Blaberidae

These cockroaches are ovoviviparous; they turn and retract the formed ootheca and incubate itinternally. In general, the reproductive potential of females is limited and nymphs develop slowly; some species are parthenogenetic. The legs are usually short and the femora of the front leg has one or more, short, robust spines. Many species have a hard and pitted integument and are adapted for burrowing.

Figure 4.2 Blattaria: Blaberidae. (a) Blaberus craniifer male; (b) B. craniifer nymph; (c) B. discoidalis male; (d) B.giganteus male.

Death's-head cockroach, Blaberus craniifer (Fig. 4.2a, b) Adult males are 43-50 mm long and females are 55-60 mm long; the body is brown to blackish brown. Wings extend by about one-third beyond the tip of the abdomen; front wings are dark brown to blackish brown, except for a pale brown region adjacent to the pronotum. The pronotum is large and has a wide, pale brown margin; the center is dark brown with yellowish-brown markings. Femora 1 has robust spines on the ventral margin; femora 2 and 3 have spines on the ventral margin. Pronotum markings and cuticle formation somewhat resemble human eyes, nose, and mouth. This feature is the origin of the common name. Nymphs have a large pronotum; yellowish orange spots are on the pronotum, thorax, and abdominal ter-gites. The ootheca is about 20 mm long and lightly sclerotized; it is pale brown to light brown and indentations show the position of the eggs; a distinct keel is absent. The ootheca contains about 34 eggs, and when formed it is retracted into the brood chamber. Developmentis completed in 257-277 days at 30-36 °C and there are 9-11 instars. Adults live 420-480 days. Natural habitats include ground vegetation and under rotting logs in wet forested areas, and in caves; they feed on plant material. In the urban environment, they occur in restaurants, food stores, and in houses. B. craniifer secretes an aggregation pheromone from mandibular glands, and this may promote large infestations in favorable harborages. This species occurs in the American tropics. It is established in southern Florida, where it occurs in firewood piles, refuse, and around buildings. This species is a household pest in Santiago, Chile and Havana, Cuba; it occurs in Mexico, Belize, and Dominican Republic. Adults are attracted to lights at night in Brazil.

During courtship the male of B. craniifer stands near a female and slightly raises his abdomen on his legs and makes trembling movements with the abdomen. Sometimes the male butts the female with his head or pronotum. The male moves his abdomen under the female, so that the female straddles the male abdomen. Once the male genitalia connect with the females, the pair move in opposite directions. They remain joined for about 4 h.

Other Blaberus There are several species that occur in the urban or agricultural environments. In the natural environment, B. discoidalis (Fig. 4.2c) has been taken under bark of a dead tree; in the urban environment it occurs in restaurants and food stores in Ecuador, in houses in West Indies and Puerto Rico. It is distributed throughout Central America. This species is also known from Cuba and Jamaica, and may be established in the USA, in Key West, Florida. B. giganteus (Fig. 4.2d) adults are 70-80 mm long; the front wings are pale brown and nearly translucent. Nymph development is 140-200 days at30 °C and 60% relative humidity (RH); adults live as long as 600 days. B. atropos is native to South America, and has the death's-head markings on the mesonotum and metanotum; along with B. boliviensis it has been found associated with bananas.

Calolampra irrorata Adult males are about 24 mm long and speckled brown; the head is not completely concealed by the pronotum; the mid and hind femora have spines. The wings extend beyond the tip of the abdomen. The female is about 20 mm long and 15 mm wide, and wingless. The females are usually in soil, but the males are active flyers, and are attracted to lights at night. This species occurs in Australia, and it was first collected in 1770 during Cook's first voyage to Australia.

