Tetraserica Ahrens 2004
Creators: name: Ahrens, Dirk
name: Lukic, Daniel
name: Pham, Phu
name: Li, Wei
name: Liu, Wangang
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Scarabaeidae
Tetraserica

description: Updated key to continental Southeast Asian species of Tetraserica Ahrens, 2004 (♁♁):
1 Species from Indochina or China ......................................................................... 2
- Species from Indian subcontinent...................................................................... 147
2 Posterior margin of metafemur straight or slightly convex.................................................... 23
- Posterior margin of metafemur with blunt tooth or sharp hook.................................................. 3
3 Posterior margin of metafemur with blunt tooth.............................................................. 4
- Posterior margin of metafemur with sharp hook............................................................. 14
4 Left paramere long and narrow........................................................................... 5
- Left paramere short and stout............................................................................ 9
5 Median lamina of phallobase as long or nearly as long as phallobase............................................. 6
- Median lamina of phallobase less than ¼ as long as phallobase. Left paramere long and filiform....................... 8
6 Left paramere as long as phallobase or longer, straight, not filiform.............................................. 7
- Left paramere nearly half as long as phallobase, curved externally, filiform................. T. vietnamensis (Frey, 1972)
- Left paramere more than half as long as phallobase. Left paramere split shortly before apex into two filiform but flattened branches................................................... T. multiangulata Fabrizi, Dalstein & Ahrens, 2019
7 Right paramere split in two lobes.......................... T. pingjiangensis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Right paramere simple.................................... T. semipingjiangensis Fabrizi, Dalstein & Ahrens, 2019
8 Right paramere shorter than phallobase, its dorsal lobe short and basally directed........... T. takahashii Kobayashi, 2017
- Right paramere as long as phallobase, its dorsal lobe long and distally directed.............................................................................................. T. phoupaneensis Fabrizi, Dalstein & Ahrens, 2019
9 Dorsal lobe of right paramere bearing spines. Median apical phallobasal lamina basolaterally strongly enlarged towards a lateral lamina as well............................................................... T. khemoi Ahrens, new species
- Dorsal lobe of right paramere bearing no spines. Median apical phallobasal lamina basolaterally not enlarged........... 10
10 Dorsal lobe of right paramere short, not exceeding length of ventral one.............................................................................................. T. maoershanensis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Dorsal lobe of right paramere longer, exceeding length of ventral one........................................... 11
11 Left paramere more narrow, dorsal margin weakly and evenly curved...................................................................................................... T. sculptilis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Left paramere stout, dorsal margin bluntly angulate.......................................................... 12
12 Dorsal lobe of right paramere evenly curved. Apex of left paramere abruptly narrowed at apex............................................................................. T. daqingshanica Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Dorsal lobe of right paramere in basal half wide and straight, in apical half curved. Apex of left paramere gently narrowed at apex............................................................................................... 13
13 Left paramere one quarter as wide as length of antennal club........... T. neouncinata Fabrizi, Dalstein & Ahrens, 2019
- Left paramere two thirds as wide as length of antennal club......... T. pseudouncinata Fabrizi, Dalstein & Ahrens, 2019
14 Metafemur basally not widened......................................................................... 15
- Metafemur basally strongly widened, sharp hook behind basal quarter of metafemur............. T. spinicrus (Frey, 1972)
15 Sharp hook behind basal third of metafemur................................................................ 16
- Sharp hook at middle of metafemur.............................................. T. hubleyi Ahrens, new species
16 Eyes smaller, ratio diameter/interocular distance ≤ 0.59...................................................... 17
- Eyes larger, ratio diameter/interocular distance ≥0.63. Dorsal lobe of right paramere very small and bent basally......... 21
17 Left paramere with two branches........................................................................ 18
- Left paramere simple. Dorsal lobe of right paramere longer than the ventral one................................... 20
18 Left paramere split into a dorsal hook and a basal filiform branch. Dorsal lobe of right paramere much shorter than the ventral one............................................................................................... 19
- Left paramere split into two similar branches (lateral view). Dorsal lobe of right paramere longer than the ventral one........................................................................ T. lucai Fabrizi, Dalstein & Ahrens, 2019
19 Dorsal hook of smaller basal lobe of left paramere short. Basal lobe of right paramere small.Apical phallobasal lamina distinctly longer, distinctly exceeding dorsal lobe of left paramere............... T. kontumensis Fabrizi, Dalstein & Ahrens, 2019
- Dorsal hook of distinctly larger basal lobe of left paramere longer and strongly curved. Basal lobe of right paramere more robust. Apical phallobasal lamina distinctly shorter, not exceeding dorsal lobe of left paramere.................................................................................... T. semikontumensis Pham & Ahrens, new species
20 Dorsal lobe of right paramere strongly curved, large and directed distally, exceeding ventral lobe by far, at apex with a small additional hook.......................................... T. liangheensis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Dorsal lobe of right paramere weakly curved, weakly exceeding ventral lobe, at apex without additional hook...................................................................... T. doisuthepensis Fabrizi, Dalstein & Ahrens, 2019
