Chloridoideae

Pink pappusgrass Pappophorum bicolor, copyright Forrest Smith.

Belongs within: Poaceae.
Contains: Muhlenbergia, Zoysieae, Sporobolus, Chlorideae, Eragrostis, Triodia.

The Chloridoideae is a clade of mostly C₄ grasses supported by molecular analysis but with no identified morphological synapomorphies as yet. However, the clade of chloridoids excluding 'Merxmuellera' rangei and Centropodia is supported by the presence of 'chloridoid-type' microhairs with short and wide apical cells (Grass Phylogeny Working Group 2001). Subgroups include the Pappophoreae, characterised by the production of many-veined, many-awned lemmas on a tough rachilla with the florets all falling together from the glumes. The Eragrostideae bear unspecialised spikelets usually with several florets, three-veined lemmas, and a rather cartilaginous texture.

Characters (from Grass Phylogeny Working Group 2001): Plants annual or perennial (rhizomatous, stoloniferous, caespitose or decumbent), herbaceous (rarely woody), of dry climates, especially in the tropics and subtropics, also found in the temperate zone. Culms solid or hollow. Leaves distichous; abaxial ligule usually absent, rarely present as a line of hairs; adaxial ligule a fringed or less commonly unfringed membrane; blades relatively narrow, without pseudopetioles, venation parallel; sheaths usually non-auriculate. Inflorescences paniculate, paniculate with spicate branches, racemose, or spicate, bracts outside of the spikelets absent. Spikelets bisexual or sometimes unisexual (if so the plants dioecious or monoecious), with glumes 2, rarely a sterile lemma, and female-fertile florets 1 to many, apical reduction usually present, usually laterally compressed, sometimes dorsally compressed, usually disarticulating above the glumes (below in a few Eragrostis species); lemma lacking uncinate macrohairs, if awned, the awns single or if multiple, lacking a basal column; palea well developed; lodicules 2 or absent, fleshy, glabrous; stamens 1 to 3; ovary glabrous, apical appendage absent, haustorial synergids absent, styles 2, free, close, stigmas 2. Caryopsis with the pericarp often free or loose; hilum short; endosperm hard, without lipid, containing simple or compound starch grains; embryo large or rarely small, epiblast present or rarely absent, scutellar cleft present, mesocotyl internode elongated, embryonic leaf margins meeting or rarely overlapping. Foliar mesophyll usually radiate, without an adaxial palisade layer, fusoid cells absent, arm cells absent; Kranz anatomy present; midrib simple; adaxial bulliform cells present. Foliar stomata with dome-shaped or triangular subsidiary cells; bicellular microhairs present, usually chloridoid-type; papillae absent or present.

<==Chloridoideae [Eragrostoideae, Pappophoroideae]
    |--+--‘Merxmuellera’ rangei GPWG01
    |  `--Centropodia glauca GPWG01
    `--+--+--+--Zoysieae S06
       |  |  `--+--Sporobolus GPWG01
       |  |     `--Chlorideae GPWG01
       |  `--Distichlis GPWG01
       |       |--D. scoparia CLB06
       |       `--D. spicata (Linnaeus) Greene 1887 S06 (see below for synonymy)
       |            |  i. s.: D. s. f. hirta [=D. hirta Phil. 1873] S06
       |            |         D. s. var. mendozina [=D. thalassica var. mendozina] S06
       |            |         D. s. var. thalassica [=Megastachya thalassica, Uniola thalassica] S06
       |            |--D. s. ssp. spicata GPWG01
       |            `--D. s. ssp. stricta GPWG01
       `--+--+--Uniola GPWG01
          |  |    |--U. latifolia V72
          |  |    `--U. paniculata GPWG01
          |  `--Eragrostideae GPWG01
          |       |--Eragrostis GPWG01
          |       |--Triodia M99
          |       `--Dactyloctenium M99
          |            |--D. aegyptium (Lin.) Richter 1890 (see below for synonymy) S06
          |            |--D. mucronatum C55
          |            |--D. radulans M99
          |            `--D. scindicum PP07
          `--Pappophoreae GPWG01
               |--Calamochloa Fournier 1877 S56
               |    `--C. filifolia S56
               |--Enneapogon S56
               |    |--E. cenchroides PP07
               |    |--E. desvauxii PP07
               |    |--E. nigricans Z93
               |    |--E. pallidus LK14
               |    |--E. persicus PP07
               |    |--E. polyphyllus LK14
               |    |--E. purpurascens LK14
               |    `--E. schimperanus PP07
               `--Pappophorum GPWG01
                    |--P. alopecuroideum S06
                    |    |--P. a. f. alopecuroideum S06
                    |    `--P. a. f. coerulescens S06
                    |--P. bicolor GPWG01
                    `--P. mucronulatum S06
                         |  i. s.: P. m. f. elatior S06
                         |         P. m. f. pumila Hackel in Stuckert 1906 S06
                         |         P. m. f. spiculis-minoribus Hackel in Stuckert 1906 S06
                         |--P. m. var. mucronulatum S06
                         `--P. m. var. subsimplex Hackel in Stuckert 1906 S06

