Moronoserica Ahrens, Lukic & Liu, new genus

Type species: Microserica lineata Moser, 1915 (by present designation).

Diagnosis. Moronoserica Ahrens, Lukic & Liu, new genus differs from its sister clade (Fig. 1), Trioserica Moser, 1922, by the bidentate protibia, the dorsal surface being more or less strongly covered with white scale-like setae, the strongly convex elytral intervals, and most of all by the strongly derived shape of aedeagus. The latter have the left paramere almost entirely reduced, the dorsoapical emargination of phallobase between the parameres extremely deep, it exceeds at least the half of the phallobasal length (the genital characters appear to be likely the only unambiguous synapomorphies). In contrast to all other Microserica species, the dorsal margin of metatibia is not carinate but longitudinally convex.

The phylogeny based on molecular characters has shown that the group is not monophyletic with the remainder Microserica species. So far, the species of this group have been treated as Microserica lineata group (Ahrens 2004; Bohacz & Ahrens 2020). They are so far known only from Indochina.

Etymology. The genus name is composed by the root “ Serica ” (type genus of Sericini) and the name Morón. The new genus is dedicated to Miguel-Angel Morón (1952–2017), Mexican specialist of Melolonthinae, who passed away by far much too early.

Key to the species of Moronoserica Ahrens, Lukic & Liu, new genus (♁♁):

1 Phallobase short, about twice as long as wide in right side lateral view. Pronotum yellowish with one or two dark spots..... 4

- Phallobase long, more than three times longer than wide in right side lateral view. Pronotum uniformly brown........... 2

2 Dorsomedian emargination between parameres extremely deep, remanent part before phallobasal apodeme extremely short, always shorter that phallobase wide....................................................................... 5

- Dorsomedian emargination between parameres deep, but remanent part before phallobasal apodeme longer, at least as long as phallobase in this region wide............................................................................ 3

3 Dorsomedian emargination between parameres almost unilateral, only little longer than half total phallobase length. Right paramere narrow and short (length subequal to phallobase mesal width)... Mor. songbae Ahrens, Lukic & Liu, new species

- Dorsomedian emargination between parameres dorsomesal, much longer than half total phallobase length. Right paramere long (length much longer than phallobase mesal width) and wider........... Mor. thungyai Ahrens, Lukic & Liu, new species

4 Pronotum yellowish with one median dark spot. Right paramere long, its apex strongly widened apically. Antennal club little longer than the remaining antennomeres combined...................... Mor. lineata (Moser, 1915) new combination

- Pronotum yellowish with two symmetric dark spots beside the dark midline. Right paramere short, its apex weakly widened apically. Antennal club twice as long as the remaining antennomeres combined............................................................................................... Mor. geberbauer (Ahrens, 2004) new combination

5 Left lateral process of phallobase strongly widened apically but straight.......................................... 7

- Left lateral process of phallobase narrow and not widened apically.............................................. 6

6 Left lateral process of phallobase strongly hooked ventrally at apex. Body densely covered with small white setae. Body smaller, 6.8–7.1 mm. Anterior margin of metafemur with serrated line.................................................................................................... Mor. crenatostriata (Ahrens, 2004) new combination

- Left lateral process of phallobase evenly narrowed towards apex. Serrated line beside anterior margin of metafemur and beside dorsal margin of metatibia lacking................... Mor. tenasserimensis (Bohacz & Ahrens, 2020) new combination

7 Ventral lamina of left side of phallobase strongly produced ventrally, phallobase results distally strongly widened.............................................................. Mor. ventrosa (Bohacz & Ahrens, 2020) new combination

- Ventral lamina of left side of phallobase not produced, phallobase distally not widened.............................. 8

8 Body densely covered with small white scales or setae........................................................ 9

- Body sparsely covered with small white scales, only with dense, white minute setae............................... 10

9 Body densely covered with small white scales. Right paramere short and wide................................................................................................. Mor. squamulata (Moser, 1915) new combination

- Body densely covered with small white setae. Right paramere more elongate and narrower.................................................................................. Mor. squamulatoides Ahrens, Lukic & Liu, new species

10 Right paramere robust and elongate, width subequal to maximum phallobase width................................ 13

- Right paramere narrow, width much narrower than maximum phallobase width................................... 11

11 Right paramere straight and rounded at apex...................... Mor. banmethout Ahrens, Lukic & Liu, new species

- Right paramere curved and sharply pointed................................................................ 12

12 Odd intervals of elytra without long, erect setae. Left lamina of phallobase with only a small preapical ventral hook. Right paramere wide and weakly curved.......................... Mor. helferi (Bohacz & Ahrens, 2020) new combination

- Odd intervals of elytra with long, erect setae. Left lamina of phallobase with a large hook before apex. Right paramere narrower and more strongly curved......................................... Mor. renong Ahrens, Lukic & Liu, new species

13 Base of labroclypeus dull. Dorsal margin of right paramere evenly curved (lateral view).................................................................................... Mor. ginae (Bohacz & Ahrens, 2020) new combination

- Base of labroclypeus shiny. Dorsal margin of right paramere strongly bent at middle and concave basally (lateral view)........................................................ Mor. banvaneue (Bohacz & Ahrens, 2020) new combination