21 Median lamina of phallobase evenly narrowed from base to apex, sharply pointed at apex. Basal portion of right paramere (lateral view) much wider than apical part.................... T. wandingensis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Median lamina of phallobase wide, abruptly narrowed and rounded at apex. Basal portion of right paramere (lateral view) not wider than apical part................................................................................. 22
22 Right paramere strongly bent at middle (lateral view)............................ T. wiangpapaoana Kobayashi, 2017
- Right paramere weakly bent at middle (lateral view)................................ T. masumotoi Kobayashi, 2017
23 Median lamina of phallobase short, at maximum subequal to length of phallobase................................. 24
- Median lamina of phallobase long, at least slightly longer than phallobase....................................... 94
24 Median lamina of phallobase medium in length, at maximum subequal to length of phallobase....................... 25
- Median lamina of phallobase short, subequal to at maximum half of length of phallobase........................... 44
25 Right paramere at base without spines.................................................................... 26
- Right paramere at base with a comb of short spines.................. T. quadriforceps Fabrizi, Dalstein & Ahrens, 2019
26 Right paramere simple................................................................................ 27
- Right paramere with a dorsal and a ventral lobe. Metatibia robust, ratio length/width ca. 1/3.0........................ 42
27 Left paramere simple................................................................................. 28
- Left paramere split into two long and narrow filiform lobes................................................... 32
28 Right paramere as long as phallobase. Metatibia slender, ratio length/width ca. 1/ 3.4. Median lamina of phallobase evenly wide and rounded at apex....................................... T. shunbiensis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Right paramere shorter than phallobase................................................................... 29
29 Right paramere one third as long as phallobase. Metatibia stouter, ratio length/width ca. 1/ 3.1....................... 31
- Right paramere half as long as phallobase................................................................. 30
30 Left paramere before apex with a blunt lateral tooth. Right paramere slightly shorter than medial phallobasal lamina................................................................ T. champassakana Fabrizi, Dalstein & Ahrens, 2019
- Left paramere before apex without blunt lateral tooth. Right paramere as long as medial phallobasal lamina........................................................................... T. doipuiensis Fabrizi, Dalstein & Ahrens, 2019
31 Left paramere nearly straight. Median lamina of phallobase narrowed distally, curved dorsally and with a dorsal tooth at apex............................................................ T. nahaeoensis Fabrizi, Dalstein & Ahrens, 2019
- Left paramere strongly and evenly curved ventrally. Median lamina of phallobase narrowed distally, curved dorsally and with a dorsal tooth at apex........................................ T. pahinngamensis Fabrizi, Dalstein & Ahrens, 2019
32 Dorsal lobe of left paramere shorter than ventral lobe........................................................ 33
- Dorsal lobe of left paramere distinctly longer than the ventral one. Apex of median phallobasal lamina moderately pointed. 39
33 Dorsal lobe of left paramere less than half as long as ventral lobe............................................... 34
- Dorsal lobe of left paramere slightly more than half as long as ventral lobe.................... T. wapiensis (Frey, 1972)
34 Right paramere distinctly shorter than median lamina of phallobase............................................ 35
- Right paramere approx. as long as median lamina of phallobase................................................ 37
35 Apex of median phallobasal lamina blunt and curved abruptly dorsally. Right paramere bent only once............................................................................. T. kiriromensis Fabrizi, Dalstein & Ahrens, 2019
- Apex of median phallobasal lamina sharply pointed......................................................... 36
36 Right paramere bent twice. Dorsal lobe of left paramere half as long as ventral lobe. Median lamina of phallobase distinctly shorter than remainder phallobase.............................. T. banhuaipoensis Fabrizi, Dalstein & Ahrens, 2019
- Right paramere bent once only. Dorsal lobe of left paramere 1/4 as long as ventral lobe. Median lamina of phallobase as long as remainder phallobase..................................................... T. hornburgi Ahrens, new species
37 Right paramere bent twice, slightly narrower in lateral view. Apex of median phallobasal lamina sharply pointed........ 38
- Right paramere bent only once, slightly wider in lateral view. Apex of median phallobasal lamina strongly rounded................................................................... T. subrotundata Fabrizi, Dalstein & Ahrens, 2019
38 Dorsal lobe of left paramere 1/3 as long as ventral lobe. Ventral lobe of right paramere almost straight in apical half (lateral view). Apical median phallobasal lamina wider, its dorsal margin slightly concave......... T. matsumotoi Kobayashi, 2017
- Dorsal lobe of left paramere half as long as ventral lobe. Ventral lobe of right paramere almost evenly curved in apical half (lateral view). Apical median phallobasal lamina wider, its dorsal margin slightly convex....................................................................................................... T. bankrang Ahrens, new species
39 Dorsal lobe of left paramere a quarter of its length longer than the ventral one. Right paramere narrower (in lateral view) and half as long as median lamina of phallobase................................................................ 40
- Dorsal lobe of left paramere twice as long as the ventral one.................................................. 41
40 Dorsal lobe of left paramere only little wider than the ventral one, nearly straight in dorsal view. Right paramere bent in an obtuse angle at middle............................................ T. loeiensis Fabrizi, Dalstein & Ahrens, 2019
