Blattidae

These cockroaches carry the ootheca upright and without turning after it is formed. Species in this family are characterized by the presence of spines on the anterior margin of the front femur; the mid and hind femora have spines on the anterior and posterior margin. Sternum 7 of the female is large; its posterior edge is modified to form two lobes or valves, and these lobes are partly separated from the remainder of the sternum by a transverse suture. Tergum 10 of both sexes is rectangular, rounded, or triangular; the cerci are often short and flattened.

Turkestan cockroach, Blatta lateralis (= Blatta tartara, Shelfordella tartara) (Fig. 4.1a; 4.7b, c) Adult males are i9-23 mm long and females are 22-25 mm long. The male is light brown to yellowish brown; the pronotum is reddish brown centrally, and has wide margins of transparent yellow.

Male supraanal plate (epiproct) has the apex broadly notched. Wings extend beyond the abdomen; the outer margins of the wings are pale yellow. Female is blackish brown to black and brachypterous. Pronotum has pale yellow wing stripes and scattered yellow markings. The front wings of the female are separated by a distance less than the width of the wing. Both sexes are capable of flying. Large nymphs have the anterior half of the body yellowish red; the posterior halfis dark brown. The ootheca is 9-12 mm long, brown to blackish brown, rounded at one end, and dorsally truncated at the other end. Nymphs develop in 118-137 days at 30-35 °C. Adults live about 1 year. Natural populations of this species occur in desert regions in North Africa, from Libya eastward to Asia. In the urban environment, it occurs around the outside of buildings and in underground pipes of sewer systems. It is distributed in Egypt, Saudi Arabia, the Sudan, Israel, and Iran, Iraq, and Afghanistan. It may have been introduced to the USA on military equipment from the Middle East. It is known to occur indoors and outdoors in Texas, and other sites in southwestern USA.

Oriental cockroach, waterbug, Blatta orientalis (Fig. 4.1b; 4.7a) Adultmales are 17.5-28.7 mm long and females are 2027 mm long. The body is shiny, and reddish brown to blackish brown. Wings of the male cover two-thirds of the abdomen, while female wings extend slightly past the thorax; neither sex is capable of flying. Tarsi of adult females and nymphs have a reduced arolium. Without this cushion-like pad between the claws, they have difficulty climbing smooth surfaces. The arolium is of variable size in adult males. Nymphs are reddish brown; first-instar nymphs are about 6 mm long and pale brown. The ootheca is 10-12 mm long and blackish brown; egg compartments are not distinct. The ootheca contains 16-18 eggs, and hatching occurs in 42 days at 29.5 °C and 81 days at 21 °C. Females do not produce oothecae in environments where the temperature is 15 °C or below. Oothecae lose viability when exposed to temperatures of 0 °C or below. Oothecae are produced at intervals of 1-2 weeks; fecundity is 6-8 oothecae. Females carry the ootheca for about 30 h after it is formed. Then it is deposited or attached to the substrate in a protected location. Nymph development is through 7-10 instars; at 22 °C it takes 515 days for males and 542 days for females; at 28 °C it is 288 days for males and 310 days for females; and at 30 °C it is 164 days for males and 282 days for females. Females live 35-190 days, males 112-160 days. Adults appear in May or June, and die in July or August. Parthenogenesis occurs, and some of the eggs in these oothecae develop

Figure 4.7 Blattaria: Blattidae. (a) Blatta orientalis male; (b) B. lateralis adult, pronotum and elytra portion; (c) B. lateralis male, supraanal plate.

and hatch; the resulting nymphs are females. A small number of these nymphs reach maturity. Survival without food or water at 27 °C is about 11 days for males and 13 days for females; survival with water is 20 days for males and 32 days for females.

During courtship the male moves around the female with his abdomen extended. When the male is in front of the female, he backs under her. As the female's head advances along the male's abdomen, he raises and expands both pairs of wings, and the female's mouthparts contact the male's abdominal segments. Then he continues to extend his abdomen under the female and brings his genitalia to contact hers, and ifsuc-cessful, he turns from under the female and the joined pair face in opposite directions. The mating process lasts about ih. Whenthe ootheca first emerges from the tip of the female's abdomen it is yellowish white, and then turns reddish brown. It is not turned and the keel remains upright. Formation of the ootheca is completed in 24 h, and it is carried usually i-2 days, and up to 7 days before it is deposited. It is placed in a sheltered place or the female attaches it to a substrate with an oral secretion. Oothecae may be partially or completely covered with small particles of debris from the substrate.

