Family name: Thurniaceae A. Engler
Synonym(s): Prioniaceae S. L. Munro & H. P. Linder
Common name(s): thurnia family
*Number of genera/species: 2/4
List of genera records in GRIN-Global
seed
Fruit a loculicidalloculicidal:
type of capsular dehiscence, opening longitudinally through the locules (compare septicidal)
capsulecapsule:
a dry, dehiscent fruit derived from a compound ovary, 1–15 mm long, triangulartriangular:
2D shape—three relatively straight sides with distinct corners; more angular than teardrop-shaped, angledangular:
2D shape—having sides that meet at acute or obtuse angles
in transection, usually 3 seeded, sometimes hypanthium present. Pericarppericarp:
fruit wall or fruit coat
smooth.
Seeds fusiformfusiform:
spindle-shaped; broadest at the middle and tapering at both ends (ovateovate:
2D shape—egg-shaped in outline, widest point is towards one end of the organ, the other end tapers gradually, attachment at or near the broad end (compare obovate, ovoid) to broadly ovateovate:
2D shape—egg-shaped in outline, widest point is towards one end of the organ, the other end tapers gradually, attachment at or near the broad end (compare obovate, ovoid) in Prionium), tereteterete:
approximately circular in cross section; width and thickness approximately equal
(triagonal in Prionium) in transection, 5–8 mm long, hairlike appendages present at both ends (not appendiculate in Prionium). Seed coat with short, straight hairs (glabrousglabrous:
without hairs
in Prionium).
Embryo well developed, linearlinear:
(shape) long, narrow, and uniform in width; (of embryo) embryo is straight and much longer than wide to broad, straight, 0.3 times the length of the endosperm (or nearly as long in Prionium).
Endosperm copious, mealymealy:
loose, dry, and disintegrating in finely granular
pieces like meal or flour
.
Fruit | |
Type | capsulecapsule: a dry, dehiscent fruit derived from a compound ovary ![]() |
Size range | 10–15 mm long |
Shape(s) | tri angularangular: 2D shape—having sides that meet at acute or obtuse angles |
Surface relief | smooth |
Seed | |
Size range | 5–8 mm long |
Shape(s) | fusiformfusiform: spindle-shaped; broadest at the middle and tapering at both ends ![]() 2D shape—egg-shaped in outline, widest point is towards one end of the organ, the other end tapers gradually, attachment at or near the broad end (compare obovate, ovoid) ![]() 2D shape—egg-shaped in outline, widest point is towards one end of the organ, the other end tapers gradually, attachment at or near the broad end (compare obovate, ovoid) ![]() |
Surface relief | densely pubescentpubescent: surface relief—bearing hairs , glabrousglabrous: without hairs |
Unique features | In Thurnia, seeds fusiformfusiform: spindle-shaped; broadest at the middle and tapering at both ends ![]() surface relief—bearing hairs with hairlike appendages at both ends. In Prionium, seeds ovateovate: 2D shape—egg-shaped in outline, widest point is towards one end of the organ, the other end tapers gradually, attachment at or near the broad end (compare obovate, ovoid) ![]() 2D shape—egg-shaped in outline, widest point is towards one end of the organ, the other end tapers gradually, attachment at or near the broad end (compare obovate, ovoid) ![]() |
Other | |
Embryo | well developed, linearlinear: (shape) long, narrow, and uniform in width; (of embryo) embryo is straight and much longer than wide ![]() |
Nutritive tissue | endosperm copious, mealymealy: loose, dry, and disintegrating in finely granular pieces like meal or flour |
Tropical South America.
Distribution map courtesy of Angiosperm Phylogeny Website.
Baskin and Baskin 2021Baskin and Baskin 2021:
Baskin C and Baskin J. 2021. Relationship of the lateral embryo (in grasses) to other monocot embryos: A status up-grade. Seed Science Research 31 (3): 199-210. doi:10.1017/S0960258521000209; Dahlgren et al. 1985Dahlgren et al. 1985:
Dahlgren RMT, Clifford HT, and Yeo PF. 1985. The families of the monocotyledons: structure, evolution, and taxonomy. Springer-Verlag, Berlin. 520 pp.; Kirkbride et al. 2006Kirkbride et al. 2006:
Kirkbride JH, Jr, Gunn CR, and Dallwitz MJ. 2006. Family guide for fruits and seeds, vers. 1.0. Accessed September 2020-January 2022. URL: https://nt.ars-grin.gov/seedsfruits/keys/frsdfam/index.cfm .; Kubitzki et al. 1990+Kubitzki et al. 1990+:
Kubitzki K et al., eds. 1990+. The families and genera of vascular plants. 7+ vols. Berlin etc.; Maas and Maas 2005Maas and Maas 2005:
Maas PJM and Maas H. 2005. Flora Da Reserva Ducke, Amazonas, Brasil: Thurniaceae. Rodrigueacute;sia 56: 207.; Stevenson and Loconte 1995Stevenson and Loconte 1995:
Stevenson DW and Loconte H. 1995. A cladistic analysis of monocot families. In: Rudall PJ, Cribb PJ, Cutler DF, and Humphries CJ, eds. Monocotyledons: Systematics and Evolution. Royal Botanic Gardens, Kew.
*The number of genera and species is based on Christenhusz and Byng 2016Christenhusz and Byng 2016:
Christenhusz MJM and Byng JW. 2016. The number of known plant species in the world and its annual increase. Phytotaxa 261 (3): 201-217. https://doi.org/10.11646/phytotaxa.261.3.1, which may differ from the number of genera in GRIN-Global.