- Dorsal lobe of left paramere distinctly wider than the ventral one, slightly curved (dorsal view). Right paramere bent in a nearly sharp angle at middle......................................... T. spanglerorum Fabrizi, Dalstein & Ahrens, 2019
41 Dorsal lobe of left paramere distinctly exceeding the median lamina of phallobase. Right paramere wider (in lateral view) and little shorter than median lamina of phallobase........................ T. pailinensis Fabrizi, Dalstein & Ahrens, 2019
- Dorsal lobe of left paramere distinctly shorter than the median lamina of phallobase. Right paramere narrower (in lateral view) and distinctly shorter than median lamina of phallobase................. T. auriculata Fabrizi, Dalstein & Ahrens, 2019
42 Left paramere split into two long and narrow filiform lobes. Ventral lobe of right paramere longer, dorsal lobe weakly curved.......................................................................... T. doisangensis Kobayashi, 2017
- Left paramere simple. Ventral lobe of right paramere short, dorsal lobe strongly curved............................. 43
43 Left paramere moderately long and wide, not exceeding the median ventral lamina of phallobase; convex at apex............................................................. T. sigulianshanica Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Left paramere long and filiform, widely exceeding the median ventral lamina of phallobase; bluntly widened at apex.................................................................. T. curviforceps Fabrizi, Dalstein & Ahrens, 2019
44 Eyes of medium size, ratio diameter/interocular distance ≥ 0.59................................................ 71
- Eyes small, ratio diameter/interocular distance ≤ 0.56........................................................ 45
45 Dorsal surface of body unicoloured...................................................................... 46
- Body blackish brown, pronotum reddish............................ T. rubrithorax Fabrizi, Dalstein & Ahrens, 2019
46 Left paramere simple................................................................................. 52
- Left paramere divided into two lobes at base............................................................... 47
47 Medial phallobasal lamina at least 1/4 of phallobasal length................................................... 48
- Medial phallobasal lamina at maximum 1/10 of phallobasal length...... T. thainguyensis Fabrizi, Dalstein & Ahrens, 2019
48 Left paramere distinctly shorter than the median ventral lamina of phallobase............................................................................................... T. khaosoidaoensis Fabrizi, Dalstein & Ahrens, 2019
- Left paramere (dorsal lobe) at least subequal to median ventral lamina of phallobase............................... 49
49 Dorsal lobe of left paramere as long as the median ventral lamina of phallobase................................... 50
- Dorsal lobe of left paramere twice as long as the median ventral lamina of phallobase.................................................................................................. T. rihai Fabrizi, Dalstein & Ahrens, 2019
50 Dorsal lobe of left paramere short, massive, and robust, circular in cross section. Median phallobasal lamina shortly curved dorsally.................................................... T. nonglomensis Fabrizi, Dalstein & Ahrens, 2019
- Dorsal lobe of left paramere long and narrow, more or less strongly curved (dorsal or lateral view). Median phallobasal lamina straight and rounded at apex............................................................................ 51
51 Dorsal lobe of left paramere longer and filiform (not much thicker than the ventral lobe)............................................................................................... T. nussi Fabrizi, Dalstein & Ahrens, 2019
- Dorsal lobe of left paramere slightly shorter and dorsoventrally flattened (clearly thicker than the ventral lobe)...................................................................................... T. sraeken Ahrens, new species
52 Phallobase in dorsal view only slightly asymmetric. Left and right parameres simple, without two lobes................ 53
- Phallobase in dorsal view strongly asymmetric............................................................. 55
53 Left paramere nearly twice as long as narrow median phallobasal lamina........................................ 54
- Left paramere little longer than large median phallobasal lamina............................... T. laotica (Frey, 1972)
54 Left paramere distinctly longer than phallobase. Right paramere strongly curved ventrally at apex..................................................................................................... T. satura (Brenske, 1899)
- Left paramere slightly shorter than phallobase. Right paramere nearly straight (lateral view)......................................................................................... T. filiforceps Fabrizi, Dalstein &Ahrens, 2019
55 Median lamina of phallobase very short, only one quarter of phallobase length.................................... 59
- Median lamina of phallobase approx. half of phallobase length................................................ 56
56 Robust spines on ventral margin of metatibia subequal in length. Phallobase only little produced at right side......................................................................... T. cattienensis Fabrizi, Dalstein & Ahrens, 2019
- Robust spine at middle of ventral margin of metatibia extremely prolonged and s-shaped, exceeding distal margin of metatibia. Phallobase strongly produced at right side................................................................. 57
57 Median phallobasal lamina wide and blunt at apex, with a dorsal blunt tooth. Left paramere subequal in length with median phallobasal lamina................................................................................... 58
- Median phallobasal lamina narrow and sharply pointed at apex, without dorsal tooth. Left paramere distinctly shorter than median phallobasal lamina...................................... T. margheritae Fabrizi, Dalstein & Ahrens, 2019
58 Median lamina of phallobase short and wider, with an apical dorsal tooth, the basal uncleft portion of the left paramere short.......................................................... T. bansanpakiana Fabrizi, Dalstein & Ahrens, 2019
- Median lamina of phallobase longer and narrower, without an apical dorsal tooth, the basal uncleft portion of the left paramere is much longer.................................................................. T. takakuwai Ahrens, 2022
