_Trionyx spinifer asper_, dorsal views. _Top_--Left, adult male, TU 15869 (× 1/2), Escambia River, 1.2 mi. E Century, Escambia County, Florida; right, female, TU 14673.3 (× 1/2), Black Warrior River, 17-1/2 mi. SSW Tuscaloosa, Tuscaloosa County, Alabama. _Bottom_--Left, adult male, TU 17117 (× 1/4), Pearl River, Varnado, Washington Parish, Louisiana; right, female, TU 16584 (× 1/5), locality same as TU 15869.] [Illustration: PLATE 39 _Trionyx spinifer pallidus_, new subspecies, dorsal views. _Top_--Juveniles; left, TU 481 (× 2/3), Caddo Lake, Caddo Parish, Louisiana; right, KU 50832 (× 9/10), mouth of Caney Creek, 4 mi. SW Kingston, Marshall County, Oklahoma. _Bottom_--Adult males; left, holotype, TU 484 (× 1/3), locality same as TU 481; right, TU 1122 (× 2/9), Lacassine Refuge, Cameron Parish, Louisiana.] [Illustration: PLATE 40 _Trionyx spinifer pallidus_, new subspecies, dorsal views. _Top_--Females; left, TU 13213 (× 1/4), Sabine River, 8 mi. SW Negreet, Sabine Parish, Louisiana; right, TU 13266 (× 2/9), Sabine River, 8 mi. SW Merryville, Beauregard Parish, Louisiana. _Bottom_--Left, adult male, SM 2889 (× 1/4), Groveton, Trinity County, Texas; right, female, TU 14402 (× 1/5), Trinity River, near junction with Big Creek, Liberty County, Texas.] [Illustration: PLATE 41 _Trionyx spinifer guadalupensis_, new subspecies, dorsal views. _Top_--Juveniles; left, ANSP 16717 (× 1), no data; right, KU 50834 (× 1-1/10), Hondo Creek, 4 mi. W Bandera, Bandera County, Texas. _Bottom_--Adult males; left, holotype UMMZ 89926 (× 1/3), 15 mi. NE Tilden, McMullen County, Texas; right, SM 659 (× 3/10), Colorado River, near Austin, Travis County, Texas.] [Illustration: PLATE 42 _Trionyx spinifer guadalupensis_, new subspecies, dorsal views. _Top_--Adult females; left, TU 16036.1 (× 1/5), Llano River, 2 mi. W Llano, Llano County, Texas; right, TU 10160 (× 1/5), Guadalupe River, 9 mi. SE Kerrville, Kerr County, Texas. _Bottom_--Left, female, CM 3118 (× 3/4), Black Bayou, Victoria County, Texas; right, male, TU 14419.6 (× 5/9), San Saba River, 11 mi. NNW San Saba, San Saba County, Texas.] [Illustration: PLATE 43 _Trionyx spinifer emoryi_, dorsal views. _Top_--Juveniles; left, UMMZ 69411 (× 3/4), Río Conchos, 9 mi. N Linares, Nuevo León, México; right, UMMZ 69412 (× 5/6), Río Purificación, north Ciudad Victoria, Tamaulipas, México. _Bottom_--Adult males; left, topotype, TU 11561 (× 1/3), Brownsville, Cameron County, Texas; right, KU 48217 (× 1/3), Black River Village, Eddy County, New Mexico.] [Illustration: PLATE 44