Cryptocoryne loeiensis
Evergreen herb to 1,5 m tall. Subterranean stem a rhizome, to 9 × 4 cm, light brown outside and purplish white inside. Cataphylls sheathing separately petiole and peduncle, 10–20 cm long, brown; petiole to 100 × 1.5 cm, green or light dull orange with darker markings; leaf blade trifoliolate; leaflets elliptic, 20–30 × 8–12 cm, margins entire, apex acuminate, ending in an arista 1–1.5 cm long; central leaflet base cuneate, with a petiolule 3.5–6 cm long; lateral leaflets strongly asymmetrical, base convex, with a petiolule 2–3.5 cm long, glossy green with slightly impressed veins above, underside paler. Inflorescence held above the foliage; peduncle up to 1.1 m long × 5 mm across, green or purple becoming white-green towards the spathe; spathe tube subcylindrical, ca 6 × 1.5 cm at the base, widening to ca 2 cm near the mouth, pale green, paler at the base, translucent, spathe mouth margins with dark green, broad, semi-orbicular auricles, to 2 cm wide, overlapping behind; spathe limb obovate, 7–10 × ca 1.5 cm at the base, reaching ca 6 cm wide in the middle part, glossy green, apex acuminate with filiform tip to 1 cm long; spadix appendix slightly exserted from the tube, erect, subcylindrical, white-green, with a rounded, rugose apex, 2.5–4 cm long × 2–4 mm wide, sessile, often with 2 or 3 short bristles above the fertile part; fertile zone staminate or bisexual, 3.5–5 cm long; staminate flowers 2–4-androus, subsessile; anthers cream; thecae dehiscent by an oblong pore. Pistillate flowers densely arranged; ovaries ovoid; stigma on a short style, penicillate, white. Infructescence on an erect peduncle, cylindrical, to 5 × 2.5 cm; fruits bright red when ripe, ovoid, ca 6–7 mm long and wide, flattened on top, up to 4 seeds per berry. Seeds globose, 6–7 mm diam.
Chromosome number 2n = 36.
Thailand, but undoubtedly also in Laos, along the Mekong.
According to Takashige Idei who collected it first in March 2006, C. loeiensis grows on river banks that are emerged during the dry season from February to April (flowering period), in partial sun. In such places with a strong water current in the flood season, it can be found sheltered between rocks and big stones or on leeward places in the winding riverbed, and, in sheltered places, it can also be found growing in sand and gravel and more or less mud-covered. It has been found growing together with different varieties of C. crispatula.