59 Both parameres long and filiform, curved ventrally at apex............ T. microspinosa Fabrizi, Dalstein & Ahrens, 2019
- Left paramere long and filiform, weakly curved; right paramere short and slim, strongly bent at middle............................................................................. T. microfurcata Fabrizi, Dalstein & Ahrens, 2019
- Parameres of other shape.............................................................................. 60
60 Left paramere short and stout........................................................................... 61
- Left paramere long and narrow, more or less straight (in dorsal view)........................................... 63
61 Dorsal lobe of right paramere after basal third strongly curved (dorsal view). Body evenly reddish to dark brown, dorsally only slightly darker....................................................................................... 62
- Right paramere without dorsal lobe but simple.................... T. doiphukhaensis Fabrizi, Dalstein & Ahrens, 2019
62 Dorsal lobe of right paramere at apex simply pointed (dorsal view)........ T. falciformis Fabrizi, Dalstein & Ahrens, 2019
- Dorsal lobe of right paramere at apex with a sharp hook (dorsal view).................................................................................................. T. pseudoliangheensis Fabrizi, Dalstein & Ahrens, 2019
63 Right paramere more or less straight (ventral view). Dorsal surface blackish, ventral surface reddish brown............. 65
- Right paramere strongly curved. Body evenly reddish to dark brown............................................ 64
64 Right paramere u-shaped at base (ventral view). Metatibia normal, without a long spine at the ventral margin........................................................................................... T. senohi Kobayashi, 2018
- Right paramere strongly curved at base but not u-shaped (ventral view). Ventral metatibial margin at middle with a robust and extremely long, s-shaped terminal spine, which is exceeding distal margin of metatarsomere 1. Distal margin of metatibia deeply truncated ending at middle of metatibial ventral margin...................... T. bartolozzii Ahrens, new species
65 Right paramere at base not split into two lobes, without spines................................................ 66
- Right paramere at base split into two short but widely separated lobes, without spines.............................. 68
- Right paramere at base with divergent spines and a distal separated lobe........................................................................................................ T. phatoensis Fabrizi, Dalstein & Ahrens, 2019
66 Right paramere simply pointed. Left paramere narrow, with blunt ventral lobe..................................... 67
- Right paramere hammer-shaped, with a sharply pointed apical double spine, one directed dorsally, and a larger one ventrally. Left paramere wider, with fine dorsal basal lobe.......................... T. romae Fabrizi, Dalstein & Ahrens, 2019
67 Apical lobe of left paramere narrow. Right paramere inserted only little more basally than the left paramere.................................................................... T. longzhouensis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Apical lobe of left paramere wider. Right paramere inserted much more basally than the left paramere..................................................................................... T. olegi Fabrizi, Dalstein & Ahrens, 2019
68 Ventral metatibial spine normal, distinctly shorter than first metatarsomere. Left paramere moderately long and moderately narrow. Apex of dorsal lobe of right paramere without short setae.............................................. 69
- Ventral metatibial spine extremely elongated, distinctly exceeding first metatarsomere. Left paramere long and narrow, without dorsal subbasal lobe. Apex of dorsal lobe of right paramere with dense short setae.............................................................................................. T. bachmaensis Fabrizi, Dalstein & Ahrens, 2019
69 Left paramere with a short dorsal subbasal lobe. Dorsal lobe of right paramere short.......................................................................................... T. cucphongensis Fabrizi, Dalstein & Ahrens, 2019
- Left paramere without dorsal subbasal lobe................................................................ 70
70 Dorsal lobe of right paramere long................................. T. falciforceps Fabrizi, Dalstein & Ahrens, 2019
- Dorsal lobe of right paramere short................................... T. geiserae Fabrizi, Dalstein & Ahrens, 2019
71 Both parameres with dorsal and ventral lobe............................................................... 72
- One or both parameres simple, without two lobes........................................................... 76
72 Dorsal lobe of right paramere simple, not composed of fine spines............................................. 73
- Dorsal lobe of right paramere composed of fine spines....................................................... 75
73 Dorsal lobe of right paramere directed distally............................................................. 74
- Dorsal lobe of right paramere directed basally....................... T. ululalatensis Fabrizi, Dalstein & Ahrens, 2019
74 Dorsal lobe of left paramere as long as ventral one.................. T. fikaceki Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Dorsal lobe of left paramere much shorter than ventral one...................... T. univestris Ahrens & Fabrizi, 2016
- Dorsal lobe of left paramere much longer than ventral one................................ T. miniatula (Moser, 1915)
75 Dorsal lobe of right paramere shorter, less than 1/3 as long as phallobase............. T. chiangdaoensis Kobayashi, 2017
- Dorsal lobe of right paramere longer, half as long as phallobase............... T. kollae Fabrizi, Dalstein & Ahrens, 2019
76 Both parameres simple, without two lobes................................................................. 77
- One of parameres complex, with two lobes................................................................ 83
77 Right paramere distinctly wider (dorsal view) than the left one................................................ 78
- Right paramere as wide as (dorsal view) the left one......................................................... 79
