Macronemus Dejean, 1835

Machado, Vanessa S. & Monné, Marcela L., 2013, The genus Macronemus Dejean, 1835 (Insecta: Coleoptera: Cerambycidae: Lamiinae): two new species, new records and a new synonymy, Zootaxa 3693 (2), pp. 163-181 : 164-166

Macronemus Dejean, 1835

Macronemus Dejean, 1835: 337 ; Monné, 2005: 177; Monné, 2012: 78. Type species: Lamia antennator Fabricius, 1801 , by monotypy. Aethomerus Thomson, 1861: 338 .

Type species: Aethomerus filicornis Thomson, 1861 , by monotypy.

Eyes coarsely faceted. Frons vertical with decumbent setae near base, and few brown decumbent and erect setae between lower ocular lobe and base of the antennal tubercles. Lower ocular lobes oval. Apical segments of labial and maxillary palps distinctly acuminate at apex. Genae slightly projected. Antennal tubercles projected and directed posteriorly. Antennae filiform, long, exceeding elytral apices, in both sexes, at antennomeres 5 or 6.with short, erect brown setae throughout. Scape at least 2.0x as long as antennomere 3; antennomere 3 at least subequal to 4 in length; antennomeres 4–6 subequal in length; antennomeres 7–11 increasing in length; antennomere 11 about 2.0x longer than 3. Scape clavate, short, narrowed at base. Pedicel short, cylindrical.

Prothorax transverse; armed with lateral tubercle. Pronotum with pair of antemedian tubercles; row of punctures on posterior and anterior margins; punctures between the tubercles. Prosternal process narrow, about 4.0x as broad as coxal cavity; anterior coxal cavities closed behind. Intermediate coxal cavities open to epimera. Scutellum truncated or rounded at apex.

Elytra about 3.0 or 4.0x as long as prothorax, with cristae at base, wider than prothorax on the base, slightly depressed in median region, gradually narrowing toward apices; fine punctures throughout. Humeri rounded and slightly prominent.

Mesolegs longer than pro- and metalegs. Pro- and mesocoxae rounded; procoxae more prominent, with sulcus. Femora pedunculate-clavate with rounded, glabrous spot on inner dorsal surface. Profemora clavate, more swollen than others. Mesofemora with short peduncle. Metafemora with elongate peduncle. Protibiae curved, with longitudinal median sulcus in ventral region; meso- and metatibiae linear. Tibiae and femora subequal in length. First segment of metatarsus twice longer than second.

First urosternite at least 2.5x longer than next; 2–4 subequal in length. Fifth urosternite with sexual dimorphism: in males, basal third with continuous pilosity and apex not excavated ( Figs. 3 , 7 , 14 ); in females, with narrow longitudinal glabrous and smooth band and apex excavated ( Figs. 4 , 10 , 15 ).

Comments. Lacordaire (1872) considered Aethomerus similar to Alphus White, 1855 ( Alphus similis Martins, 1985 , Figs. 43–47 ), the latter differing in being smaller and notably narrower, and the elytra with cristae at the base and granules.

Macronemus is similar to Alphus with respect to the absence of long hairs on the body, the procoxae with a longitudinal median sulcus, and the pronotum and sides of the prothorax with tubercles. Macronemus differs from Alphus in the extremely long antennae, exceeding the elytral apices at antennomere 5 or 6, without sexual dimorphism, and antennomere 11 at least 2.0x longer than 3; scaly pubescence; protibiae curved and fifth urosternite with sexual dimorphism. In Alphus the antennae are long, exceeding the elytral apices at antennomere 7, with sexual dimorphism, males with antennomere 11 modified at the apex ( Fig. 45 ) and about 1.3x shorter than 3; pubescence filiform, not scaly; protibiae linear; procoxae with longitudinal median sulcus and fifth urosternite without sexual dimorphism ( Figs 44, 47 ).

Tippmann (1953) considered Pseudaethomerus ( Pseudaethomerus lacordairei Bates, 1862 , Figs 48–51 ) similar to Aethomerus , a synonym of Macronemus , because of the femora having large, planar, well-defined spots, shaped like a mirror; the latter differing in having the antennae shorter and stronger; antennomere 11 shorter and subequal to 3 in length; and the body thicker and robust.

Macronemus is similar to Pseudaethomerus with respect to the prothorax armed with a lateral tubercle; the pronotum with a pair of projections; the femora with a rounded, glabrous spot on the inner surface; and the apex of the fifth urosternite of the females excavated and with a glabrous band at the base. Macronemus differs from Pseudaethomerus by the narrow antennomeres 3–4; the profemora without a rounded, glabrous spot on the outer surface; and the protibiae curved. In Pseudaethomerus (Figs 48,50) antennomeres 3–4 are thick; the profemora have a rounded, glabrous spot on the outer surface, and are robust; and the protibiae are linear.

Figures

FIGURES 1 – 4. Macronemus analis (Pascoe, 1866). 1 – 2, females dorsal view; 3, male fifth urosternite; 4, female fifth urosternite.

FIGURES 5 – 11. Macronemus rufescens (Bates, 1862). 5 – 6, holotype, male: 5, dorsal view; 6, labels; 7 – 8, male: 7, fifth urosternite; 8, protibial spine; 9 – 11, female: 9, dorsal view; 10, fifth urosternite; 11, profemora with inferior margin projected near base and longitudinal, glabrous band.

FIGURES 12 – 17. Macronemus giuglarisi sp. nov. 12, holotype, male, dorsal view; 13, male, dorsal view; 14, male fifth urosternite; 15, female fifth urosternite; 16, male protibia with a long apical spine; 17, female protibia apex slightly projected, without spine.

FIGURES 43 – 47. Alphus similis Martins, 1985. 43 – 45, male: 43, dorsal view; 44, fifth urosternite; 45, detail of the antennomere 11 modified at the apex; 46 – 47, female: 46, dorsal view; 47, fifth urosternite.

FIGURES 48 – 51. Pseudaethomerus lacordairei (Bates, 1862). 48 – 49, male: 48, dorsal view; 49, fifth urosternite; 50 – 51, female: 50, dorsal view; 51, fifth urosternite.