Tristemon texanus Scheele, Linnaea 21: 586. 1848 (as texanum); Cucurbita pepo Linnaeus var. texana (Scheele) D. S. Decker

Pepos usually green-and-white-striped at maturity, sometimes yellow. Seeds: germination within 3–7 days.

Flowering Jun–Nov. Stream beds, lake shores, marsh banks, low woods, dunes, disturbed sandy sites; 0–100 m; Tex.

Isozyme and RAPD data indicate that var. texana is limited to south-central Texas (D. S. Decker et al. 1993, 2002b; C. W. Cowan and B. D. Smith 1993). Attribution of var. texana to New Mexico apparently has been erroneous. Plants associated with the Mississippi River drainage are var. ozarkana, according to the molecular analyses.

Molecular differentiation between var. ozarkana and var. texana suggests that reproductive isolation has allowed an accumulation of differences; H. Teppner (2004) regarded morphological variability as too overlapping to allow their unarbitrary separation. Molecular data reliably separate them and clearly delimit var. fraterna as well; morphology needs to be restudied. Fruits of var. ozarkana usually are ivory white at maturity versus striped in var. texana, but this is not completely consistent (T. C. Andres and H. B. Tukey 1995; pers. obs.).