Cockroaches 173

Figure 5.10 COCKROACHES, (a) Cinereous cockroach (Nauphaeta cinerea, Oxyhaloidae). (b) Oriental cockroach (Blatta orientalis, Blattidae). (c) Oriental cockroach egg case, (d) German cockroach egg case, (e) German Cockroach (Blatella germanica, Blatellidae). (f) Death's-head cockroach (Blaberus giganteus, Blaberidae). (g) Cuban cockroach (Panchlora nivea, Panchloridae).

Figure 5.10 COCKROACHES, (a) Cinereous cockroach (Nauphaeta cinerea, Oxyhaloidae). (b) Oriental cockroach (Blatta orientalis, Blattidae). (c) Oriental cockroach egg case, (d) German cockroach egg case, (e) German Cockroach (Blatella germanica, Blatellidae). (f) Death's-head cockroach (Blaberus giganteus, Blaberidae). (g) Cuban cockroach (Panchlora nivea, Panchloridae).

cinereous cockroach, Nauphaeta cinerea; fig. 5.10a), which derives its name from a lobster-shaped design on the head shield. It is large (BWL 25-29 mm), with well-developed, ash-colored wings that are just short of covering the abdomen in both sexes. Males stridulate when courting females. The females form oothecae with twenty-six to forty eggs that hatch as she extrudes the capsule from her brood sac.

The original home of the Oriental cockroach (Blatta orientalis; fig. 5.10b) is North Africa. Its body is shining black, except for the reddish-brown short wings of the male; these organs are mere stubs in the female. It is a medium-sized species (BWL 20—24 mm) that produces up to eighteen large oothecae (5 by 10 mm) (fig. 5.10c). The latter contain rather oversized eggs that develop free of the parent. The species is of local occurrence in dwellings but is often found outdoors where the climate is moderate.

Another very widespread vagrant cockroach is the German cockroach (Blattella germanica; fig. 5.10e). It is small (BWL 10— 15 mm) and pale buff in color, with distinct, parallel, wide bands on the head shield. Wings are nearly completely formed, only the tip of the abdomen being left exposed in both sexes. The species prefers a warm, moist ambience and is therefore common in kitchens, larders, and restaurants, rarely in bedrooms. It has the capacity to build up enormous populations when food is adequate. The oothecae are dropped free by the female and contain on the average thirty-seven eggs (fig. 5.10d). The species is considered an indoor pest, but in warm environments, heavy infestations may overflow outdoors.

References

Bell, W. J., and K. G. Adiyodi, eds. 1981. The American cockroach. Chapman Hall, London. Cornwell, P. B. 1968. The cockroach. Vol. 1. Hutchinson, London.

Giant Cockroaches

Blaberidae, Blaberinae, Blaberini, Blaberus. Spanish: Cascudas (General); cucarachas mandingas, cucarachas mama, cargatables (Peru). Cockroaches of the Divine Face, death's-head cockroaches.

Apart from being very big (the largest species, B. colosseus, reaches a BWL to 8 cm), the giant cockroaches are recognized by their fully developed, shiny, light brown fore wings, these usually marked with a large squarish spot in the middle and a diffuse spot sometimes on the outer third. There can be also an elongate thin dark bar in the shoulder area of the wing, paralleling the front margin. In addition, they have a sharply defined, square to trapezoidal black patch resting against the hind margin in the center of the oval head

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