Hissing cockroach, Gromphadorina laevigata Adults are about 6 cm long and the body is covered with scaly granulations. Males and females are wingless and somewhat slow-

moving. Males are distinguished by a large round tubercle on each side of the pronotum, and a pair of styles at the end of the abdomen. The thoracic tubercles are used to batter other males as a part of courtship behavior. Adults and nymphs have strong spines on their legs. Disturbed adults and nymphs or males encountering other males make a hissing sound. This is produced when air is forcibly squeezed out of the spiracles on abdominal segment 2. Hissing sounds may also serve to attract females. The ootheca is 30-32 mm long and contains 32-48 eggs. The female produces an ootheca in 2-3 h, after which it extends about 25 mm from the tip of her abdomen. Then it is slowly drawn back into the internal brood sac, which is large and extends into the metathorax. Eggs are incubated internally for about 70 days, and nymphs hatch and exit the female's body over a period of about 2 days. Newly emerged nymphs usually remain grouped around and under the female for a short period. Natural habitats for this cockroach include wet or moist leaf litter; it is not known to be a household pest. This species is native to Madagascar.

Madagascan hissing cockroach, Gromphadorina portentosa

Adults are about 10 cm long and blackish brown. Males and females are wingless. Similar to G. laevigata, when disturbed the adults and nymphs make a hissing sound. This is produced when air is forcibly squeezed out of the spiracles on abdominal segment 2. This species provides a form of maternal provisioning of newly hatched nymphs. Shortly after expelling the hatching ootheca, the female exudes from her abdominal tip a pale white substance. The newly hatched nymphs actively feed on this material. Integumentary gland cells lining the brood sac are the most likely source of the secretion. This species is sometimes sold commercially as a household pet. This species is native to Madagascar.

Other Gromphadorina This genus is native to Madagascar, and species are not known to occur naturally outside this location. Several species are used for physiological research and various educational exhibits and demonstrations, including G. coguereliana, and G. portentosa.

Lobster cockroach, Nauphoeta cinerea (Fig. 4.3a, b) Adults are 25-29 mm long and light gray. Wings are mottled or speckled, and do not cover the abdomen. The pronotum is pale brown and has irregular brown markings and a submarginal black band on each side; the posterior margin is rounded. The pronotum usually has a lobster-like color pattern, which is the origin of its common name. Nymphs have pale markings on

Figure 4.3 Blattaria: Blaberidae. (a) Nauphoeta cinera female; (b) N. cinera nymph; (c) Rhyparobia maderae male; (d) R. maderae nymph.

the anterolateral margins of the abdominal tergites. The ootheca is 15-18 mm long, pale brown and curved; there are distinct indentations showing the position of the eggs. The ootheca contains 26-40 eggs and itis carried internally 36 days until the eggs hatch; fecundity is 1-6 broods. Nymphs hatch as the female extrudes the ootheca from the brood sac; they shed their embryonic membrane as they hatch, and eat both it and the ootheca. In the laboratory, the number of nymphs hatching increases from about 20 for the first eggcase to about 30 from the third, and then decreases. Newly hatched nymphs usually crawl beneath the female and remain there for about 1 h after hatching. Nymph development in isolation in the laboratory at 30-36 °C includes seven instars and takes about 73 days for males, and eight instars and about 94 days for females. Developmentin groups of nymphs takes about 72 days for males and about 85 days for females. Adult life span is about 344 days for females and about365 days for males. The interval between the molt to adult and the production of the first ootheca is about 13 days. Males stridulate when courting nonreceptive females. The sound is produced by ridges laterally on the hind margin of the pronotum, which move against the costal vein at the base of the wings.

Natural habitats for this species are outdoor sites where it feeds on plant and animal materials. It is known to kill and eat individuals of the Cypress cockroach, Diploptera punctata. In the urban environment, it lives primarily around the outside of buildings, but occurs in houses and hospitals in Australia, and household huts in Sudan. Infesting populations occur in mills processing animal feeds, and in feed-storage rooms of commercial poultry operations. This species seems to prefer food containingfish oil. Itis occasionally introduced into temperate regions with food materials and has been recorded in the UK and Germany inheated buildings. N. cinerea is probably native to East Africa, below the equator. Itlikely spread to other regions through trading ships and commerce. It was introduced into Brazil from Africa, and into Mexico from the Philippines. Current distribution is tropical regions of the world, including South America (Brazil), Cuba, WestIndies, Mexico, Galapagos Islands, Hawaii, Australia, Philippines, Indonesia, Malaysia, Singapore, Mauritius, and Madagascar. Itis established in the USA, around Tampa, Florida.

