Plants perenial, loosely caespitose. Culms (37)47–80(110) cm high with 2–3 nodes; nodes glabrous; basal branching intravaginal.
Basal leaf sheaths disintegrating into a brownish mass of reticulate fibers; auricles (0.1)0.3–0.7(0.8) mm long); blades linear; narrow; (1)1.6–2.6(3.1) mm wide, rolled, disarticulating from the sheaths; sheaths of innovation leaves with connate margins.
Inflorescences spikelike, (5)8–14(17) cm long), with (6)7–13(15) nodes, with solitary spikelets; disarticulation below the florets.
Spikelets (11)12–19(21) mm long, with 5-10 florets. Glumes subequal to equal, lanceolate, leathery, shorter than the adjacent lemmas, glabrous; acute, not keeled, awned, awn 0.5–1.3 mm long; lower glume 2–4 veined; upper glume 3–6 veined. Lemmas glabrous, not keeled, awned, awn 3-9 mm long; palea equalling to slightly shorter than the lemma, 2-veined; 2-keeled, keels ciliate distally. Lodicules 2, ciliate. Stamens 3. Anthers 4.2–6(6.3) mm long. Ovary hairy; stigmas 2.
Caryopses 4.5–5.5 mm long, adhering to the lemma; not grooved; with hairs confined to a terminal tuft; hilum long-linear.
[Description developed by modifying information in Watson et al. 208]
There is only one species in Peridictyon, P. sanctum
Endemic to the Northern Greece and southwestern Bulgaria
The key in Flora Europaea indicates that the spikelets in Peridictyon and Festucopsis are radial to the rachis, but the descriptions do not include this comment and it is not evident on the only specimens of Festucopsis that I have seen. I have not seen any specimens of Peridictyon(yet).
The only species of Peridictyon was included in Festucopsis until Seberg et al. (1991) recommended treating it as a distinct genus.
Peridictyon sanctum (Janka) Seberg, Fred. & Baden
A more comprehensive description is desirable.
Seberg O., S. Fredriksen, C. Baden, and and I. Linde-Laursen I. 1991. Peridictyon, a new genus from the Balkan peninsula, and its relationship with Festucopsis (Poaceae). Willdenow 21: 87-104.
Watson, L., and Dallwitz, M.J. 2008. The grass genera of the world: descriptions, illustrations, identification, and information retrieval; including synonyms, morphology, anatomy, physiology, phytochemistry, cytology, classification, pathogens, world and local distribution, and references. Version: 25th November 2008. http://delta-intkey.com’.