Premnobius ambitiosus (Schaufuss)

Atkinson, Thomas H., Flechtmann, Carlos A. H. & Petrov, Alexander V., 2023, Synopsis of the Neotropical Premnobiina (Coleoptera: Curculonidae: Scolytinae Ipini) with descriptions of new species, new synonymy and keys to species, Zootaxa 5249 (1), pp. 69-91 : 73-74

Premnobius ambitiosus (Schaufuss)

Fig. 5 C,D

Xyleborus ambitiosus Schaufuss, 1897: 109 .

Premnobius ambitiosus (Schaufuss) : Eggers 1922: 173.

Premnobius cavipennis spinosus Hagedorn, 1908: 376 . Synonymy: Eggers 1922: 173.

Premnobius brasiliensis Nunberg, 1960: 490 . Synonymy: Schedl 1960: 107.

Similar species. This is the largest and most robust species found in the Neotropical region. It most closely resembles P. cavipennis , but is much larger.

Diagnosis. Length 3.0– 3.3 mm, 3.0 × as long as wide ( Wood 2007: 368). Color dark reddish brown, body covered with fine, short pubescence. Frons granulate-punctate, with a faint longitudinal carina extending to the epistoma. Anterior margin of pronotum rounded, without marginal teeth. Pronotal summit slightly before middle, anterior asperities small and irregular. Elytral disc with interstriae 4 × as wide as striae, striae not impressed. Vestiture of recumbent strial setae, with mostly uniseriate strial setae, these becoming longer and stouter posteriorly. Declivity occupying about 40% of elytral length, the basal portion of first interstriae depressed; raised posterolateral crest beginning on interstria 2 and continuing to apex. Declivital face weakly concave, with large confused strial and interstrial punctures, pubescence absent. Crest with irregular denticles throughout. Longest near middle, toothlike, slightly incurved; a much smaller tooth at base of declivity on interstria 3. Marginal teeth and denticles on crest shorter than surrounding pubescence.

Distribution: Introduced from the Afrotropical region. The earliest collection records in Colombia and Brazil are from 1958. Widely distributed in South America and Panama to south-central Brazil ( Fig. 12 B ). This is a large and distinctive species and it is surprising that there are so few records.

Figures

FIGURE 5. Dorsaland posterolateral views of declivities of Neotropicalspecies of Premnobius, part 2.A,B. P.browneiAtkinson & Flechtmann; C,D. P. ambitiosus (Schaufuss); E,F. P. cavipennis Eichhoff. Photographs by T.H. Atkinson.

FIGURE 12. Known localities for Neotropical species of Premnobiina. A. Premnobius cavipennis; B. Premnobius ambitiosus; C. Premnobius perezdelacrucei; D. Premnobius species.; E,F. Premnophilus species. Species are grouped only to avoid overlap of collection localities on maps. No ecological or systematic relationships are implied.