Chara zeylanica Klein ex Willd., Mém. Acad. Roy.

Casanova, Michelle T. & Karol, Kenneth G., 2023, Charophytes of Australia’s Northern Territory - I. Tribe Chareae, Australian Systematic Botany 36 (1), pp. 38-79 : 75

Chara zeylanica Klein ex Willd., Mém. Acad. Roy. Sci. Hist. (Berlin) 1803: 86 (1805)

Chara polyphylla subsp. ceylanica A.Braun, Boston J. Nat. Hist. 5: 264 (1845), nom. illeg.; C. gymnopus var. ceylanica (A.Braun) Allen, Charac. America 1: 63 (1888), as ʻ Ceylonica ʼ. Type: Ceylon collecta, 26 May 1798, J.Klein 508 (lecto: B-W!; isolecto: HBG!, MEL!).

Chara zeylanica f. typica Zaneveld , Blumea 4: 208 (1940), nom. inval.

Monoecious. Plants up to 10–50 cm high, compact and often highly calcified in shallow water, but elongate in deeper water ( Fig. 22 a ). Axes up to 400–800 µm in diameter; internodes essentially 3× corticated, (22–30 cells around), 24–65 mm long ( Fig. 22 b ). Spine cells sometimes obscure, where present occurring singly, in pseudo-whorls on the axes, very long and thin up to 800–1000 μm long and 20–40 μm wide ( Fig. 22 b ). Stipulodes in 2 whorls, uppers pointing up (500–600 μm long), lowers pointing down (300–400 μm long), 2× the number as branchlets in each of the whorls ( Fig. 22 c ). Branchlets 9–11 in a whorl, 10–22 mm long, segments 6–8, the basal cell ( Fig. 22 d ) and 1 or2 end cells not corticated (sometimes the basal cell is obscured by the upper row of stipulodes), the remainder corticated with ~14–18 cells around ( Fig. 22 c ). Bract cells 4–6 verticillate at the branchlet nodes, elongate, inner cells up to 0.4–1.2 mm long, outer up to 0.6 mm long, bracteoles 2, up to 0.5–1.3 mm long ( Fig. 22 e ). Gametangia conjoined singly at the lowest 4 or 5 branchlet nodes. Oosporangia 1000–1200 µm long and 600–700 µm wide, 9 stripes of helical cells, coronula up to 100–150 µm high, cells appressed. Oospores black, 850 µm long, 250 µm wide ( Fig. 22 f ), fossa wall with a calcified covering (gyrogonite 1000 µm long). Striae of 10 or 11 flanged ridges, fossa wall 80 μm across, papillate ( Fig. 22 g ), small basal claws present. Basal cell impression rounded, ~100 µm in diameter ( Fig. 22 h ) Antheridia 200–250 µm in diameter, tetrascutate ( Fig. 22 e ). Chromosomes n = 28 (specimen A. T.Hotchkiss, 5 Nov. 1968 ( B)).

Distribution

In freshwater streams and rivers in the north of Australia, throughout tropical Asia and most of the tropical regions of the world.

Etymology

Zeylanica is from the Latin Zeylonas, the species being named for its occurrence in Ceylon ( Sri Lanka).

Notes

Plants are usually notably coarse and smelly, with abundant reproductive structures visible along the branchlets. Chara zeylanica is one of a few Chara species known with tetrascuate antheridia (with 4 lozenge-shaped shield cells, rather than the 8 triangular shield-cells typical of the genus; Proctor et al. 1971). Sterile plants are distinguished on the basis of the naked (ecorticate) basal branchlet cell, the well-developed stipulodes in two rows, and the axial cortex cells three times the number of branchlets in the adjacent whorl, often with long spine cells. A single specimen from Pullout Bore ( P. K.Latz & A.Schubert 28441 (DNA)) has variable development of the axial cortex, similar to Chara brittonii Allen ex C.B.Rob. , but is retained in C. zeylanica pending further study.

Specimens examined

NORTHERN TERRITORY: Pullout Bore , 15 km NNW of Amanbidji Settlement, 11 Sep. 2013, P. K. Latz & A . Schubert 28441 (DNA) [specimen without axial cortex in part]; Upper Wickham River, 1 Mar. 1989, Russell-Smith 7734 & Lucas (DNA); Gove Road at Mainoru River Crossing , 21 Oct. 1981, T. S. Henshall 3895 (DNA); Bradshaw Station , 18 Feb. 1999, C. R. Michell 2157 (DNA); Jarong Spring, Wingate Mountains 16 Mar. 1989, Brock 701 & Russell-Smith (DNA); Daly River Mission , 6 Oct. 1992, L. L. V. Williams 296 & G. M . Wightman (DNA); Lake Eames, Vanderlin Island , 1 Aug. 1988, P. K. Latz 11084 ( BRI, DNA, MEL, NT); Roper River , 2000, S. Townsend R4 (DNA) ; waterfall pool north of West Baines River Crossing , 5 Nov. 1968, A. T. Hotchkiss x-251 ( B); Daly River , 2001, S. Townsend p56 ( MEL); Howard Springs , Darwin area, 28 June 1977, L. A. Craven 4472 ( CANB); Bulls Run Creek, Tipperary Station , 4 May 1990, G. J. Leach & I . D. Cowie 2852 (DNA, MEL); Mataranka Reserve, 4 May 1977, Must 1487 ( CANB, MEL); Daly River crossing, 12 Nov. 1982, C. R. Dunlop 6293 (DNA); Amelia Springs , MacArthur River area, 30 Jan. 1976, L. A. Craven 3536 (DNA); Robinson River , approx. 12 km N of Seven Emu, 10 May 1985, G. Leach 631 (DNA, MEL, NT); Kulamindini Swamp, near Elliott , 22 Apr. 1991, D. J. Parsons 137 (DNA); Chambers Bay, Woolner Station , coastal floodplain, 19 June 1995, I. Cowie & R . Griffin 5851 (DNA); Port Darwin , 9 Apr. 1896, T. B. Blow A98 ( BM) .

Figures

Fig. 22. Chara zeylanica, (a–e) from A.T.Hotchkiss X-251, (b, f–g) from the isotype specimen J.Klein 508 (HBG), (h) from S.Townsend p56 Daly RIver (MEL). (a) Habit of whole plant, scale bar: 5 cm. (b) Axis with 3× cortex and spine cells, scale bar: 0.5 mm. (c) Fertile branchlets, scale bar: 1 cm. (d) Base of branchlet whorl with uncorticated basal branchlet cells (upper row of stipulodes removed), scale bar: 1 mm. (e) Gametangia with oosporangium, tetrascutate antheridium, bracteoles and bract cells on a corticated branchlet, scale bar: 500 µm. (f) Scanning electron micrograph (SEM) of oospore, scale bar: 200 µm. (g) SEM of detail of oospore wall, scale bar: 20 µm. (h) SEM of impression of end cell on oospore wall, scale bar: 100 µm.