Characters for Identifying Common Families of Blattodea1 (Not Including Termites)
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Characters for Identifying Common Families of Blattodea1 (not including termites) Cryptocercidae and Blaberidae have NO spines on the posteroventral margins of the middle and hind femora. These roaches do not occur in Minnesota, but are none-the- less interesting. Cryptocercidae - Brown-hooded cockroaches. Wings completely absent in adults and nymphs; sides of body nearly parallel-giving a more elongate appearance; 7th abdominal tergum and 6th sternum extend over tip of abdomen (hiding the cerci); sub- social, lives in colonies in rotting logs. The common, Cryptocercus punctulatus, along with other species in the genus, is found in the mountains of the eastern US; other species occur in the Pacific Northwest and in China. They are wingless and live communally in rotting logs, especially oak, and are able to ingest wood with the aid of symbiotic flagellates. Blaberidae - Giant cockroaches and relatives. Tip of abdomen not covered by preceding abdominal sclerites; usually with wings. Usually large species (> 15 mm or much larger) or smaller and pale green. Not sub-social, solitary These are roaches of the Deep South and tropical areas, including the Surinam roach, Pycnoscelus surinamensis, the giant cockroach, Blaberus discoidalis, and the green banana roach, Panchlora nivea. 1 Characters from Bland and Jaques (1978); photographs from Univ. Nebraska & BugGuide.net !1 Ectobiidae (=Blattellidae)2 and Blattidae have numerous spines on the posteroventral margins of the middle and hind femora. These roaches do occur in Minnesota. Ectobiidae (=Blattellidae) (in part) - Parcoblatta. Front femur with row of stout spines on posteroventral margin and with shorter and more slender spines basally (in other words, the spines are in 2 distinct size groups). This genus contains Minnesota’s only native roach, Parcoblatta pennsylvanica. It lives outdoors under bark of dead trees, especially oak, and in leaf litter in the wooded areas of the state. They are about an inch long (25 mm). The females are smaller and have short wings. They do not invade houses. Blattidae and other Ectobiidae (=Blattellidae). Spines on posteroventral margin of front femur decrease gradually in size and length toward the apex, or spines nearly equal in length. Minnesota’s species are all associated with houses. Blattidae - cockroaches. Subgenital plate divided longitudinally in female; styli of male slender, straight, and similar, subgenital plate symmetrical. Includes the Oriental cockroach and the American cockroach. 2 An ICZN Ruling (Melville, 1982) states that the name Ectobiidae is to be given precedence over Blattellidae Karny, 1908 (the replacement name for Phyllodromiidae Brunner von Wattenwyl, 1865) whenever these names are used within a single superfamily. See Zhang (2011) !2 The Oriental cockroach, Blatta orientalis is a widespread domestic species; females are brachypterous. The American cockroach, Periplaneta americana, another species found in homes, occurs in MN and on campus, including the St. Paul Student Center. Ectobiidae (=Blattellidae) (in part) - Subgenital plate not divided longitudinally in female; styli of male unequal in size and/or subgenital plate asymmetrical [NOTE: Parcoblatta has this set of genitalia characters, but can be identified most easily by the arrangement of spines on the fore femur as noted above.]. In addition to Parcoblatta, includes the German and Brown-banded cockroaches. !3 The German cockroach, Blattella germanica, is a noxious home invader that has an offensive odor when occurring in large infestations. The Brown-banded cockroach, Supella longipalpa, is another important invasive species. They once infested Hodson Hall, but have been controlled with regular applications of pesticide (insect growth regulator). !4.