17. Tyloderma myriophylli Wibmer, new species Holotype male.-Body oval, moderately convex; cuticle brownish red, with elytra light brownish red. Rostrum with longitudinal carina, continuous on frons toward vertex; punctures small, moderately shallow, very dense on basal 2/5, unevenly sparser on apical 3/5. Head with punctures small, moderately shallow, very dense. Prothorax (fig. 17) ca. as long as wide, weakly constricted on flanks, not constricted dorsally near apex, Sides subparallel in basal 3/5, then converging moderately toward apex; pronotal disc with punctures very small, moderately shallow, unevenly moderately dense; medium sized, moderately deep, dense along sides of pronotum and on flanks (fig. 30), with large, more or less triangular dorsal area of flank scarcely punctate from base to near middle. elytra (fig. 17) 1.47 times as long as wide, 2.22 times as long as prothorax, humeri moderately obtuse, moderately prominent, sides subparallel in ca. basal 3/5, then converging toward apex; strial punctures on disc small, moderately deep.'" ca. 3 times as large as pronotal punctures, unevenly distributed, generally separated by more than their own diameters, on lateral striae deeper, more even and denser; smaller and shallower toward apex, nearly obsolete on apical l/4; strial grooves nearly obsolete, apical l/2 of 8 moderately distinct, apical 2/3 of 9 very distinct; intervals not raised at apex. Mesostemum with surface weakly convex, punctures medium sized, moderately deep, dense; mesepistemum and mesepimeron densely punctate. Metastemum nearly fiat on median area, with broad, longitudinal, impunctate median band on posterior 1/2; punctures medium to large, moderately deep to deep and dense on median area, shallower on lateral areas. Abdomen with sternum 1 concave on basal 4/5, remainder of venter weakly convex; punctures very small, shallow, moderately sparse on sterna 1 to 4, small, moderately shallow, moderately dense (denser toward apex) on sternum 5. Legs with coxa, basal 1/2 and inner surface of femur, and inner surface of tibia light brownish red, remainder blackish; femur with inner margin weakly rounded, surface strongly rugosely striate; tibia with inner margin strongly sinuate, surface moderately rugosely striate. Genitalia: fig. 84. Length (pronotum + elytra): 3.30 mm. (1.025 + 2.275). Allotype female.-Abdominal sterna 1 &. 2 convex. Genitalia: fig. 117. Length (pronotum + elytra): 3.90 mm. (1.15 + 2.75). Intraspecific variation.-The rostrum is 1.58-1.78 times as long as its width at the apex; the carina may be scarcely distinct on the frons and/or on the rostrum, and sometimes ends dorsally in a small, shallow pit. The prothorax has a ratio (length/width) of 0.95-1.05 48 (1.01 ± 0.03), with its sides subparallel in the basal 1/2 to 3/5. The elytra are 1.33-1.53 (1.44 ± 0.04) times as long as wide, and 2.00-2.37 (2.15 ± 0.09) times as long as the prothorax, widest between 1/6 from the base and the middle. Sometimes there are a few punctures at the apex of stria 2. The posterior area of the metasternum may be sparsely punctate; and the base of sternum 1 may be rugosely striate between the metacoxae. Length, pronotum + elytra: 2.95-3.90 mm. (3.45 ± 0.22). Remarks and comparative notes.-As indicated in the key, this species is very distinct from all the other species known in the genus. Etymology.-8pecies named for its probable host plant genus, Myriophyllum. Type-locality.-U.S.A., Florida, Leon County, Tall Timbers Research Station, Bird Window.