australian specimens in that group were dioecious. Thus the species was allocated to three different genera. However, recent evidence places the species firmly within the genus Lamprothamnium (García and Karol 2004). This placement is supported by morphological characteristics such as the presence of gyrogonites (calcium carbonate ‘shells’ around the oospore), contracted apical whorls and occasional downward-pointing stipulodes (Fig. 1.8). 1.4.2.3 Chara longifolia C.B. Robinson This enigmatic species has been described as three different species, in two genera in the past: Chara longifolia (which is the currently accepted name), C. buckellii and Nitellopsis
19 bulbilifera. The natural range of the species is in North, South and Central America in brackish habitats (Mann et al. 1999). Chara longifolia was originally collected from Kansas, USA by M.A. Carleton in 1891 (Robinson 1906). The species was dioecious, had an irregularly corticated axis, poor development of stipulodes (absent in older nodes) with c. 8 ecorticate branchlets in each whorl with distinctive decumbent bract cells. Robinson commented on the similarity of this species with Nitellopsis, but described it as a new species of Chara (Robinson 1906). The species was known only from its type collection (Wood 1965). In 1928 Dr Edward Buckell, a friend of the British charophyte specialist James Groves, collected another specimen from British Colombia, Canada which was described by Allen (1951) as Chara buckellii. Again, the specimens had irregularly or incompletely corticated axes, with ecorticate branchlets and posterior bract cells distinctively deflected downwards. Again, this species was known only from the type locality (Allen 1951; Wood 1965). In 1959 a specimen was cultured from soil collected from Laguna La Brava near Buenos Aires, Argentina, by Carlotta Carl de Donterberg, who described it as Nitellopsis bulbilifera (Carl de Donterberg 1960). Tindall et al. (1965) reported N. bulbilifera (cited as N. bulbillifera) from New Mexico, and illustrated the morphology of the thallus. Although Tindall et al. (1965) received Chara buckellii from V.W. Proctor in Texas for examination at the time of their study of N. bulbilifera, they concluded that despite the common characteristics with C. buckellii (dioecious nature, and similarity of morphology of the branchlets and bract cells), the presence of a corticated stem and stipulodes in C. buckellii was sufficient to distinguish the two taxa. Daily (1967) also examined the taxon, and transferred all the previously described species to the genus Lamprothamnium, but this taxonomic change was very short-lived, as in the next article in the same issue of J. Phycol. Proctor et al. (1967) presented evidence that all of the species (Chara longifolia, C. buckellii and N. bulbilifera) were conspecific. The evidence consisted of 1) similar morphology, 2) the same number of chromosomes, and 3) the production of viable oospores when crossed. This finding, and the designation to the genus Chara, has been further supported by genetic studies (Meiers et al. 1999). Since all these taxa are the same species of Chara, the oldest name has priority, thus the species is Chara longifolia C. B. Robinson. 1.4.3 Lessons to be learned The morphology of ecorticate charophytes is relatively simple, and there are few outstanding characters with which to distinguish species. Those that are available (arrangement and angles of stipulodes and bract cells, arrangement of gametangia) are not always obvious or
Page 1 and 2: 1 Chapter 1: The Characeae Plant 1
Page 3 and 4: 3 1.1 General Morphology The chara
Page 5 and 6: 5 largest cells, and for this reas
Page 7 and 8: 7 Lamprothamnium in 1916 to avoid
Page 9 and 10: 9 of inflated branchlets develop,
Page 11 and 12: 11 where the antheridia are termin
Page 13 and 14: 13 zygote and the maternal spiral
Page 15 and 16: 15 1.4.1 Systematics and the conce
Page 17: 17 definition of species (Proctor
Page 21 and 22: 21 do they occur?’ are central t
Page 23 and 24: 23 of animal and algal epiphytes (
Page 25 and 26: 25 1.5.4.4 Temperature Storage tem
Page 27 and 28: 27 annuals (i.e. reproducing once
Page 29 and 30: 29 growth has taken place (e.g. Ch
Page 31 and 32: 31 Figure 1.15 The characeae oospo
Page 33 and 34: 33 antheridia clustered at the bas
Page 35 and 36: 35 Casanova, M.T. and Karol, K.G.
Page 37 and 38: 37 Proctor, V.W. 1960. Dormancy an

Chapter 1: The Characeae Plant

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