Cuban cockroach, banana cockroach, green cockroach, Pan-chlora nivea (Fig. 4.4e, f) Adults are 15-20 mm long. The body is somewhat flattened, and light or pale green to yellowish green (specimens in alcohol do not show the pale green color); integument is slightly translucent. Cerci are short and blunt, and the supraanal plate (epiproct) is distinctly bilobed. Wings extend beyond the abdomen in both sexes; cerci are short and broad. Nymphs are pale brown and somewhat flattened. The ootheca is 3-4 mm long and curved; it has indentations showing the position of the eggs. The ootheca contains about 46 eggs, and it is carried internally in the female until the eggs hatch in about 48 days at 24 ° C. The interval between the oothe-cae production is about 63 days. Developmentin the laboratory at 24 °C takes about 144 days for males and about 181 days for females. Females live about 153 days at 24 °C. Courtship behavior is limited: the male moves his body sideways for several minutes, moves behind and backs up to the female to engage her genitalia, and then transfers a spermatophore.

Natural habitats include under the rotting bark ofpalm and coconut trees, and in moist shaded areas with abundant leaf litter; it is commonly found with bananas. In the urban environment, it occurs in peridomestic habitats, and itis attracted to lights indoors and outdoors. It does not infest structures. This species has been introduced to various parts ofthe world with shipments of bananas and other fruits. It is distributed in the western hemisphere tropics, and has been recorded

Figure 4.4 Blattaria: Blaberidae. (a) Pycnoscelus indicus male; (b) P. indicus female; (c) P. surinamensis nymph; (d) P. surinamensis male; (e) Panchlora nivea male, posteriorabdominal segments and supraanal plate; (f) P. nivea male.

from Mexico, Cuba, Puerto Rico, Trinidad, Greater Antilles, and Bahamas. It is widely distributed in Central America and northern South America. It is established along the Gulf Coast of the USA, from Texas to Florida.

Panchlora irrorata Adult males are about 14 mm long and females are about 20 mm long. The body is flattened and light green to yellowish green; the integument is slightly translucent. The species name means sprinkled with dew, and probably refers to the integument. Wings extend beyond the abdomen in both sexes; antennae are notlonger than the body. Last-instar nymphs are about 15 mm long and brown. The ootheca is 3-4 mm long, thin-walled and colorless; it is carried internally until the eggs hatch. The ootheca contains about 12-48 eggs, the number of undeveloped eggs ranges from 1-24;

hatching occurs in about 63 days. Development in the laboratory takes about 196 days for males and about 207 days for females; adultmales live aboutio8 days and females for about 130 days. Male courting behavior begins with rocking his body sideways; he then moves behind the female. When the male and female are in a linear position, end to end, he moves backwards, towards the female to make genital contact. Copulation lasts 20-25 min. This species is distributed in the Central American tropics, but it is carried to other regions on shipments of bananas or other fruits.

Surinam cockroach, Pycnoscelus surinamensis (Fig. 4.4c, d)

Adults are 18-25 mm long. The body is dark and shiny brown to blackish brown. The pronotum is blackish brown, except for the anterior margin, which is pale brown. Wings are light brown, which gives the insect a bicolored appearance. Wings extend to the tip of the abdomen in both sexes; antennae are about one-third the length of the body. Thorax and abdominal segments i-3 are glossy, but the dorsum of the terminal abdominal segments is dull and granulated. Nymphs are

Figure 4.4 Blattaria: Blaberidae. (a) Pycnoscelus indicus male; (b) P. indicus female; (c) P. surinamensis nymph; (d) P. surinamensis male; (e) Panchlora nivea male, posteriorabdominal segments and supraanal plate; (f) P. nivea male.

uniformly dark brown. The ootheca is 12-15 mm long and pale yellow to pale brown and membranous; it lacks a distinct keel and it is slightly curved; there are indentations showing the position of the eggs. The ootheca contains 14-48 eggs and it is carried internally until the eggs hatch in about 35 days at 18-34 °C; fecundity is 1-5 oothecae. Nymphs hatch as the female extrudes the ootheca from the brood sac. Development is through 8-10 instars and lasts 127-184 days at 18-24 °C. Adultfemales live about307 days. In parthenogenetic populations, the first ootheca is formed about 7 days after the final molt. There are parthenogenetic and bisexual regional populations of P. surinamensis. Males are not known to occur in populations in the UK, continental Europe, and mainland USA. However, Hawaiian and some Asianpopulations are apparently bisexual.