Natural habitats for this species probably include leaf litter and debris in areas with warm summer temperatures and a moderate winter. Natural populations occur on the Crimean Peninsula and in the region around the Black Sea and Caspian Sea. In the urban environment, it occurs indoors and outdoors. Large populations are typically in basements, cellars, crawl spaces, and in underground sewer pipes, and urban landfills. An aggregation pheromone in the feces promotes large populations and crowding in suitable harborages, and probably reduces the movement of adults and large nymphs. The association with cool and damp basements is probably the origin of the common name, waterbug. The preferred temperature range for B. orientalis is 20-29 °C, and this species is most common in north temperate regions, and less in tropical regions. Adults and large nymphs are active in early spring when daytime temperatures are 10-15 °C. Activity and pest status of this cockroach usually peak in the spring, typically from May to early July, when adults and nymphs move indoors.

Gisborne cockroach, Cutilia semivitta (= Drymaplanta)

Adults are about40 mm long and 12 mm wide; they are wingless and somewhat flattened. Body is shiny, dark reddish brown to black and with a pale yellow to white band on the sides of the thorax. Nymphs are light brown dorsally and yellowish brown ventrally. This species lives outdoors in cracks and crevices in rotting wood in natural areas; in the urban environment it is found in and around poultry houses, dog kennels, and under debris around buildings. It was introduced to New Zealand from Australia, and first found in Gisborne. It is now spread over the North Island and in environs ofNelson, South Island. It may occur indoors during winter months.

Stinking cockroach, Florida wood cockroach, Eurycotis flori-dana Adults are 30-40 mm long. The body is dark brown to blackish brown; recently molted individuals are reddish brown. Front wings extend slightly past the mesonotum, while hind wings are absent; the adults do not fly. The first segment of the hind tarsus is shorter than segments 2-5 combined, and the pulvilli of segments 2 and 3 are large. The male has short cerci and the supraanal plate (epiproct) is slightly notched. Medium and large nymphs have yellow margins on the meso-and metathorax. Adults mate about 18 days after maturation, and the first ootheca appears in about 55 days. The ootheca is 14-16 mm long, dark brown, and has distinct indentations that show the position of the eggs. The ootheca contains 21-23 eggs, and oothecae are produced inabout8-day intervals; hatching occurs in about 50 days at 30-36 °C. In natural habitats, oothecae are often buried in the soil or in decaying logs. Parthenogenesis occurs in this species, but the nymphs do not develop to adults. Nymph development is 286-302 days at 27 °C. Adults, but not the nymphs, emit an extremely foul odorous secretion when disturbed. This secretion is produced by glandular cells and stored as a yellow liquid in a bilobed sac; it is ejected through a pore in the sternal, intersegmental membrane of abdominal segments 6 and 7. A liquid spray can be ejected 2-3 cm to about 1 m. The spray irritates the eyes of humans, and it is toxic to the cockroach if it is confined in a small container.

During courtship the wingless male stands near the female and repeatedly moves his body from side to side. While doing this, he extends his abdomen slightly to expose the intersegmental membrane between abdominal segments 6 and 7. The female applies her mouthparts to the male's dorsum starting near the end of the abdomen, and progressing up to abdominal segment 1, on which is located a small glandular area bearing a patch of setae. While the female is palpating the glandular area, the male couples his genitalia with hers.

Natural habitats for this species include the cavities under the bark and the decaying holes in dead trees, stumps, and woodpiles, and sometimes in leaf litter. In the urban environment, it occasionally enters buildings, but it does not become established indoors. Eurycotus species occur in WestIndies and tropical regions of Central and South America. E.floridana is recorded from USA, specifically Florida, Georgia, Alabama, and Mississippi.

Vagabond cockroach, Pelmatosilpha larifuga Adults are 28-31 mm long and they are dark reddish brown to black. Lateral margins of the pronotum and the front wings have a pale yellow band. Both sexes are brachypterous and have the posterior margins ofthe abdomen exposed behind the wings. Species in this genus occur in Central and South America, and the WestIndies. Adults and nymphs ofP.larijUga areoftenfound on bananas shipped from West Indies to other regions of the world, and they occur in warehouses and food stores.

American cockroach, Periplaneta americana (Fig. 4.1c; 4.8a, f)

Adult males are 34-53 mm long and female are 29-36 mm long. The body is shiny, reddish brown to brown; pronotum has a yellowish white margin with dark brown interior. Wings extend 4-8 mm beyond the abdomen in males, and as long as the abdomen in females. Adults readily fly when the temperature is above 21 °C; they usually travel short distances, but sustained flight is possible and they fly to lights at night. The male has a pair of styli and a pair of cerci at the end of the abdomen. Cerci are 18- or 19-segmented, and tapered at the tip. The male supraanal plate (epiproct) is translucent, apically rounded and deeply notched. Females lack styli, and their cerci are 13- or 14-segmented. The first-instar nymph is uniformly pale brown, and the tips of the maxillary and labial palps are white; antennae are as long as the body and pale brown. Wing pads develop during the third- or fourth-instar nymph, and the sixth-instar nymph has pale brown patches on the pronotum; wing pads on the last nymph instar are about 7 mm long. The sex of the early

Figure 4.8 Blattaria: Blattidae. (a) Periplaneta americana male; (b) P. australasiae adult, pronotum and elytra portion; (c) P. brunnea adult, pronotum and elytra portion; (d) P. australasiae male, supraanal plate; (e) P. brunnea male, supraanal plate; (f) P. americana male, supraanal plate; (g) P. fuliginosa male, pronotum and elytra portion; (h) P.japónica male; (i) P. fuliginosa male, supraanal plate.

