A revision of the Maechidiini Burmeister, 1855 (Coleoptera: Scarabaeidae: Melolonthinae) from the Indo-Australian transition zone, and the first record of the tribe west of Wallace’s Line
Author
Telnov, Dmitry
text
European Journal of Taxonomy
2020
2020-10-19
721
1
210
journal article
9693
10.5852/ejt.2020.721.1127
0cd61b23-1089-4c1b-bfc0-487887abad84
4122118
89E62EF8-2E45-4C59-94B7-6A5603E8939B
Maechidius sturnus
Arrow, 1941
Figs 87
,
181
,
254
,
347
, 419, 433, 523, 563, 721–723
Type material
Holotype
INDONESIA
•
♂
; “
Type
[p, label circular, red frame] //
DUTCH
NEW
GUINEA
:
Japen
[sic
♂
] I.,
R
.Manai–Undei.
500 ft.
,
x. 1938
.
L.E.Cheesman.
B.M.1938–593 [p] //
Maechidus
sturnus
,
type
Arrow [h]”;
BMNH
.
Description
Dorsum and venter uniformly black, edges of labroclypeus, lateral margins of pronotum, legs and antennae brown. Male labroclypeus (
Fig. 181
) broadly emarginate on anterior margin, its lateral margins sinuous in both dorsal and lateral views. Anterolateral angles of labroclypeus obtuse, slightly protruding. Canthus nearly straight in dorsal view. Head punctures irregularly hexagonal, dense, moderately deep. Intervening spaces glossy, in part wrinkled. At least areas around either compound eye covered with microscopical velvety pubescence. Head setae minute, rise from anterior margin of corresponding punctures, not surpassing its length. Pronotum sinuous on anterior margin, anterolateral angles slightly protruding. Basal margin of pronotum somewhat obtuse angulate medially. Lateral margin of pronotum in dorsal view broadly rounded, gradually constricted postmedially towards base, crenulate all along (
Fig. 254
). Inconspicuous appressed scale-like seta present between every two crenulae. Lateral margin of pronotum sinuous in lateral view. Hypomeron slightly emarginate and long setose on anterior margin which is flange-like protruding. Antennal pocket deep. Pronotal punctures irregularly ovoid, very deep, dense, arranged in different directions. Intervening spaces glossy, in part wrinkled, variably large. Lateral margins, antero- and posterolateral angles completely covered with delicate microscopical velvety pubescence. Pronotal setae similar to those on head. Elytra cylindrical, subopaque. Elytral punctures ovoid, deep and dense, arranged irregularly (
Fig. 347
). Intervening spaces in part subopaque, in part glossy, wrinkled, generally smaller than punctures. Elytral setae minute, rise from anterior margin of corresponding puncture, not surpassing its midlength. With few longer scale-like suberect clavate setae scattered over elytral disc; punctures bearing those longer setae partly or completely encircled with microscopical velvety pubescence (
Fig. 347
). Male abdominal sternites medially with somewhat longer and curved scale-like setae. Posterior margin of male abdominal sternites 2 and 3 each with bunch of three long setae on either side near middle (
Fig. 433
). Male pygidium with ovoid deep moderately large punctures (Fig. 523). Intervening spaces glossy to subopaque, generally larger than punctures. Setae of pygidium minute on anterior part (not surpassing length of corresponding punctures), longer on median and posterior parts (hardly surpassing length of corresponding punctures), becoming suberect and longer along distal margin. Surface of pygidium perimeter and narrow longitudinal midline covered with microscopical velvety pubescence. External margin of male protibia arched, with single acute distal tooth on external margin (Fig. 419). Spiculum gastrale as in
Fig. 563
. Aedeagus as in
Figs 721–723
.
Sexual dimorphism
Female is unknown.