Oncothecaceae

Disclaimer

Content is from 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 .
, without modification. Updates are forthcoming.

Taxonomy

Oncothecaceae Kobuski ex Airy Shaw

Common name: Onocotheca Family.

Number of genera: 1 genus.

Number of species (Mabberley 1997): 2 species (Oncotheca balansae Baill., O. humboldtiana (Guillaumin) Morat & Veillon).

Disseminule

Fruit (intact or entire).

Description

Fruits: Pistil(s) compound; 1; 1-pistillate; with carpels united. Fruit pericarpium; simple; drupedrupe:
(indehiscent drupe) a fleshy, indehiscent fruit with one more hard pits enclosing seeds, derived from single, superior, simple or compound ovary; (dehiscent drupe) a fruit with a dry or fibrous to fleshy or leathery outer husk that early to tardily breaks apart (or opens), exposing one or more nutlike pits enclosing the seeds
; without persistent central column; not within accessory organ(s); 1-seeded to more than 1 but less than 10-seeded; 1–5-seeded; from 1–5 cm long; 1.5–2 cm long; with 5-carpellate; with carpels united; with carpels remaining united at maturity; with carpels not radiating at maturity; with carpels remaining connected at stylestyle:
in a flower, the narrow and elongated part of the pistil between the stigma and the ovary; sometimes persisting in fruit
; without sterilesterile:
lacking male and/or female reproductive parts; also, not producing fruit or seed
carpels, or with sterilesterile:
lacking male and/or female reproductive parts; also, not producing fruit or seed
carpels; not sulcatesulcate:
surface relief—having one or more elongate, relatively narrow and shallow depressions or grooves
; apexapex:
the point farthest from the point of attachment, or the "tip" of an organ
not beaked; indehiscentindehiscent:
not opening on its own, as in a fruit
. Epicarpepicarp:
outer layer of fruit wall or pericarp, if divided into layers; note here used synonymously with exocarp
golden yellow (dark green previously); durable; glabrousglabrous:
without hairs
; without armature; without wing(s); without apicalapical:
at or pertaining to the end of the seed or fruit distal from its point of attachment (i.e., base)
respiratory hole. Mesocarpmesocarp:
the middle layer of the pericarp, if divided into layers
present; leatheryleathery:
texture—moderately thick, tough, and very pliable
, or thin and fleshy; composed of 1 unified layer; without lactiform cavity system; & endocarpendocarp:
the inner layer of the pericarp, if divided into layers
sharply differentiated. Endocarpendocarp:
the inner layer of the pericarp, if divided into layers
present; not separating from exocarpexocarp:
outer layer of fruit wall or pericarp, if divided into layers; note here used synonymously with epicarp
; woodywoody:
texture—consisting mainly of indurate lignified tissues, characteristic of or resembling wood
; not splitting into 1-seeded pyrenes; stone plurilocular; stone 5-loculate; without wing; without operculumoperculum:
a dehiscent cap (or lid) of a seed or fruit that opens during germination or dehiscence
; without secretory cavities; without mechanism for seedling escape; without grooves; without longitudinallongitudinal:
of or relating to length or the lengthwise dimension
ridges. Funiculusfuniculus:
(alt. funicle) stalk connecting the ovule (later seed) to the ovary (later fruit) placenta
short; short without seed bearing hookswith hooks:
bristles or spines with curved or backwards pointing tips, or with secondary bristles along their length
(retinacula); not persisting in fruit after seed shed.

