dehisce

Stamens 10, the filaments not dilated basally, straight, glabrous or with short hairs; anther dehiscing by terminal pores or [+-] elongated slits, inverting just before anthesis, appendages uncommon, small, smooth, paired, at anther--filament junction, or anthers hippocrepiform, dehiscing by slits, appendages none, surfa ce usually smooth, endothecium at most poorly developed, pollen monadinous.

Stamens 10, the filaments not dilated basally, straight, smooth; anther dehiscing by slits widening considerably apically, inverting some time before anthesis, appendages long, strongly papillate, paired, at anther-filament junction, surface papillate, endothecium present, pollen monadinous.

Stamens (8-)l0, included, the filaments [+ or -] strongly dilated basally, [+ or -] straight, unicellular-pubescent or smooth; anthers tetrasporangiate, inverting only just before anthesis, slightly roughened, with a pair of dorso-apical spurs, lacking a fibrous endothecium, lacking disintegration tissue, dehiscing by terminal pores or slitlike pores.

Stamens (8-)10, included, the filaments [+ or -] straight, unicellular-pubescent or smooth; anthers inverting early in development, roughened, with a pair of dorso-apical spurs at (or just above) junction with filament, lacking a fibrous endothecium, with or without a white deposit of disintegration tissue dorsally, dehiscing by terminal, slitlike pores.

Stamens 2-15, included or sometimes exserted, the filaments straight to curved or S-shaped, distinct or connate, unicellular-pubescent or glabrous (and smooth); anthers tetrasporangiate, inverting early in development, variably roughened or smooth, with or without a pair of dorsal appendages (spurs), lacking disintegration tissue, usually lacking a fibrous endothecium, dehiscing by terminal pores or longitudinal slits.

Androecium: stamens 4-5(-12), isomerous, alternipetalous, sometimes strongly zygomorphic and adnate to corolla tube or mouth, rarely some staminodal or even obsolete (Hoppea): anthers tetrasporangiate, usually introrse (extrorse in Gentiana) and dithecal; dehiscing via a longitudinal slit or rarely by terminal pores (Exacum); occasionally connate (Voyria); occasionally connective with one to two apical glands (Sebaea); rarely with long thread-like projections (Urogentias).

Androecium: stamens isomerous, alternipetalous and adnate to corolla-tube; anthers tetrasporangiate and dithecal, dehiscing via longitudinal slits; connective forming a small apical point.

Androecium: stamens [1 (Usteria)-]4-5(-16), isomerous, alternipetalous, adnate to corolla: anthers bisporangiate or tetrasporangiate, dithecal and introrse; dehiscing via longitudinal slits; usually isostylous, occasionally heterostylous (Gelsemieae); usually free, rarely connivent (Gardneria).

Androecium: stamens (2-) 7-12 (-30) (6-30 in Theligonum), usually isomerous, alternipetalous, adnate to corolla tube or corolla mouth: filaments rarely connate (Neurocalyx) or strongly unequal: anthers tetrasporangiate, dithecal, dehiscing via longitudinal slits or rarely by pores (Argostemma); rarely connivent (Argostemma); sometimes connective produced apically.