1c,e,g,h); male stridulatory organ not protruding beyond the level of posterior tegminal margin; Cerci
of male much thinner than second antennal segment very slightly and gradually widened and barely flattened outer margin (Fig.
Complete reliance on this relatively covert character for identification of the taxa is unnecessary because differences in the number of sensilla (setae) on the cerci
(urogomphi) are readily discernible.
Their antennae and cerci
help them detect changes in vibrations and air pressure, making it difficult to even step on them.
Two spiked "tails," called cerci
, on the end of a roach's body, are covered with nearly 200 tiny hairs that act like antennas.
Roaches have two posterior appendages, called cerci
, covered with delicate hairs that act as mechanosensors, Davidowitz explains.
However, for this study I focused on the structure of male cerci
, both because cerci
are easy to handle and to isolate from the rest of the specimen and because the usefulness of cercal characters has already been well established by Orchelimum systematists (Rehn and Hebard 1915; Blatchley 1920; Thomas and Alexander 1962; Walker 1971).
In one of several experiments in their study of forceps (cerci
) size and symmetry in earwigs (Forficula auricularia) Radesater and Halldorsdottir (1993) placed "two male earwigs (matched for size and cerci
length but one with symmetrical, one with asymmetrical cerci
Claudio Letizia * Sabrina Cerci
Stefano Subioli Luigi Scuro Giovanni Clemente
This system uses two antennalike cerci
studded with a thousand tiny hairs to stabilize itself during flight and to detect subtle changes in air currents that enable the insect to sense encroaching predators or potential mates.
Their legs were skinnier with smaller spines, and the little stubs sticking out from the abdomen called cerci
were slightly off.
Variability among Erechthis species in the structure of the median prong of the male subgenital plate and of the cerci
is discussed in relation to their function during copulation.
The genus can be characterized by presenting occipital procces; four-segmented palpi; wings with 1-3 mm long, R5 joining C beyond the wing apex, Rs weaker than R1, but evident; variable tarsal claws (toothed or simple, and curved near basal third or beyond), empodia usually reaching to the curve of the claws or sometimes shorter; quadrate or secondarily lobed or acute male cerci
; aedeagus usually elongate and tapering to the apex or sometimes large and bulbous; ovipositor short, barely protrusible; and female cerci