78 Dorsolateral tooth at basal quarter of right paramere, right paramere narrower (lateral view)................................................................................. T. damaidiensis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Dorsolateral tooth at basal third of right paramere, right paramere wider (lateral view)........................................................................................ T. semidamadiensis Fabrizi, Dalstein & Ahrens, 2019
79 Left paramere one third as long as phallobase. Median lamina of phallobase not widened at apex..................... 80
- Left paramere longer.................................................................................. 81
8 Left and right paramere subequal in length. Rigth paramere almost straight (lateral view)................................................................................... T. xiengkhouangensis Fabrizi, Dalstein & Ahrens, 2019
- Left paramere almost twice as long as right one. Rigth paramere strongly bent at middle (lateral view)....................................................................................... Tetraserica hongheensis Ahrens, 2021
81 Left paramere as long as phallobase...................................................................... 82
- Left paramere half as long as phallobase......................... T. petrpacholatkoi Fabrizi, Dalstein & Ahrens, 2019
82 Median lamina of phallobase strongly widened and truncate at apex........ T. constanti Fabrizi, Dalstein & Ahrens, 2019
- Median lamina of phallobase not widened at apex.................. T. vientianeensis Fabrizi, Dalstein & Ahrens, 2019
83 Right paramere simple, left one with two lobes............................................................. 84
- Left paramere simple, right one with two lobes............................................................. 89
84 Right paramere basiventrally strongly widened towards apex, at base with a narrow long basal lobe............................................................................ T. yaoquensis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Right paramere evenly narrowed towards apex............................................................. 85
85 Dorsal surface dark brown............................................................................. 87
- Dorsal surface yellowish brown......................................................................... 86
86 Ventral lobe of left paramere wider, stronger curved ventrally. Dorsal lobe of left paramere bluntly widened before apex................................................................. T. shanensis Fabrizi, Dalstein & Ahrens, 2019
- Ventral lobe of left paramere narrower, nearly straight (lateral view). Dorsal lobe of left paramere nearly evenly narrowed towards apex................................................ T. semishanensis Fabrizi, Dalstein & Ahrens, 2019
87 Left paramere with a dorsal lobe distant from base.......................................................... 88
- Left paramere with dorsal lobe at base, lobe robust (nearly half as long as paramere) and at apex convex............................................................................. T. breviforceps Fabrizi, Dalstein & Ahrens, 2019
88 Left paramere narrower, with a short fine dorsal lobe before the middle...................................................................................................... T. trilobiforceps Fabrizi, Dalstein & Ahrens, 2019
- Left paramere shorter and stouter, with a short fine dorsal lobe behind the middle.......................................................................................... T. phukradungensis Fabrizi, Dalstein & Ahrens, 2019
89 Left paramere long, slender............................................................................ 91
- Left paramere shorter, stouter, almost straight.............................................................. 90
90 Left paramere slenderer, weakly bent externally in apical quarter...................... T. qifengshanensis Ahrens, 2021
- Left paramere stouter, almost straight...................... T. wangtongensis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
91 Left paramere bent externally. Distal lobe of right paramere short.............................................. 92
- Left paramere bent straight, split shortly before apex. Distal lobe of right paramere long, more than half as long as phallobase.................................................................. T. jakli Fabrizi, Dalstein & Ahrens, 2019
92 Basal lobe of right paramere short, without spines. Insertion of right parameres lateral................................................................................... T. changjiangensis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Basal lobe of right paramere moderately long, with trichome-like spines. Insertion of right parameres displaced dorsally... 93
93 Left paramere half as long as phallobase........................... T. setuliforceps Fabrizi, Dalstein & Ahrens, 2019
- Left paramere as long as phallobase........................... T. parasetuliforceps Fabrizi, Dalstein & Ahrens, 2019
94 Right paramere basally with brush of robust trichome-like spines............................................... 95
- Right paramere without brush of spines.................................................................. 116
95 Left paramere composed of two lobes..................................................................... 96
- Left paramere simple................................................................................ 101
96 Left paramere long, as long as the ventral distal phallobasal process............................................ 97
- Left paramere short and trifid, 1/3 as long as the ventral distal phallobasal process................................ 100
97 Ventral lobe of right paramere abruptly and strongly widened at apex, dorsal lobe of right paramere obsolete but with dense trichomes.......................................................................................... 98
- Ventral lobe of right paramere not widened at apex, dorsal lobe of right paramere moderately long and narrow, composed of fine spines.................................................. T. pluriuncinata Fabrizi, Dalstein & Ahrens, 2019
98 Dorsal lobe of right paramere basally with a distinct and sharp hook. Ventral lobe of left paramere wide and flattened. Ventral lobe of right paramere with a smaller apical widening................................ T. weigeli Ahrens, new species
- Dorsal lobe of right paramere basally plain, without hook. Ventral lobe of left paramere narrow. Ventral lobe of right paramere with a large apical widening............................................................................ 99
