Chara karolii Casanova, Austral. Syst. Bot.
Creators: name: Casanova, Michelle T.
name: Karol, Kenneth G.
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Plantae
Charophyta
Charophyceae
Charales
Characeae
Chara
Chara karolii

description: Chara karolii Casanova, Austral. Syst. Bot. 27: 409 (2014)   
 Type: VICTORIA: temporary wetland on ‘ Lurnea’, Casanova Road, Westmere, 18 Nov. 2008, M. T. Casanova r167 (holo: MEL!; iso: B!, NY!).   
 Chara aff. muelleri ‘Karol’: M. T.Casanova & I. J.Powling. Algae collected for the Lake Condah, Budj Bim Indigenous Protected Area Bush Blitz: 11 [Charophyte Services, Lake Bolac (2011)].   
 Monoecious. Plants robust, up to 60 mm high, without calcium carbonate deposition (Fig. 13 a). Axes up to 400 µm in diameter, 3-corticate in the upper internodes, isostichous, 24–27 cells around (Fig. 13), ecorticate on the lower internodes; spine cells absent or rudimentary. Stipulodes in 1 whorl, alternate, the same number as the number of branchlets, up to 300 µm long (Fig. 13 b). Branchlets 8 or 9 in a whorl, up to 20 mm long, segments 3 or 4, ecorticate (Fig. 13 b), terminated by a corona of ~3 cells (Fig. 13 e). Bract cells 2 or 3 at branchlet nodes, bracteoles 2, as long as the oosporangia (Fig. 13 d). Gametangia conjoined, geminate or clustered at the lowest 2 branchlet nodes (Fig. 13 f), as well as basal oosporangia. Oosporangia 500–600 µm long (including coronula), 250–300 µm wide, 8 or 9 stripes of helical cells, coronula up to 150 µm high. Oospores black 480–660 µm long, 280–400 µm wide, 7 or 8 striae of low ridges (Fig. 13 g), basal-cell impression 85–103 µm in diameter (Fig. 13 j) (25–30% of the diameter of the oospore), oospore wall with a reticulate pattern, when well developed, the reticulum is constructed of small papillae on low ridges, the reticulae ~5 µm in diameter, the papillae ~0.5 µm in diameter on ridges ~0.5 µm high (Fig. 13 h, i). Antheridia up to 200 µm in diameter. Chromosomes n = 14 (M. T.Casanova r933) (Fig. 13 k).   Distribution  
 Abundant in temporary wetlands in western Victoria. There is a single specimen collected from the Northern Territory (R.Breen s.n., 25 Aug. 2014 (MEL)), which keys out to Chara karolii (partly corticated axes and geminate gametangia) and is included here pending further study.   Etymology  
 Named for Kenneth G. Karol from the New York Botanical Garden, who first distinguished this species from Chara muelleri (A.Braun) F.Muell. on the basis of nucleotide analysis.   Notes  
 Chara karolii has corticated axes and regularly clustered gametangia (i.e. in twos and threes at each node), with the occasional occurrence of basal oosporangia, and granular or reticulately patterned oospores. Cortication is usually absent from the lowest axial internodes and can be restricted to the very youngest internodes. Sometimes cortication is difficult to discern and a thorough check of the upper internodes is necessary. Chara braunii, which might also occur in the Northern Territory, has no cortication whatsoever, and is generally somewhat ‘inflated’ (so that the branchlets appear like a string of sausages, constricted at the nodes). Chara muelleri is distinguished by its singular conjoined gametangia, absence of basal gametangia and more completely corticated axes.   Specimens examined  
 NORTHERN TERRITORY: creek above John Hayes Rockhole (Trepina), 25 Aug. 2014, R. Breen s.n. (MEL). VICTORIA: Muldoons Sinkhole, Budj Bim Indigenous Protected Area, 28 Mar. 2011,  M. T. Casanova r941 (MEL); Streatham–Eurumbeen Road, roadside ditch, 23 Feb. 2011, M. T. Casanova r931 (MEL) .
description: Published as part of Casanova, Michelle T. & Karol, Kenneth G., 2023, Charophytes of Australia's Northern Territory - I. Tribe Chareae, pp. 38-79 in Australian Systematic Botany 36 (1) on page 61, DOI: 10.1071/SB22023, http://zenodo.org/record/10904227