1	Elytral disc broadly, deeply transversely impressed with a saddle-like depression from scutellum to declivital base; declivity deeply sulcate, its margins costate; elytral bases slightly emarginated to accommodate a prominent and dense mycangial tuft	2
–	Elytral disc either medially impressed and appearing humped, or flat, or broadly convex; declivity round or flat or convex; elytral bases not emarginated and mycangial tuft minute, either not readily apparent or lightly setose	3
2	Elytral base emargination broadly recurved; elytral disc shallowly depressed; declivital summit armed with a pair of large tubercles at interstriae 1; punctures on declivity distinct and broad; larger species, 3.0–3.1 mm	cruralis
–	Elytral base emargination broadly V-shaped; elytral disc deeply depressed, more deeper posteriorly; interstriae 1 on declivital summit without a pair of large tubercles; punctures on declivital face small and indistinct; smaller species, 2.12 mm	exsculptus
3	Posterolateral margin of elytra smoothly rounded, without any indication of a costa or carina	4
–	Posterolateral margin of elytra marked by an elevated costa or carina	5
4	Elytral lateral margin tapering posteriorly from the middle to apex; elytral apex acute; minute species, 1.12–1.24 mm	nanus
–	Elytral lateral margin subparallel, broadly tapering posteriorly; apex broadly rounded, not acute; larger species, 1.60 mm	globodeclivis sp. nov.
5	Declivity obliquely truncate; posterolateral declivital margin rounded and denticulate	6
–	Declivity rounded; posterolateral declivital margin costate or carinate, with or without granules	9
6	Declivital interstriae 2 and 3 strongly laterally broadened from base to de­clivital midpoint and then narrowing towards apex	latesalebrinus
–	Declivital interstriae parallel from base to apex, never laterally broadened	7
7	Denticles on declivital summit and margins larger and more sharply acute than those on declivital face	kirishimanus
–	Denticles on declivital summit of equal size and shape as those on declivital face	8
8	Denticles on declivital summit as dense as those on declivital face; declivital face opalescent, subshiny	nudibrevis
–	Denticles on declivital summit denser than those on declivital face; declivital face shagreened, dull	perparvus
9	Larger, 2.55–2.95 mm	10
–	Smaller, 1.2–2.1 mm	12
10	Stout, 1.93–2.19× as long as wide; elytral posterolateral margin strongly carinate and unarmed	fulvulus
–	Elongate, 2.5–2.9× as long as wide; elytral posterolateral margin costate and granulate	11
11	Declivital strial punctures very large, distinct	chrysophylli
–	Declivital strial punctures small, indistinct	corporaali
12	Declivity with granules, denticles or tubercles distinctly less abundant than strial punctures	13
–	Declivity with abundant granules or denticles, at least as abundant as strial punctures	19
13	Elytral disc shallowly transversely impressed with a saddle-like impression	14
–	Elytral disc without a depression	15
14	Discal impression deeper, antero-posteriorly narrower, with steeper anterior and posterior slopes, strial punctures on impression with rounded granules; interstrial spines on disc behind impression stronger and backwardly hooked	sagmatus
–	Discal impression shallower, antero-posteriorly broader, with gentler anterior and posterior slopes, strial punctures on impression without granules; interstrial tubercles on disc behind impression moderate with rounded apices pointing dorsally	undulatus
15	Declivital tubercles uniformly sized	16
–	Declivital tubercles not uniformly sized, 1–2 pairs of larger tubercles on declivital interstriae 3	17
16	Posterolateral declivital margin carinate, unarmed	alpha
–	Posterolateral declivital margin costate and denticulate	bucolicus sp. nov.
17	Declivity steeply rounded, declivital interstriae 1 bearing 1–2 small tubercles on declivital face; larger, 1.9–2.0 mm	recidens
–	Declivity gradually rounded, declivital interstriae 1 unarmed on declivital face; smaller, 1.66–1.76 mm	18
18	Declivital interstriae 3 with two pairs of prominent denticles; posterior half of elytral disc rugose with deeply impressed striae and costate interstriae, interstriae bearing strong incurved spines that become more prominent toward declivital summit	serratus sp. nov.
–	Declivital interstriae 3 with one pair of prominent tubercles; posterior half of elytral disc smooth, striae and interstriae flush, interstriae with a few small tubercles at summit	bidentatus sp. nov.
19	Elytral disc convex on basal 1/3, appearing humped in lateral view	20
–	Elytral disc flat, never appearing humped	22
20	Declivital interstriae densely covered with short semi-erect scales	kadoyamaensis
–	Declivital interstriae densely covered with long fine, erect hair-like setae	21
21	Antennal club flat, type 3 with two sutures visible on apical 1/3 of posterior face; larger, declivity smooth, shiny; larger, 1.95–2.0 mm and more elongate, 2.79–2.86× as long as wide	minax
–	Antennal club obliquely truncate, type 2 with segment 1 almost covering posterior face (Fig. 2); one suture visible on posterior face near apex; declivity shagreened, dull; smaller, 1.8–1.9 mm and less elongate, 2.57–2.71× as long as wide	nugax
22	Antennal club flat, type 3 with two sutures visible on apical 1/3 of posterior face (Fig. 3	diversicolor
–	Antennal club obliquely truncate, type 2 with segment 1 almost covering posterior face; one suture visible on posterior face near apex	23
23	Declivital interstrial granules dispersed, separated by the width of at least three granules; posterolateral margin of declivity weakly carinate and granulate; interstrial vestiture consisting of short semi-erect bristles, shorter in length than the width of an interstria; smaller, 1.2–1.7 mm	pometianus
–	Declivital interstrial granules dense, separated by the width of one granule; posterolateral margin of declivity strongly carinate; interstrial vestiture consisting of long semi-erect hair-like setae, longer in length than the width of an interstria (easily abraded); larger, 1.8–2.0 mm	quercicola