Mitrastemonaceae

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

Mitrastemonaceae Makino

Common name: Mitrastemon Family.

Number of genera: 1 genus.

Number of species (Mabberley 1997): 2 species.

Disseminule

Fruit (dehisced), or fruit (intact or entire), or seed.

Description

Fruits: Pistil(s) compound; 1; 1-pistillate; with carpels united. Fruit pericarpium; simple; berryberry:
an indehiscent, fleshy fruit with one or a few to many seeds. The flesh may be homogenous throughout. Or, if the outer part is hard, firm, or leathery, referred to as an hesperidium. Septa are present in some, and the seeds may be arillate or with a fleshy testa.
, or capsulecapsule:
a dry, dehiscent fruit derived from a compound ovary
; pyxidium capsulecapsule:
a dry, dehiscent fruit derived from a compound ovary
(Mitrastemon matudai Yamam.); capsulecapsule:
a dry, dehiscent fruit derived from a compound ovary
not inflated; capsulecapsule:
a dry, dehiscent fruit derived from a compound ovary
without operculumoperculum:
a dehiscent cap (or lid) of a seed or fruit that opens during germination or dehiscence
; berryberry:
an indehiscent, fleshy fruit with one or a few to many seeds. The flesh may be homogenous throughout. Or, if the outer part is hard, firm, or leathery, referred to as an hesperidium. Septa are present in some, and the seeds may be arillate or with a fleshy testa.
indehiscent; berryberry:
an indehiscent, fleshy fruit with one or a few to many seeds. The flesh may be homogenous throughout. Or, if the outer part is hard, firm, or leathery, referred to as an hesperidium. Septa are present in some, and the seeds may be arillate or with a fleshy testa.
without central placental mass; without persistent central column; not within accessory organ(s); many-seeded; many; less than 1 cm long to from 1–5 cm long; 1 cm long; with 9–15-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; not sulcatesulcate:
surface relief—having one or more elongate, relatively narrow and shallow depressions or grooves
; in transection tereteterete:
approximately circular in cross section; width and thickness approximately equal
; apexapex:
the point farthest from the point of attachment, or the "tip" of an organ
not beaked; dehiscentdehiscent:
(v. dehisce) splitting open at maturity to release contents (of a fruit)
, or indehiscentindehiscent:
not opening on its own, as in a fruit
. Dehiscentdehiscent:
(v. dehisce) splitting open at maturity to release contents (of a fruit)
unit seed(s). Dehiscentdehiscent:
(v. dehisce) splitting open at maturity to release contents (of a fruit)
regularly (but tardily); passively; linearly; by circumscissilecircumscissile:
(~pyxis); type of capsular dehiscence, opens by a lid (splitting transversely)
slit; at apexapex:
the point farthest from the point of attachment, or the "tip" of an organ
(toward apexapex:
the point farthest from the point of attachment, or the "tip" of an organ
at least); without replumreplum:
the rim, formed by the persistent placentas, and connected by a false septum in Brassicaceae fruits. The fruit valves are attached to this rim and separate from it in dehiscent fruits.
. Epicarpepicarp:
outer layer of fruit wall or pericarp, if divided into layers; note here used synonymously with exocarp
durable; glabrousglabrous:
without hairs
; without armature; smooth (apparently); 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; composed of 1 unified layer; without lactiform cavity system. Endocarpendocarp:
the inner layer of the pericarp, if divided into layers
present, or absent; not separating from exocarpexocarp:
outer layer of fruit wall or pericarp, if divided into layers; note here used synonymously with epicarp
; thin; not splitting into 1-seeded pyrenes; smooth; 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 minute; less than 1 mm long; 0.25 mm long; obovoidobovoid:
3D shape—obovate
; in transection tereteterete:
approximately circular in cross section; width and thickness approximately equal
; 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; tight; dulldull:
reflecting only a low proportion of incident light, with no apparent sheen
; surface unsmooth; surface with merged raised features; surface reticulatereticulate:
surface relief—netted, raised walls or concave grooves forming a net-like surface pattern with flat, concave, or convex interspaces
; 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; hard; not becoming mucilaginousmucilaginous:
resembling mucilage; moist and sticky
when wetted; surrounding food reserve. Endosperm copious; 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 undifferentiated from food reserve; well developed.

Distribution

General distribution: New World, Old World.

Detailed distribution: Mitrastemon matudai Middle America, Asia Major, and Asia Southeastern (Japan: Mitrastemon kanehirai).

Notes

Goldberg did not treat this family.

References

Literature specific to this family: Yamamoto, Y. 1936. Species nova Mitrastemonacearum (Rafflesiacearum) ex Mexico. Bot. Mag. (Tokyo) 50(598):539–541; Matuda, E. 1947. On the genus Mitrastemon. Bull. Torrey Bot. Club 74:133–141; Yamamoto, Y. 1925. Species nova Rafflesiacearum ex Formosa. Bot. Mag. (Tokyo) 39(461):142–145.

General references: 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:  Mitrastemon yamamotoi ; Photo by R. Gibbons, USDA APHIS PPQ, Kirkbride et al. (2006)
Fruit: Mitrastemon yamamotoi; Photo by R. Gibbons, USDA APHIS PPQ, Kirkbride et al. (2006)