Figure 4.8 Blattaria: Blattidae. (a) Periplaneta americana male; (b) P. australasiae adult, pronotum and elytra portion; (c) P. brunnea adult, pronotum and elytra portion; (d) P. australasiae male, supraanal plate; (e) P. brunnea male, supraanal plate; (f) P. americana male, supraanal plate; (g) P. fuliginosa male, pronotum and elytra portion; (h) P.japónica male; (i) P. fuliginosa male, supraanal plate.

instar nymphs can be distinguished by the posterior margin of sternite 9: it has a median notch in the female and it is only slightly indented in the male.

The ootheca is 8-10 mm long, dark brown to blackish brown; egg compartments are indistinct; there are 16 teeth on the keel. The ootheca contains 14-16 eggs. Hatching occurs in 57 days at24 °C, 32 days at30 °C, and 24-38 days at30-36 °C. Females carry the ootheca for about 24 h, but it may be retained for up to 6 days before being deposited. Fecundity is 15-90 oothecae, typically 10-15 within 10 months; the interval between oothecae formation is 5-12 days. The ootheca may be cemented to the substrate by an oral secretion from the female; sometimes they are partially covered by pieces of debris from the substrate.

Females often eat other P. americana oothecae that are encountered in the habitat. Parthenogenesis occurs but is infrequent. About 50% of the parthenogenetic nymphs hatch, and only 33% of those that hatch reach maturity. Nymph development is 7-13 instars during 5-15 months at 25-30 °C. Variations in development occur among cockroaches hatched from the same ootheca. First-instar nymphs consume their embryonic skin immediately after hatching, and the cast skin is usually eaten by other stages except the last. Preferred temperature for adults and nymphs is about 28 °C, but they remain active at 21 °C. Adult life span at 29 °C is 90-706 days for females, and 90-362 days for males. Survival without food or water at 27 °C is about 29 days for males and 42 days for females; survival with water is 43 days for males and 90 days for females.

During courtship, the male and female employ volatile pheromones and tactile stimulation to achieve copulation. It may begin with the female releasing a volatile sex pheromone, which is composed of the sesquiterpenoids, periplanone A and B. This pheromone is detected by the male antennae and directs him toward the female. The female assumes a stance with the abdomen slightly lowered and with the abdominal terga 8 and 9 spread so that the underlying tissues are exposed. When close to the female the male usually waves and contacts the female with his antennae, and raises his wings. The male then turns around and flutters his wings, and moves backwards. He pushes his abdomen under her. If the male succeeds in engaging his genitalia, he turns from under her or the female turns so that the pair is in an opposed position. They remain joined for i h or more while the male transfers a spermatophore to the female. The ootheca is not turned after it is formed and the keel remains upright. Fresh mating is not necessary for the production of each ootheca, and females can produce nearly their full potential ofootheca from a single mating.

Natural habitats include generally moist areas in leaf litter, under bark or the bracts ofpalm trees in forested or undisturbed areas with dense vegetation, but also including caves and burrows. Feral populations of this species in its native region of tropical Africa may not exist. The genus Periplaneta includes 47 described species, but none are endemic to the Americas. The specific name P. americana is misleading because of the African origin of this species. P. americana probably spread by trading and slave ships, and commerce to many regions of the world by the time it was described by Linnaeus in 1758. Evidence of this species was recovered from a Spanish ship sunk off the coast of Bermuda in 1625. Most Periplaneta species have restricted distribution and they are not closely associated with humans. Worldwide distribution and pest status characterize only the few species that are capable of adapting to domestic or peridomestic habitats.

In the urban environment, P. americana occurs outdoors and indoors in a wide range of habitats, from urban landfills and wastewater treatment plants to the underground sewer systems of the major cities of the world. Large populations of P. americana can develop in favorable habitats, such as in the holds of ships, and urban landfills. A feces-secreted aggregation pheromone, which operates during the day when individuals are inactive, promotes concentrations of adults and nymphs. Crowding and limited food may cause mass migrations of adults and nymphs from preferred habitats. Indoors, this species is common in basements and cellars, as well as on upper floors oflarge buildings. Itis a successful and sometimes dominant species in urban environments around the world, from tropical to temperate climates.

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