Giant Jawed Sawyers

Cerambycidae, Prioninae, Ancistrotini, Macrodontia. French: Mouches scieur de long, mouches cafe (Guadeloupe). Sawyer beetles.

Six species make up this genus of unique, large longhorns, but only three are at all well known. Macrodontia ceruicornis (fig-

Figure 9.13 LONG-HORNED BEETLES (CERAMBYCIDAE). (a) Giant jawed sawyer (Macro-dontia cervicornis). (b) Big jawed sawyer (Macrodontia dejeani). (c) Bearded imperious sawyer (Callipogon barbatum), male, (d) Giant imperious sawyer (Callipogon armillatum), male.

9.13a) is the largest (BL to 15 cm) and is more widespread than M. flavipennis or dejeani (fig- 9.13b) (BL of both reaching only 9 cm). It has a brown and black patterned prothorax, head, legs, and jaws and very irregular, dark longitudinal ely-tral markings. The latter two species, of local occurrence in the Caribbean and South America, are solid purplish-black anteriorly and with dark legs and elytra striped with neat lines. All have similar enormous, incurved mandibles with uniform internal teeth, one of which is enlarged just beyond half the length; Macrodontia tend to be somewhat flattened and wide also, in contrast to most other more cylindrical cerambycids.

Because of their serrate jaws, they are among those beetles erroneously thought to sever twigs (serradores). They allegedly clasp the branches of the coffee plant, for instance, with the mandibles and then gyrate around until the limb is cut through. And they are said to produce a characteristic buzzing sound when doing so (Duffy 1960: 53). Only fragmentary information is available regarding the biology of these giants (Bondar 1926). The adults are nocturnal and sometimes come to artificial lights where they are often captured for sale to collectors, by whom they are in great demand.

The larvae, which are likewise very large (up to 21 cm in M. cervicornis), create extensive galleries more than a meter long and 10 centimeters wide in the hearts of dead and dying softwood trees, such as the coconut palm (Cocos), Attalea, and Ceiba pentandra. The Ungurahui palm (Jessenia weberbauri) is a host in Peru (Paprzycki 1942). Hosts of M. dejeani alone are Acrocomia and Acacia decurrens (Duffy 1960: 51-54).

Morphologically, the larvae are unique among the family in having the thoracic and abdominal segments densely velured and the integument brown instead of white as is usual. In Brazil, they are avidly sought by the natives for food (Netolitzky 1920).

Another large species in the same tribe is Ancistrotus cummingi, known in Chile as madre de la culebra (mother of snakes), probably from the elongate form of its larva.

References

Bondar, G. 1926. A biología e a larva do bezouro Macrodontia cervicornis. Chacaras e Quintaes (Säo Paulo) 34: 33-35. Duffy, E. A. J. 1960. A monograph of the immature stages of the Neotropical timber beetles (Cerambycidae). Brit. Mus. Nat. Hist., London.

Netolitzky, F. 1920. Käfer als Nahrungs- und

Heilmittel. Koleop. Rund. 8: 21-26. Paprzycki, P. 1942. Datos para la captura y crianza del mas grande de los cerambícidos "Macrodontia cervicornis" en la selva peruana. Mus. Hist. Nat. Javier Prado (Lima) Bol. 6: 349-351.

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