Key to the Alabama Species of Systena
Systena frontalis (Fabricius)
Systena hudsonias (Forster)
Systena elongata (Fabricius)
Systena blanda Melsheimer*
Systena marginalis (Illiger)
Systena corni Schaeffer
Systena plicata Blatchley*

1. Elytra entirely black..... 2
    Elytra vittate or pale..... 3
2. Head entirely black..... S. hudsonias
    Frons and vertex of the head bright or dirty orange..... S. frontalis
3. Elytra vittate..... 4
    Elytra without median vittate, suture or margni may be brown..... 5
4. Prothoracic and elytra ground color black..... S. elongata
    Prothoracic and elytral ground color light brown or yellow..... S. blanda
5. Elytra lacking lateral, submarginal, longitudinal plicae..... 6
    Elytra with strong, lateral, submarginal, longitudinal plicae..... S. plicata
6. Larger (3. 7-4.7 mm. long), dirty yellow, margins of pronotum and elytra brown..... S.      marginalis
     Smaller (3.0-3.9 mm. long), entirely yellow, the suture occationally brownish..... S. corni

Systena frontalis (Fabricius)

Systena hudsonias (Forster)

Chrysomela hudsonias Forster, 1771, Nov. Spec. Ins., p. 26.
     Elongate. Entirely black except anntenal segments 3-6 brown. Head smooth, shining, occiput alutaceous. Pronotum alutaceous, finely punctate. Elytra alutaceous, closely, moderately coarsely punctate, punctures confluent. Length 3.7-4.6 mm. Width 1.4-1.9 mm.
     Alabama records: 13 specimens from DeKalb¹, Mobile¹, and Winston¹ counties.
     Seasonal distribution: April 10-June 27.
     Remarks: We have collected this species by sweeping Solidago sp. It also occurs on "Ambrosia trifida and elder" (94). In Alabama it has been collected from April 10 to June 27.

Systena elongata (Fabricius)

Galleruca elongata Fabricius, 1798, Supp. Entomol. Syst., p. 99.
     Elongate oval. Head red-brown, punctate. Antennae and legs yellow-brown but posterior femora dark brown. Pronotum shining black, closely punctate. Elytra punctate, black, each with median yellow vitta. Length 3.2-4.2 mm. Width 1.4-1.9 mm.
     Alabama records: 106 specimens from Coffee¹, Covington¹, Elmore¹, Escambia¹, Houston¹, Lee¹, Limestone¹, Macon¹, Marshall¹, Marion¹, Mobile^1,2, St. Clair¹, and Shelby¹ counties.
     Seasonal distribution: April 2-November 23.
     Remarks: This species has been collected from Ambrosia sp., Vicia sp., and Trifolium incarnatum. It also comes to light.

Systena blanda Melsheimer*

Systena blanda Melsheimer, 1847, Proc. Acad. Nat. Sci. Philadelphia 3: 164.
?Systena taeniata Say, 1824, Long's Second Exped. p. 294.
Systena ligata LeConte, 1857, Rept. Expl. and Sarv. Miss. Pacif. 13: 68 (abberation).
Systena ochracea LeConte, 1858, Proc. Acad. Nat. Sci. Philadelphia 9: 87.
     Elongate oval. Head red-brown. Pronotum shining, yellow, lateral margins brown. Elytra closely punctate; brown, more darkly so along suture, and each elytron with median yellow vitta. Prosternum and legs yellow-brown, meso and metathorax and abdomen black. Length 3.2-3.9 mm. Width 1.4-1.8 mm.
     Alabama records: 70 specimens from Clay¹, Cleburne¹, Jackson¹, Lee¹, Limestone¹, Macon¹, Madison¹, Marion¹, Marshall¹, Tallapoosa¹, and Winston¹ counties.
     Seasonal distribution: June 1-August 3.
     Remarks: This species was taken by beating Ambrosia sp. It has been collected by beating at night.

Systena marginalis (Illiger)

Haltica marginalis Illiger, 1807, Mag. Insektenk. 6: 150.
Systena oblonga LeConte, 1851, Ann. Lyc. Nat. Hist. N. Y. 5: 173.
     Elongate oval. Dirty pale yellow with lateral margins or pronotum and elytra dark brown, occasionally elytral maculation evanescent. Head shining, sparsely, finely punctate. Pronotum alutaceous, more coarsely, closely punctate. Elytra shining, densely, coarsely punctate. Length 3.7-4.7 mm. Width 1.8-1.9 mm.
     Alabama records: 84 specimens from Baldwin¹, Barbour¹, Dallas¹, Lee¹, Lowndes¹, Macon¹, Madison¹, and Mobile² counties.
     Seasonal distribution: June 1-August 1.
     Remarks: Systena marginalis feeds on a variety of plants. Auburn material has been collected from Alnus sp., Liquidambar styraciflua, and Carya illinoensis.

Systena corni Schaeffer

Systena corni Schaeffer, 1932, Bull. Brooklyn Entomol. Soc. 27: 244. New status.
     Elongate oval. Pale yellow. Head impunctate or very sparsely punctured, shining. Pronotum shining to alutaceous; shallowly to more coarsely, densely punctate. Elytra closely, coarsely punctate, shining. Pronotum and elytra unicolorous or more rarely with pronotal margins darker and elytral suture brown from scutellum to vicinity of apical declivity. Length 3.0-3.9 mm. Width 1.2-1.5 mm.
     Alabama records: 32 specimens from Baldwin¹, Houston¹, Lee¹, and Mobile^2,3 counties.
     Seasonal distribution: July 1-27.
     Remarks: This species, as far as known, feeds only on Cornis florida in Alabama. Close comparison of these beetles with specimens of S. marginalis indicated that corni, described as a variety of S. marginalis (86), should be accorded specific status. Systena marginalis is a larger, darker species which differs from S. corni by distinct features of both the aedeagi and spermathecae. Differing food plant preferences, as indicated above, further substantiate their distinctness.
     Mrs. Doris H. Blake (personal communication), USNM, who examined specimens of the suturally vittate variants of this species, asserts that these specifically differ from both S. laevis Blake and S. semivittata Jacoby by their coarse punctation. The latter 2 species, also with dark suture, are impunctate or finely punctate species from the Western United States and Mexico.

Systena plicata Blatchley*

Systena plicata Blatchley, 1921, Jour. N. Y. Entomol. Soc. 24: 26.
     Elongate, elytra subparallel. Dull pale yellow. Head and pronotum alutaceous, coarsely closely punctate. Elytra shining, not alutaceous but coarsely, closely punctate; each elytron with strong submarginal plica. Length 3.5-4.2 mm. Width 1.4-1.9 mm.
     Alabama records: 17 specimens from Houston¹ and Mobile² counties.
     Seasonal distribution: June 1-August 10.
     Remarks: This species greatly resembles S. corni but may be easily distinguished by the elytral submarginal plicae. The Houston County records were taken by the author by beating cypress (Taxodium sp.).