In natural habitats adults and nymphs occur under stones, and all stages burrow in loose litter and in the top layer of soil; they occur in nests ofwood rats in Texas. They feed on plants and cause economic damage to potato tubers in Haiti, pineapple roots in Hawaii, and tobacco plants in Sumatra. In the urban environment, this cockroach is common around buildings in warm climates. It occurs in greenhouses in parts of the USA, where it cannot live outdoors; it is occasionally found around potted plants in shopping malls, hotel lobbies, and similar locations. Adults and nymphs penetrate and find harborage in loose soil to a depth of 8-10 cm. P. surinamensis can be carried in nursery stock and house plants to regions outside its normal range. This species is probably native to the islands of the Malay Archipelago, now it is widely distributed in tropical and temperate regions. It is known from England, Scotland, and Germany; in North America it occurs in Texas, Florida, Louisiana, and South Carolina. It is established in Hawaii, and there is an isolated population in an urban area near Palm Springs, California. Bisexual populations are sometimes designated as P. indicus (Fig. 4.4a, b).

Madeira cockroach, Rhyparobia maderae (= Leucophaea) (Fig. 4.3c, d) Adults are 40-50 mm long and pale brown to light green, and slightly mottled. The posterior two-thirds of the front wings have a fishnet appearance. Wings cover the abdomen and there are two dark brown, curved lines at the base of the front wings. The pronotum and front wing margins are translucent. The male has a specialized organ on abdominal segment 2. Femur 1 lacks strong spines on the ventral margin, only a row of fine setae. Adults are slow-moving but readily fly; they emit an offensive odor. Adults stridulate by moving the posterior margin of the pronotum over the mesonotum. Nymphs have short spines along the dorsal posterior margin of each segment. Oothecae are 16-19 mm long, yellowish brown, and there are slight indentations showing the position of the eggs. The ootheca contains about 34 eggs and it is carried internally for 58-60 days. Nymph development in isolation in the laboratory at 30-36 °C includes seven instars and takes abouti27 days for males, and eightinstars and abouti63 days for females. Development in groups of nymphs is complete in about 121 days for males, and about 150 days for females. Adult life span may be 2.5 years. Courtship begins with the male moving next to the female and rapidly moving his body up and down. In some instances the male raises the anterior portion of his body and strikes his abdomen against the substrate to produce a tapping sound. Adults mate i0-i4 days after maturation, and the first ootheca appears in about 20 days.

In natural habitats in tropical regions this species occurs in large populations and feeds on plant material, including fruits such as banana and grapes. Banana is apparently a favorite food, and R. maderae is transported to other regions with shipments of this fruit. In the urban environment, it occurs indoors in Madeira, Windward Islands, Philippines, and Trinidad; in Puerto Rico, it is found in fruit stores, warehouses, and food markets. It is established in some heated buildings in New York City. It was probably introduced accidentally in household materials carried by immigrants from Puerto Rico. This species was first described from the island ofMadeira, which is the origin of its common name. It is probably native to West Africa, south of the Sahara, where there are several other species of this genus. Current distribution of this species is most of the tropical regions of the world. This species occurs along the western coast of Africa, and it is established in Morocco, Spain, and Corsica. It is established in West Indies, Cuba, Jamaica, Puerto Rico, and Greater and Lesser Antilles. In South America, it occurs in coastal Brazil. It is known from Philippines, Indonesia, and Hawaii.

Other Blaberidae Most of the species in this family are minor pests and occur only occasionally indoors. Epilampyra maya has been reported from aquatic and moist habitats in Central America, and it occurs in and around houses in Acadia, Florida. Phoetalia pallida is widely distributed in the tropics, and it occurs in and around structures in the West Indies and the USA (Florida).

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