Megauchenia indica ( Grouvelle, 1908 )

Dasgupta, J., Pal, T. K. & Hegde, V. D., 2015, Review of the Megauchenia Macleay of India (Coleoptera: Nitidulidae: Prometopinae), Zootaxa 4058 (4), pp. 551-560 : 559-560

Megauchenia indica ( Grouvelle, 1908)

Ischaena indica Grouvelle 1908: 357 .

Megauchenia indica: Grouvelle 1913a: 136 ; Jelínek & Audisio 2007: 473.

Diagnosis. Body ( Figs. 29–30 ) elongate-ovoid, dark brown to black, moderately shiny. Lateral margin of pronotum arcuate. Elytral sides subparallel with apices gently arcuate and margin uniformly rounded, elytral punctures not arranged entirely in regular rows, striations partially erased and punctation confused in areas; coarsely punctate dorsum with rows of striae on each elytron bearing sparse, short golden and erect setae.

Head transverse, about as broad as long, frons depressed; punctation on frons round, distinct, diameters about 3x larger than those of vertex, separated by about 0.25–0.5 diameter of punctures; punctures on vertex finer than those on frons, oval and distinct; setae on frons indistinct; eyes large and moderately projected, outer margin rounded, coarsely facetted, about 0.3x as long as head, temple short and rounded behind the eye; ocular border of head slightly carinate. Antenna about 1.4x as long as head; antennal club about 1.2x as long as broad, club segments somewhat compact and closely attached, about 0.27x as long as antenna.

Prothorax transverse, about 1.3x as broad as long, anterior margin slightly emarginate; sides arcuate, posterior margin bisinuate with a distinct emargination at the middle, anterior angles broadly pointed, posterior angles obtusely rounded. Pronotum moderately convex with a shallow longitudinal depression near either side of the pronotal disc, surface distinctly punctate, punctures round and smaller on disc and hexagonal and larger near sides, dense, distinct, separated on top of pronotal disc by 1–2 diameters and near sides by 0.25–0.5 diameters of punctures, setae on disc indistinct.

Scutellar shield transverse, about 1.3x as broad as long, triangular and somewhat pointed apically; punctures round, small, about 0.3x the diameter of elytral punctures; setae rather short, golden and decumbent.

Elytra together about 1.4x as long as broad, humeral angles projected anteriorly, sides slightly arcuate and feebly explanate, apices separately rounded; punctures confused, near basal part of elytral suture punctures are deeper and more distinct than in remaining part of elytra, size of punctures almost similar to those on pronotum, arranged in longitudinal rows, separated by 0.75–1 diameter; setae short, erect, posteriorly directed and arranged along alternate striae; striae more distinct near apex, first, third and fifth striae complete while second, fourth and sixth striae obscure before middle of each elytron and replaced by irregularly arranged punctures.

Pygidium about 2.1x as broad as long. Punctures on first and second abdominal ventrites small and indistinct, punctures on third, fourth and fifth ventrites slightly oval and larger than other ventrites; setae moderately long, uniformly arranged, closely appressed to the surface of the abdomen, posteriorly directed.

Ventral side dark brown, legs and antennae dark reddish; gular region of head with posteriorly converging antennal grooves. Mesoventrite almost as broad as long, a single median longitudinal carina present; metaventrite with mesocoxal lines reaching almost the end of the metaventral-metanepisternal suture, thereby creating a distinct axillary space.

Aedeagus: Not studied.

Measurements (in mm): Total length 6.91, width of head across eyes 1.02, length of antenna 1.44, length and

width of prothorax 1.83 and 2.51, length and width of elytra together 4.23 and 3.00. Material examined. INDIA, Nilgiri Hills, H. L. Andrews, 1 ex. (Reg. No. 3752/21). Distribution. INDIA: Tamil Nadu.

Figures

FIGURES 19 – 30. 19, 21, 29 (dorsal habitus): 19, Megauchenia angustata (Erichson, 1843); 21, M. quadricollis (Reitter, 1883); 29, M. indica (Grouvelle, 1908); 20, 22, 30 (ventral habitus): 20, M. angustata; 22, M. quadricollis; 30, M. indica. 23 – 28: male genitalia: 23, tegmen and median lobe of M. angustata, microphotograph; 24, median lobe of M. angustata after separating from tegmen, microphotograph; 25, tegmen and median lobe of M. quadricollis, microphotograph; 26, median lobe of M. quadricollis after separating from tegmen, microphotograph; 27, tegmen of M. quadricollis, line drawing; 28, median lobe of M. quadricollis, line drawing.