Monograph of Diplachne (Poaceae, Chloridoideae, Cynodonteae)

Abstract

Diplachne P. Beauv. comprises two species with C4 (NAD-ME) photosynthesis. Diplachne fusca has a nearly pantropical-pantemperate distribution with four subspecies: D. fusca subsp. fusca is Paleotropical with native distributions in Africa, southern Asia and Australia; the widespread Australian endemic D. f. subsp. muelleri; and D. f. subsp. fascicularis and D. f. subsp. uninervia occurring in the New World. Diplachne gigantea is known from a few widely scattered, older collections in east-central and southern Africa, and although Data Deficient clearly is of conservation concern. A discussion of previous taxonomic treatments is provided, including molecular data supporting Diplachne in its newer, restricted sense. Many populations of Diplachne fusca are highly tolerant of saline substrates and most prefer seasonally moist to saturated soils, often in disturbed areas. Some populations of Diplachne fusca in southern Asia combine nitrogen-fixation, high salinity tolerance and palatibilty to livestock, which should be pursued with further research for purposes of soil reclamation. Diplachne fusca subsp. uninervia is the most invasive of the subspecies and is becoming weedy in some non-native areas, including in the Old World. This monograph provides detailed descriptions of all taxa, a key to the species and subspecies, geographic distributions and information on the anatomy of leaves, stems, lemmatal micromorphology and discussions of the chromosome numbers. Lectotypes are designated for: Atropis carinata Grisb.; Diplachne acuminata Nash; Diplachne capensis (Nees) Nees var. concinna Nees; Diplachne capensis (Nees) Nees var. obscura Nees, Diplachne capensis (Nees) Nees var. prolifera subvar. minor Nees, Diplachne halei Nash, Diplachne maritima E.P. Bicknel, Diplachne muelleri Benth., Diplachne reverchonii Vasey, Diplachne tectoneticola Backer, Leptochloa imbricata Thurb., Leptochloa neuroglossa Peter, Leptochloa uninervia var. typica fo. abbreviata Parodi, Triodia ambigua R. Br. and Triodia parviflora R. Br.

Phylogeny, classification, and biogeography of Afrotrichloris, Apochiton, Coelachyrum, Dinebra, Eleusine, Leptochloa, Schoenefeldia, and a new genus, Schoenefeldiella (Poaceae: Chloridoideae: Cynodonteae: Eleusininae)

“…), and Trigonochloa P.M. Peterson & N. Snow (2 spp.) (Peterson et al, 2012(Peterson et al, , 2014c(Peterson et al, , 2015aSnow et al, 2013Snow et al, , 2018Soreng et al, 2017).…”

Comparative Plastomes and Phylogenetic Analysis of Cleistogenes and Closely Related Genera (Poaceae)

“…Cleistogenes is considered as an incertae sedis genus due to its different placement in ITS, plastid, and combined trees ( Peterson et al, 2010 ; Soreng et al, 2015 ). Recent studies show that Aeluropodinae ( Aeluropus and Odyssea ), Triodiinae ( Triodia ), and Orininae ( Cleistogenes and Orinus ) form a monophyletic clade ( Peterson et al, 2017 ; Soreng et al, 2017 ), while the relationships among them are incongruence. Cleistogenes is sister to Orinus in an ITS tree, and in a combined tree ( Peterson et al, 2010 , 2016 ).…”

Emergence of a new salt-tolerant alien grass along roadsides? Occurrence of Diplachne fusca subsp. fascicularis (Poaceae) in Hungary

“…The species Diplachne fusca has a secondary cosmopolitan range. It can be divided into four subspecies (Snow et al 2018). The native range of subspecies fascicularis extends from Southern Canada to Argentina.…”

“…With the help of its symbiotic bacteria D. fusca subsp. fascicularis is able to fix N2 (Zafar et al 1986, Reinhold-Hurek et al 1993, furthermore it is a plant species of the C4 photosynthetic pathway (Snow et al 2018). These characters can help the species to adapt even to extreme habitat conditions.…”

“…N. Snow) on the roadside of the E40 primary main road near Cegléd (central Hungary). The taxon was identified according to Snow et al 2018. This species has a native distribution range restricted to the Americas, spanning the area from southern Canada to Argentina.…”