Cephalocarpus Nees

Costa, Suzana M., Vitta, Fabio A., Thomas, William W., Muasya, A. Muthama, Morokawa, Rosemeri, Bittrich, Volker, Shepherd, George J. & Do Amaral, Maria Do Carmo E., 2021, An updated generic circumscription for Cryptangieae (Cyperaceae, Poales) based on a molecular phylogeny and a morphological character reconstruction, Phytotaxa 483 (3), pp. 211-228 : 223-224

Cephalocarpus Nees , Flora Brasiliensis (Martius) 2(1): 162 (1842).

Type species: Cephalocarpus dracaenula Nees

Lagenocarpus subgen Cephalocarpus (Nees) H. Pfeiff., Repertorium Specierum Novarum Regni Vegetabilis 18: 91 (1922).

Everardia Ridley, Timehri 5: 210 (1886). Syn. nov. Type species: Everardia montana Ridley

Monoecious, rarely dioecious herbs, with elongate caudex. Leaf blades well developed, linear to lanceolate; leaf sheaths shreading to form a net-like tunic. Inflorescence lateral, solitary or many at a same prophyll, head or paniclelike. Involucral bracts leaf-like, with linear-lanceolate to lanceolate blades. Paracladia superficially monomorphic: male and female spikelets separate or mixed in the paracladia of monoecious species; female spikelets most frequently at a terminal position. Male spikelets 1–9 flowered; stamens 2–6 (7–9) per flower. Female spikelets 1-flowered, 4–7(9) glumes; stigmas 3 (rarely 2 or 4-fid). Glumes spirally or sub-distichally arranged. Fruits (nutlet) sessile or stipitate, obovoid, ellipsoid, oblong or ovoid, trigonous, generally trisulcate, glabrous or minutely to densely ciliate especially at the apex (including the beak), main body continuous to the beak or with a constriction zone between the beak and the main body; hypogynous scales well-developed, long or shortly fimbriate (rarely sparsely ciliate); beak long or short conical, glabrous, minute ciliate to densely ciliate, persistent or caducous. ( Figure 2 A-C)

Cephalocarpus occurs on the Guiana Shield and surrounding areas in northern South America, in Venezuela, Guyana, Colombia, Brazil and Suriname; additionally some species occurs in mountains adjacent to the Andes, in Peru and Ecuador, with similar edaphoclimatic conditions—“Cordillera del Condor”. Its species are more frequent and diverse at higher elevations on nutrient poor sandy or rocky soils. Total number of species: 18.

According to our phylogenetic analysis, Cephalocarpus (sensu Koyama 2003) should include Everardia (sensu Koyama 2003) to become monophyletic. Cephalocarpus was morphologically supported mainly by the head-like inflorescence and the constricted region between the beak and fruit main portion ( Koyama & Maguire 1965; Koyama 2003). A careful look at the inflorescence reveals that it is just an extremely contracted version of the Everardia (sensu Koyama 2003) inflorescence. Six recently discovered species (Costa et al., unpublished data) reinforce our results: the new species present mixed inflorescence and nutlet character states of Everardia (sensu Koyama 2003) and Cephalocarpus (sensu Koyama 2003) .

1. Cephalocarpus angustus (N.E.Brown) S.M.Costa , comb. nov.

Basionym: Everardia angusta N.E.Brown, Trans. Linn. Soc. of London, 2nd series: Botany 6: 73 (1901).

2. Cephalocarpus confertus Gilly, Bull. Torrey Bot. Club 69 (4): 293-294 (1942).

3. Cephalocarpus debilis (T.Koyama & Maguire) S.M.Costa , comb. nov.

Basionym: Everardia debilis T.Koyama & Maguire, Memoirs of the New York Botanical Garden 12: 32 (1965).

4. Cephalocarpus diffusus (T.Koyama & Maguire) S.M.Costa , comb. nov.

Basionym: Everardia diffusa T.Koyama & Maguire, Mem. New York Bot. Gard. 12: 21 (1965).

5. Cephalocarpus distichous (T.Koyama & Maguire) S.M.Costa , comb. nov.

Basionym: Everardia disticha T.Koyama & Maguire, Mem. New York Bot. Gard. 12: 25 (1965).

6. Cephalocarpus dracaenula Nees , Flora brasiliensis (Martius) 2 (1): 162–163 (1842).

7. Cephalocarpus duidae (Gilly) S.M.Costa , comb. nov.

Basionym: Everardia duidae Gilly, Bull. Torrey Bot. Club 68: 30 (1941).

8. Cephalocarpus erecto-laxus (T.Koyama & Maguire) S.M.Costa , comb. nov.

Basionym: Everardia erecto-laxa T.Koyama & Maguire, Mem. New York Bot. Gard. 12: 27 (1965).

9. Cephalocarpus flexifolium (Gilly) S.M.Costa , comb. nov.

Basionym: Didymiandrum flexifolium Gilly, Bull. Torrey Bot. Club 68: 331 (1941).

10. Cephalocarpus longibracteatus Gilly , Brittonia 3: 153 (1939).

11. Cephalocarpus longifolius (Gilly) S.M.Costa , comb. nov.

Basionym: Everardia longifolia Gilly , Brittonia 3(2): 153 (1939).

12. Cephalocarpus maguireanus (T.Koyama) S.M.Costa , comb. nov.

Basionym: Everardia maguireana T.Koyama, Mem. New York Bot. Gard. 18: 23 (1969).

13. Cephalocarpus montanus (Ridley) S.M.Costa , comb. nov.

Basionym: Everardia montana Ridley, Timehri 5:210 (1886).

14. Cephalocarpus obovoideus T.Koyama, Mem. New York Bot. Gard. 18 (2): 22-23 (1969).

15. Cephalocarpus ptariensis (Gilly) S.M.Costa , comb. nov.

Basionym: Everardia ptariensis Gilly, Fieldiana Bot. 28(1): 55 (1961).

16. Cephalocarpus recurviglumis (T.Koyama & Maguire) S.M.Costa , comb. nov.

Basionym: Everardia recurvigluma T.Koyama & Maguire, Mem. New York Bot. Gard. 12: 23 (1965).

17. Cephalocarpus rigidus Gilly ex Gleason & Killip , Brittonia 3: 152 (1939).

18. Cephalocarpus vareschii (Maguire) S.M.Costa , comb. nov.

Basionym: Everardia vareschii Maguire, Acta Biologica Venezuelica 2(6): 43 (1957).

Figures

FIGURE 2. Cryptangieae general morphology.A. Cephalocarpus confertus (habit), B-C. Cephalocarpus montanus habit (B) and caudex in cross section (C); D-E. Krenakia minarum habit (D) and detail of leaves reduced to sheaths (E); F-G. Exochogyne amazonica with mature male (F) and female (G) spikelets; H. Cryptangium verticillatum male spikelets; I. Krenakia sp. spikelets. J. Lagenocarpus rigidus inflorescence (female spikelets apical and in rigid peduncles and male spikelets basal and in flexible peduncles); K. Cephalocarpus confertus inflorescence detail (male and female spikelets at the same cluster); L. Cephalocarpus montanus uniflowered spikelets with immature nutlets.