Plants medium sized, forming dense tufts or cushions, blackish-or brownish-green. Stems erect, few branched by innovations; in cross-section outer 2-3 rows of cells rather small, thick-walled, inner cells larger, walls firm, central strand present. Leaves loosely erect to appressed, ovate-oblong to narrowly long lanceolate, ending in a hyaline awn, broadly concave below, distally keeled or concave; margins plane to recurved on one side, entire; costae single, strong, long excurrent, awn smooth to toothed; lamina partially to fully bistratose, upper cells isodiametric, irregular, thick-walled; median cells similar or short rectangular and sinuose; lower and basal cells short to long rectangular, walls plane to sinuose. Gemmae absent. Autoicous. Perichaetia terminal; leaves elongate. Setae short to elongate, erect to slightly curved, twisted. Capsules shortly exserted, erect, urn ovoid to elliptical, smooth to somewhat striate; exothecial cells irregularly short oblong, ± thin-walled; stomata present at urn base, superficial; annuli in 2-4 rows; opercula short to long rostrate; peristome single, teeth 16, papillose throughout or smooth at base. Calyptrae mitrate, lobed at base. Spores spherical, smooth to papillose.

Plantas medianas, formando manojos o cojines densos, negruzcas o verde-marrones. Tallos erectos, poco ramificados por innovaciones; en corte transversal 2-3 filas externas de células bastante pequeñas, con paredes gruesas, células internas mayores, con paredes firmes, cordón central presente. Hojas laxamente erectas a adpresas, ovado-oblongas a angostamente largo lanceoladas, terminando en una arista hialina, anchamente cóncavas abajo, distalmente carinadas o cóncavas; márgenes planos a recurvados sobre un lado, enteros; costa simple, fuerte, largo excurrente, arista lisa a dentada; lámina parcial hasta completamente biestratificada, células superiores isodiamétricas, irregulares, con paredes gruesas; células mediales similares o corto-rectangulares y sinuosas; células inferiores y basales corto a largo rectangulares, paredes planas hasta sinuosas. Yemas ausentes. Autoicas. Periquecios terminales; hojas alargadas. Setas cortas hasta alargadas, erectas a escasamente curvadas, torcidas. Cápsulas brevemente excertas, erectas, urna ovoide hasta elíptica, lisas hasta algo estriadas; células exoteciales irregularmente corto-oblongas, paredes ± delgadas; estomas en la base de la urna, superficiales; anillos en 2-4 filas; opérculo corto- hasta largo-rostrado; peristoma simple, con 16 dientes, totalmente papilosos o lisos en la base. Caliptra mitrada, base lobada. Esporas esféricas, lisas hasta papilosas.

Keys modified from Muñoz (1999).

1. Leaves strongly plicate on both sides of costa … 2.

1. Leaves not plicate or only weakly so … 3.

2. Setae curved; capsules asymmetric and ventricose at base, gymnostomous; calyptrae mitrate, not exceeding further down than the capsule mouth, not plicate … G. trinervis

2. Setae straight; capsules symmetric with the seta centrally placed at base, peristome present; calyptrae campanulate, extending below capsule mouth, plicate … see Coscinodon

3. Capsules asymmetric and ventricose at base; seta eccentrically attached to the capsule, curved, shorter than capsule … G. anodon

3. Capsules symmetric OR specimens sterile; seta centrally attached to the capsule and, if curved, longer than the capsule… 4.

4. Proximal marginal leaf cells with all walls similar, thin-walled … 5.

4. Proximal marginal leaf cells with transverse walls thicker than longitudinal walls … 7.

5. Margins plane throughout or incurved above, no trace of recurvation … G. donniana

5. Margins recurved, at least on one side for part of its length … 6.

6. Longest hair-points longer than 0.3 mm, most of the leaves piliferous; autoicous, made buds small and lateral, hidden just below perichaetia; setae curved (sporophytes generally present) … G. fuscolutea

6. Longest hair-point to 0.3 mm long, most of the leaves muticous; dioicous, male buds terminal; setae straight … G. elongata

7. All leaves constantly muticous (without a point or awn) … G. atrata

7. At least perichaetial leaves with a trace of a hair-point … 8.

8. Margins plane or incurved … 9.

8. Margins recurved, at least on one side for part of its length … 11.

9. Distal half of lamina unistratose, only 1 or 2 marginal rows 2-stratose … G. pseudoanodon

9. Distal half of lamina 2 to 3(4)-stratose … 10.

10. Costae semicircular (cross-section), scarcely prominent on dorsal surface, occasionally the same thickness as lamina, scarcely differentiated … G. tetrestina

10. Costae elliptical (cross-section), prominent on dorsal surface … G. reflexidens

11. Ventral layer of costae 2-6 cells wide, cross-section of costae reniform … G. longirostris (see also G. herzogii)

11. Ventral layer of costae 2 cells wide, cross-section of costae semicircular, never reniform … 12.

12. Laminar cells bulging (cross-section) … G. reflexidens

12. Laminar cells not bulging (cross-section) … 13.

13. Lamina mostly unistratose in upper 2/3, with bistratose margins and/or occasional and small 2-stratose patches … 14.

13. Lamina 2-3(4)-stratose for most of upper 2/3 … 16.

14. Leaf section forming an angle less than 30º, parallel at the junction with the costa, furrow very narrow … G. navicularis

14. Leaf section forming an angle greater than 45º, divergent at base, furrow more open … 15.

15. Propagula sessile on lamina, seldom on the costa, not stalk remaining after propagula liberation, which causes leaf destruction; lamina bistratose at margins and in streaks; plants less than 3 cm; spores minutely granulose, apparently smooth under light microscope … G. trichophylla

15. Propagula on stalks at dorsal base of costa, the stalk 1(2) cells long remaining attached to the costa after propagula liberation, which does not affect the leaf; lamina unistratose except sometimes 2-stratose in 1-2 rows at margin; plants to 8 cm; spores coarsely and distinctly granulose under compound microscope … G. austrofunalis

16. Leaf section forming an angle less than 30º, parallel at the junction with the costa, furrow very narrow … G. navicularis

16. Leaf section forming an angle greater than 50º, divergent at base, furrow open … 17.

17. Leaves appressed, straight; setae straight; capsules immersed; autoicous … G. molesta

17. Leaves flexuous; setae curved; capsules exserted; dioicous … G. bicolor