Chloridoideae incertae sedis:
  Tridens GPWG01
    |--T. albescens HW96
    |--T. flavus GPWG01 [=Triodia flava V72]
    `--T. muticus H93
  Muhlenbergia GPWG01
  Eustachys GPWG01
  Cynodon [Cynodonteae] GPWG01
    |--C. dactylon (Linnaeus) Persoon 1805 PL04
    |--C. nlemfuensis LK14
    |--C. plectostachyus H93
    `--C. transvaalensis H93
  Lepturus [Leptureae] GPWG01
    |--L. incurvatus C06
    `--L. repens C78
  Orcuttia [Orcuttieae] GPWG01
    |--O. californica H93
    |--O. inaequalis [=O. californica var. inaequalis] H93
    |--O. pilosa H93
    |--O. tenuis H93
    `--O. viscida [=O. californica var. viscida] H93

Dactyloctenium aegyptium (Lin.) Richter 1890 [=Cynosurus aegyptius Lin. 1753, Eleusine aegyptia (Lin.) Pers. 1805; incl. Dactyloctenium aegyptiacum Willd. 1809] S06

Distichlis spicata (Linnaeus) Greene 1887 S06 [=Uniola spicata Linnaeus 1853 S06, Brizopyrum spicatum S06; incl. U. distichophylla S06, Distichlis spicata var. divaricata H93, D. maritima Rafin. 1819 S06, Poa michauxii S06, D. spicata var. nana H93, D. spicata var. stolonifera H93]

*Type species of generic name indicated

REFERENCES

[C55] Candolle, A. de. 1855. Géographie Botanique Raisonée: Ou exposition des faits principaux et des lois concernant la distribution géographique des plantes de l’époque actuelle vol. 2. Librairie de Victor Masson: Paris.

[C06] Cheeseman, T. F. 1906. Manual of the New Zealand Flora. John Mackay, Government Printer: Wellington.

[C78] Clunie, N. M. U. 1978. The vegetation. In: Womersley, J. S. (ed.) Handbooks of the Flora of Papua New Guinea vol. 1 pp. 1–11. Melbourne University Press: Carlton South (Australia).

[CLB06] Cutrera, A. P., E. A. Lacey & C. Busch. 2006. Intraspecific variation in effective population size in talar tuco-tucos (Ctenomys talarum): the role of demography. Journal of Mammalogy 87 (1): 108–116.

[GPWG01] Grass Phylogeny Working Group. 2001. Phylogeny and subfamilial classification of the grasses (Poaceae). Annals of the Missouri Botanical Garden 88 (3): 373–457.

[H93] Hickman, J. C. (ed.) 1993. The Jepson Manual: Higher Plants of California. University of California Press: Berkeley (California).

[HW96] Hicks, A. L., & R. F. Whitcomb. 1996. Diversity of the leafhopper (Homoptera: Cicadellidae) fauna of northern Chihuahuan grasslands, with emphasis on gypsum grasslands and description of a new species of Athysanella (Cicadellidae: Deltocephalinae). Proceedings of the Entomological Society of Washington 98 (1): 145–157.

[LK14] Lyons, M. N., G. J. Keighery, L. A. Gibson & T. Handasyde. 2014. Flora and vegetation communities of selected islands off the Kimberley coast of Western Australia. Records of the Western Australian Museum Supplement 81: 205–244.

[M99] Matthews, M. 1999. Heliothine Moths of Australia: A guide to bollworms and related noctuid groups. CSIRO Publishing.

[PP07] Pandey, R. P., & P. M. Padhye. 2007. Studies on phytodiversity of Arid Machia Safari Park-Kailana in Jodhpur (Rajasthan). Bulletin of the Botanical Survey of India 4: 15–78.

[PL04] Pohl, G., & I. Lenski. 2004. Zur Verbreitung und Vergesellschaftung von Pennisetum orientale Rich. in Nordeuböa (Griechenland) (Poaceae, Paniceae). Senckenbergiana Biologica 83 (2): 209–223.

[S56] Sohns, E. R. 1956. Calamochloa: a Mexican grass. Journal of the Washington Academy of Sciences 46 (4): 109–112.

[S06] Stuckert, T. 1906. Segunda contribución al conocimiento de las gramináceas Argentinas. Anales del Museo Nacional de Buenos Aires, serie 3, 6: 409–555.

[V72] Voss, E. G. 1972. Michigan Flora. Part I. Gymnosperms and Monocots. Cranbrook Institute of Science and University of Michigan Herbarium.

[Z93] Zimmerman, E. C. 1993. Australian Weevils (Coleoptera: Curculionoidea) vol. 3. Nanophyidae, Rhynchophoridae, Erirhinidae, Curculionidae: Amycterinae, literature consulted. CSIRO Australia.

Last updated: 22 March 2020.