99 Ventroapical lobe of right paramere narrower, ventral lobe of left paramere little shorter than the dorsal one.................................................................... T. allochangshouensis Fabrizi, Dalstein & Ahrens, 2019
- Ventroapical lobe of right paramere wider, ventral lobe of left paramere one third as long as the dorsal one................................................................... T. changshouensis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
100 Median lamina of phallobase with a small dorsal preapical tooth. Dorsal lobe of left parameres and median lamina of phallobase distinctly longer than phallobase.......................................... T. siantarensis (Moser, 1922) (Sumatra)
- Median lamina of phallobase without dorsal preapical tooth. Dorsal lobe of left parameres and median lamina of phallobase as long as phallobase.......................................... T. feresiantarensis Fabrizi, Dalstein & Ahrens, 2019
101 Left paramere with small lateral basal tooth....................................................................................................................... T. linaoshanica Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Left paramere without small lateral basal tooth............................................................ 102
102 Left paramere split in two filiform branches behind anterior third............................................. 103
- Left paramere simple................................................................................ 108
103 Median phallobasal lamina convex or simply pointed at apex................................................. 104
- Median phallobasal lamina bifurcate at apex....................... T. quadrifurcata Fabrizi, Dalstein & Ahrens, 2019
104 Filiform branches of left paramere long, at least approx. one third of paramere length............................. 105
- Filiform branches of left paramere very short, much less than one length of paramere length........................ 107
105 Basal portion of right paramere only slightly elevated and half as high as distal portion of the paramere. Left paramere with a blunt tooth on dorsal margin........................................................................... 106
- Right paramere with a convex basal lobe subequal in length to apical portion of paramere. Left paramere without blunt tooth on dorsal margin.................................................... T. phamanhi Pham & Ahrens, new species
106 Filiform branches of left paramere approx. one third of paramere length. Median phallobasal lamina most of its distal part narrow................................................... T. mengeana Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Filiform branches of left paramere approx. two third of paramere length. Median phallobasal lamina evenly narrowed towards apex....................................................... T. allomengeana Fabrizi, Dalstein & Ahrens, 2019
107 Distal lobe of right paramere long and robust, strongly curved upward (lateral view), with a strong subapical ventral tooth................................................................ T. finociliata Fabrizi, Dalstein & Ahrens, 2019
- Distal lobe of right paramere short, weakly curved (lateral view), without ventral tooth......................................................................................... T. appendiculata Fabrizi, Dalstein & Ahrens, 2019
108 Left paramere distinctly longer than phallobase............................................................ 109
- Left paramere as long as phallobase, evenly curved....................... T. sapana Fabrizi, Dalstein & Ahrens, 2019
109 Left paramere bent twice or entirely curved............................................................... 114
- Left paramere in basal half straight..................................................................... 110
110 Left paramere before apex with tiny tooth or tooth-like process............................................... 111
- Left paramere before apex without tiny tooth................... T. konchurangensis Fabrizi, Dalstein & Ahrens, 2019
111 Median lamina of phallobase straight and strongly narrowed after basal the third................................. 112
- Median lamina of phallobase distinctly curved and evenly narrowed from base to apex.......................................................................................... T. namnaoensis Fabrizi, Dalstein & Ahrens, 2019
112 Median lamina of phallobase distinctly shorter than left paramere, simply pointed, slightly rounded at apex............ 113
- Median lamina of phallobase approx. as long as left paramere, slightly bifurcate at apex. Preapical tooth of left paramere dorsally and duplicate............................................... T. smetsi Fabrizi, Dalstein & Ahrens, 2019
113 Preapical tooth of left paramere laterally. Left paramere strongly curved................................................................................................. T. shangsiensis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Preapical tooth of left paramere dorsally, transformed into a filiform process that is rounded at apex. Left paramere nearly straight............................................................................ T. gressitti (Frey, 1972)
114 Dorsal lobe of right paramere very small................................................................. 115
- Dorsal lobe of right paramere large, nearly as long as ventral lobe......................... T. tonkinensis (Moser, 1908)
115 Left paramere bent twice. Median lamina of phallobase in apical half distinctly narrowed.................................................................................... T. xichouensis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Left paramere nearly uniformly curved. Median lamina of phallobase in apical half not narrowed............................................................................... T. paratonkinensis Fabrizi, Dalstein & Ahrens, 2019
116 Right paramere simple, not composed of two lobes......................................................... 117
- Right paramere composed of two lobes.................................................................. 138
117 Left paramere at base simple.......................................................................... 125
- Left paramere at base composed of two lobes............................................................. 118
118 Right paramere at least subequal in length to phallobase, without apical hook ventrally............................ 119