Seeds: Arilaril:
(broad sense) appendicular structure that wholly or partly envelops a seed and is produced from or a modification of the funicle, raphe, or outer integument; usually fleshy or pulpy, sometimes spongy or tufted-capillate, often brightly colored
absent. Seed larger than minute; 1 to less than 5 mm long, or 5 to less than 10 mm long, or 10 to less than 25 mm long; 4.5–15 mm long; little smaller at embryo end oblongoblong:
2D shape—much longer than broad with nearly parallel sides, corners are rounded
, or 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)
; not bowl shaped; not nutlike; without winglike beakbeak:
a usually firm, terminal appendage, sometimes tapered
; without caudatecaudate:
tapering to a long, tail-like appendage
appendage(s); at maturity with food reserves; with endosperm; without canavanine. Sarcotestasarcotesta:
pulpy or fleshy outer layer of the seed coat, simulates aril
absent. Testatesta:
seed coat
present; without markedly different marginalmarginal:
at, on, or close to the margin or border
tissue; without fleshy or leatheryleathery:
texture—moderately thick, tough, and very pliable
layer over hard layer; without crease or line separating cotyledons from hypocotyl-radicle; without notch along margin where cotyledons from hypocotyl-radicle tip approach each other; without glands; without bristles; glabrousglabrous:
without hairs
; without wings; without collar; without operculumoperculum:
a dehiscent cap (or lid) of a seed or fruit that opens during germination or dehiscence
; colored; monochrome; white (ish); not becoming mucilaginousmucilaginous:
resembling mucilage; moist and sticky
when wetted; surrounding food reserve. Endosperm copious; soft; smooth; without fatty acid containing cyclopropene; without apicalapical:
at or pertaining to the end of the seed or fruit distal from its point of attachment (i.e., base)
lobes; without chlorophyll; without isodiametric faceted surface; without odor. Embryo differentiated from food reserve; well developed; 1 per seed; partially filling testatesta:
seed coat
(with food reserve); 0.7–0.8 times the length of food reserve; at one end of seed not extending into a depression or cup; axileaxile:
on or of the axis
and centric, or basalbasal:
at or pertaining to the point of attachment; (of embryo) embryo occupies one end of the seed
; linearlinear:
(shape) long, narrow, and uniform in width; (of embryo) embryo is straight and much longer than wide
; straight; parallel to seed length; embedded in endosperm; with cotyledons gradually connected to hypocotyl-radicle; without coleorhiza; without simmondsin; without stomata; not green; with 2 or more cotyledons. Cotyledons 2, or 3; tiny; 0.2 times length of embryo (estimated); as wide as hypocotyl-radicle; 1 times wider than hypocotyl-radicle; partially concealing hypocotyl-radicle; not foliaceous; thin; flat; smooth; with apicesapex:
the point farthest from the point of attachment, or the "tip" of an organ
entire; with margins separate; basally entire; equal in size; not punctatepunctate:
surface relief—dotted with pits or with translucent, sunken glands or with colored dots, similar to pitted
dotted. Hypocotyl-radicle moderately developed, or well developed; straight; not thickened.

Distribution

General distribution: Old World.

Detailed distribution: Asia Southeastern (New Caledonia).

References

Literature specific to this family: McPherson, G., P. Morat, & J.M. Veillon. 1981. Existence d'une deuxième espèce appartenant au genre Oncotheca endémique de la Nouvelle-Calédonie et nouvelles données concernant les Oncothécacées. Bull. Mus. Natl. Nat., B, Adansonia 3:305–311.

General references: Airy Shaw, H.K. 1973. A dictionary of the flowering plants and ferns, 1,131 pp. University Press, Cambridge, Cronquist, A. 1981. An integrated system of classification of flowering plants, 1,262 p. Columbia University Press, New York, Gunn, C.R., J.H. Wiersema, C.A. Ritchie, & J.H. Kirkbride, Jr. 1992 & amendments. Families and genera of Spermatophytes recognized by the Agricultural Research Service. Techn. Bull. U.S.D.A. 1796:1–500, Mabberley, D.J. 1987. The plant-book, 706 p. Cambridge University Press, Cambridge, and Spjut, R.W. 1994. A systematic treatment of fruit types. Mem. New York Bot. Gard. 70:1–182.

 Fruit:  Oncotheca balansae ; Photo by R. Gibbons, USDA APHIS PPQ, Kirkbride et al. (2006)
Fruit: Oncotheca balansae; Photo by R. Gibbons, USDA APHIS PPQ, Kirkbride et al. (2006)
 Embryo:  Oncotheca balansae ; Illustration by K. Parker, Kirkbride et al. (2006)
Embryo: Oncotheca balansae; Illustration by K. Parker, Kirkbride et al. (2006)