Aethina (Idaethina) subrugosa (Grouvelle, 1894)

Dasgupta, Jhikmik & Pal, Tarun Kumar, 2022, On Aethina Erichson of Northeast India (Coleoptera: Nitidulidae: Nitidulinae), Zootaxa 5124 (5), pp. 533-550 : 547-548

7. Aethina (Idaethina) subrugosa (Grouvelle, 1894)

Macroura subrugosa Grouvelle, 1894a: 461 .

Aethina (Ollifura) subrugosa: Kirejtshuk, 1986: 81 .

Macroura dubia Grouvelle, 1894a: 461 . (Synonymised by Kirejtshuk & Lawrence, 1999)

Aethina (Idaethina) subrugosa: Kirejtshuk & Lawrence, 1999: 252 .

Diagnosis. Body ( Figs. 21–22 ) oblong-ovate, chestnut-brown, moderately shiny; apex of pygidium somewhat emarginate; pronotum with coarse, round punctures; elytra with somewhat oval punctures arranged in linear longitudinal rows; dorsum covered with sparse, short, grey, setae appressed to the surface.

Head transverse, frons feebly depressed; punctation on frons round, about 2× of eye facets, moderately deep, separated by 1–2 diameter of punctures; punctures on vertex sparse, round, distinct, rather deep, diameter about 4.5× the size of the eye facets, separated by about 0.75–1 diameter of punctures; setae on frons and vertex golden, moderately long and dense, decumbent, anteriorly directed; eyes large and moderately projected, about 0.4× as long as head, outer margin rounded, finely facetted. Antenna about 1.2× as long as head; antennal club about 1.3× as long as broad, about 0.3× as long as antenna.

Prothorax transverse (l.0: 1.9), anterior margin deeply emarginate; sides arcuate, posterior margin bisinuate, anterior angles sharply obtuse, posterior angles somewhat pointed. Pronotum rather convex, surface distinctly punctate, punctures round, moderately deep, about as coarse as those on vertex, separated on top of pronotal disc by 0.5–1 diameter; closely appressed, moderately long, blackish setae present on disc.

Scutellar shield transverse, about 1.7× as broad as long, boat-shaped with truncate apex, with a subtle excision at middle, corners rounded; punctures 0.5× as those on pronotum, separated by 1–2 diameter of punctures, setae short, blackish, appressed to the surface and posteriorly directed.

Elytra together about 1.1× as broad as long, anterior margin closely fitting with hind margin of prothorax, humeral angles right-angled, sides uniformly arcuate, apices separately rounded; punctures oval, distinct, moderately coarse and deep, almost 2× as those on pronotum, arranged in distinct, longitudinal rows; setae short, closely appressed with the surface and posteriorly directed.

Exposed portion of abdominal tergites about 1.6× as broad as long, part of the anal sclerite in males exposed underneath the pygidium; setae short, closely appressed to the surface of the abdomen, posteriorly directed.

Ventral side ( Fig. 22 ) uniformly dark-brown; gular region of head with subparallel antennal grooves running posterad. Metaventrite punctate, mesocoxal lines reaching almost up to two-thirds the length of the metaventralmetanepisternal suture from base, thereby making a distinct axillary space.

Aedeagus ( Figs. 16, 17 ): Parameres trowel-shaped with rounded apex, sides gradually narrowed from base to apex, short setae present on posterior half of the lateral margin. Median lobe elongated-hexagonal in shape with pointed apex.

Measurements (in mm): Total length 2.88–3.21, width of head across eyes 0.49–0.53, length of antenna 0.55– 0.61, length and width of prothorax 0.86–1.00 and 1.63–1.82, length and width of elytra together 1.42–1.60 and 1.55–1.85.

Material examined. 4 ex. INDIA: Arunachal Pradesh, Lohit Dist. , Jecko, 13 km-O-Sunpura , 2 ex., 29.ix.1991, T. K. Pal, ex. flower ; 2 ex., Mizoram, Aizawl Dist., Teirei, Dampa WLS, 20.x.1991, J. K. Jonathan .

Distribution. INDIA: Arunachal Pradesh (new record), Mizoram (new record), Karnataka, Uttarakhand; CHINA; NEPAL; THAILAND; VIETNAM.

Figures

FIGURES 19–24. 19, 21, 23, (dorsal habitus): 19, Aethina (Idaethina) orientalis (Nietner, 1856); 21, Aethina (Idaethina) subrugosa (Grouvelle, 1894); 23, Aethina (Circopes) subquadrata (Motschulsky, 1858); 20, 22, 24, (ventral habitus): 20, Aethina (Idaethina) orientalis (Nietner, 1856); 22, Aethina (Idaethina) subrugosa (Grouvelle, 1894); 24, Aethina (Circopes) subquadrata (Motschulsky, 1858).

FIGURES 10–18. 10–17: Aethina (Idaethina) subrugosa (Grouvelle, 1894), line drawings: 10, mandible, dorsal view; 11, maxilla, ventral view; 12, labium, ventral view; 13, labrum, dorsal view; 14, anal sclerite (tergite VIII) and spiculum gastrale; 15, ovipositor; 16, male genitalia: tegmen, ventral view; 17, male genitalia: median lobe, ventral view; 18, Aethina (Idaethina) orientalis (Nietner, 1856) male genitalia: tegmen and median lobe.