- Right paramere approx. one third as long as phallobase, or shorter............................................. 122
- Right paramere half as long as phallobase. Left paramere longer than phallobase... T. koi Fabrizi, Dalstein & Ahrens, 2019
119 Ventral distal spine of metatibia inserted at apex of metatibia and much shorter than the metatarsomere 1. Basal lobe of left paramere ¼ as long as ventral lobe...................................................................... 120
- Ventral distal spine of metatibia inserted shortly behind middle of ventral margin of metatibia and longer than the long metatarsomere 1..................................................................................... 121
120 Right paramere slightly widened towards apex.................... T. longipenis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Right paramere evenly narrowed towards apex. Dorsal lobe of left paramere is at apex slightly hooked dorsally............................................................................ T. fabriziae Liu, Li & Ahrens, new species
121 Basal lobe of left paramere half as long as ventral lobe............................ T. angkhangensis Kobayashi, 2017
- Basal lobe of left paramere as long as ventral lobe...................... T. giulianae Fabrizi, Dalstein & Ahrens, 2019
122 Phallobase at right side not strongly produced. Right paramere with a small apical hook ventrally. Left paramere split much behind base into two lobes............................................................................ 123
- Phallobase at right side strongly produced. Left paramere split at base into two lobes.............................. 124
123 Left paramere split behind middle into two filiform branches. Distal portion of right paramere much shorter than basal part............................................................ T. tanahrataensis Fabrizi, Dalstein & Ahrens, 2019
- Left paramere split more basally (at 1/3 of its length) into two long, filiform branches. Distal portion of right paramere (behind median bent) as long as basal portion........................................... T. yongbelar Ahrens, new species
124 Right paramere without small apical hook. Dorsal lobe of left paramere small............ T. maerimensis Kobayashi, 2018
- Right paramere with a small apical hook. Dorsal lobe of left paramere half as long as ventral lobe............................................................................. T. angkorthomensis Fabrizi, Dalstein & Ahrens, 2019
125 Left paramere over its entire length not split, but simple..................................................... 128
- Left paramere split behind base into two long filiform branches............................................... 126
126 Left paramere split behind basal third. Right paramere short and curved...................................................................................................... T. dongnaiensis Fabrizi, Dalstein & Ahrens, 2019
- Left paramere split in apical half. Right paramere long and straight............................................ 127
127 Right paramere split into two narrow branches at apical quarter........................... T. sejugata (Brenske, 1898)
- Right paramere split into two narrow branches at basal third............. T. allosejugata Fabrizi, Dalstein & Ahrens, 2019
128 Left paramere more or less narrow, at middle distinctly narrower than apex of phallobase (lateral view)............... 129
- Left paramere wide over its entire length, at middle nearly as wide as apex of phallobase (lateral view).................................................................................. T. fulleri Fabrizi, Dalstein & Ahrens, 2019
129 Left paramere strongly bent at base..................................................................... 133
- Left paramere straight at base.......................................................................... 130
130 Left paramere straight in basal half distinctly wider than in apical half. Right paramere half as long as phallobase...................................................................... T. desalvazzai Fabrizi, Dalstein & Ahrens, 2019
- Left paramere straight in basal half only little wider than in apical half. Right paramere at maximum one third as long as phallobase......................................................................................... 131
131 Median lamina of phallobase at apex curved dorsally. Basis of left paramere not extended ventrally.............................................................................. T. angkorwatensis Fabrizi, Dalstein & Ahrens, 2019
- Median lamina of phallobase at apex straight. Basis of left paramere strongly extended ventrally..................... 132
132 Right paramere much less than one third as long as left paramere..... T. pseudoruiliensis Fabrizi, Dalstein & Ahrens, 2019
- Right paramere one third as long as left paramere........................................ T. gestroi (Brenske, 1898)
133 Left paramere bent downward basally. Median phallobasal lamina simply pointed................................. 134
- Left paramere bent upward basally. Median phallobasal lamina widened and sharply truncate at apex...................................................................................... T. vari Fabrizi, Dalstein & Ahrens, 2019
134 Median lamina of phallobase straight. Phallobase at right side not strongly produced.............................. 135
- Median lamina of phallobase evenly curved ventrally. Phallobase at right side strongly produced........................................................................................ T. infida Fabrizi, Dalstein & Ahrens, 2019
135 Ventral terminal spine of metatibia slightly shorter than first metatarsomere..................................... 136
- Ventral terminal spine of metatibia distinctly longer than first metatarsomere. Right paramere strongly bent at middle (lateral view)........................................................ T. spinotibialis Fabrizi, Dalstein & Ahrens, 2019
136 Right paramere moderately bent at middle (lateral view).................................................... 137
- Right paramere nearly straight (lateral view)....................... T. semiruiliensis Fabrizi, Dalstein & Ahrens, 2019
137 Left paramere longer (compared to the length of phallobase) and narrow (lateral view). Apical portion of right paramere longer (distal to the strong bent at middle) shorter than basal portion........ T. ruiliensis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Left paramere distinctly shorter (compared to the length of phallobase) and more robust (lateral view). Apical portion of right paramere longer (distal to the strong bent at middle), subequal in length to basal portion.............................................................................................. T. gialaiensis Pham & Ahrens, new species
