trimerous


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Related to trimerous: tetramerous

trimerous

[′trim·ə·rəs]
(botany)
Having parts in sets of three.
(invertebrate zoology)
In insects, having the tarsus divided or apparently divided into three segments.
References in periodicals archive ?
Lye, which can have both trimerous and dorsiventrally flattened dimerous pistils within a single spikelet (Haines & Lye, 1983; Larridon et al.
On the other hand, the sister-group relationship between Aristolochiaceae and monocots, proposed by Stevenson & Loconte (1995), among others, is supported by the presence of adaxial prophylls, trimerous flowers, monosulcate or inaperturate pollen, and sieve-element plastids of the specific type Pile.
Corolla merosity: trimerous = 0; tetramerous = 1; pentamerous = 2; hexamerous = 3; octamerous = 4.
Staminate flowers symmetrical, trimerous, not widely open at anthesis, sepals 3 short, imbricate, free, petals 3, valvate, stamens 6, slightly exceeding petals at anthesis, anthers small, dorsifixed, oval-linear with sagittate base, pistillode reduced.
Saxifragaceae, Asteraceae), or pentamerous flowers with a trimerous gynoecium (e.
Staminate flowers light yellow when fresh; sepals 3, ovate, 1 mm long, connate for 1/2 their length, lobes reaching 1/2 to the total height of the corolla tube; petals 3, ovate-acuminate, 4-7 mm long, including a 1 mm long acumen, connate up to 1-1,5 mm (1/6-1/4 of their length); stamens 12-15, 1-3 opposite each sepal and 2-3 opposite each petal, filaments 1-1,5 mm long, anther 2-2,2 mm long, round at apex; pollen elliptical, monosulcate, tectate, 25,65 [+ or -] 1,01 um diam, exine reticulate, exine thickness 0,52 [+ or -] 0,10 um, with reticule aperture 0,75 [+ or -] 0,43 um diam, reticule width 0,48 [+ or -] 0,06 um; pistillode trimerous, minute.