138 Left paramere simple................................................................................. 140
- Left paramere composed of two lobes.................................................................... 139
139 Right side of phallobase strongly produced. Dorsal lobe of left paramere as long as ventral one..................................................................................... T. soppongana Fabrizi, Dalstein & Ahrens, 2019
- Right side of phallobase not strongly produced. Dorsal lobe of left paramere short, distinctly shorter than ventral one.... 146
140 Dorsal lobe of right paramere wide, with sickle-shaped, large apical hook................................................................................................. T. tianchiensis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Dorsal lobe of right paramere narrow, evenly curved or straight, and sharply pointed.............................. 141
141 Left paramere filiform. Right paramere much less than half as long as left paramere....................................................................................... T. jinghongensis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Left paramere elongate and robust...................................................................... 142
142 Left paramere with a large triangular dorsomedian extension................................................. 143
- Left paramere without large dorsomedian extension........................................................ 144
143 Right paramere slightly more than half as long as left paramere. Split between lobes of right parameres deep, dorsal lobe as long as ventral lobe.................................................. T. veliformis Fabrizi, Dalstein & Ahrens, 2019
- Right paramere half as long as left paramere. Dorsal lobe of right paramere distinctly shorter than ventral lobe...................................................................... T. umphangensis Fabrizi, Dalstein & Ahrens, 2019
144 Right paramere a quarter as long as left paramere. Split between lobes of right parameres little deep, dorsal lobe reduced in size....................................................................... T. latefemorata Kobayashi, 2017
- Right paramere one third as long as left paramere, dorsal lobe large, as large as ventral one.............................................................................................. T. yucheni Liu, Li & Ahrens, new species
- Right paramere half as long as left paramere. Split between lobes of right parameres deep, dorsal lobe not reduced in size..................................................................................................... 145
145 Left paramere at middle narrow (lateral view), only little longer than median phallobasal lamina................................................................................. T. bolavensensis Fabrizi, Dalstein & Ahrens, 2019
- Left paramere at middle distinctly widened, distinctly longer than median phallobasal lamina....................................................................................... T. nakaiensis Fabrizi, Dalstein & Ahrens, 2019
146 Dorsal lobe of right paramere triangular and short, sharply pointed.................................................................................................... T. menglongensis Liu, Fabrizi, Bai, Yang & Ahrens, 2014
- Dorsal lobe of right paramere convexly widened and elongate......... T. ruiliana Liu, Fabrizi, Bai, Yang & Ahrens, 2014
147 Punctation of elytra very dense, concentrated exclusively along striae, intervals strongly convex. Dorsal margin of metatibia longitudinally convex................................................................................ 156
- Punctation of elytra dense, not exclusively concentrated along striae; intervals weakly convex to flat. Dorsal margin of metatibia sharply carinate..................................................................................... 148
148 Antennomeres of antennal club evenly long, first segment at maximum 1/10 of club length, shorter.................. 149
- First segment of antennal club distinctly shorter (by at least 1/4 of club length), club sometimes only with three antennomeres.......................................................................... T. ferrugata (Blanchard, 1850)
149 Metatibia shorter, ratio width/length> 1/3.0.............................................................. 150
- Metatibia longer, ratio width/length <1/3.2............................................................... 152
150 Dorsal lobe of right paramere with a narrow comb-like basal lobe...................... T. rungbongensis Ahrens, 2004
- Dorsal lobe of right paramere simply pointed, without a narrow comb-like basal lobe............................. 151
151 Dorsal lobe of right paramere well separated and subequal in length to ventral lobe................ T. impar Ahrens, 2004
- Dorsal lobe of right paramere adjacent, rudimentary, and much shorter (1/5 of its length) than ventral lobe.............................................................................................. T. pellingana Ahrens, 2021
152 Articulation of right paramere displaced dorsally. Dorsal lobe of right paramere broad, apically split abruptly into many long spikes...................................................................... T. brahmaputrae Ahrens, 2004
- Articulation of right paramere not displaced. Dorsal lobe of right paramere narrow, without multiple apical spikes...... 151
153 Eyes small, ratio diameter/interocular width <0.5. Antennal club short, as long as remaining antennomeres combined. Sides of pronotum light brown.................................................... T. rufimargo Ahrens & Fabrizi, 2016
- Eyes moderately large, ratio diameter/interocular width> 0.6. Antennal club longer, at least 1.2 times as long as remaining antennomeres combined.............................................................................. 154
154 Right paramere composed of two distinct lobes................................ T. univestris Ahrens & Fabrizi, 2016
- Right paramere composed of one distinct lobe............................................................ 155
155 Right paramere in lateral view spherical, with numerous sharp spikes on dorsal margin. Left paramere not displaced dorsally, its dorsal lobe extremely long, without apical hook................................ T. bendai Ahrens & Fabrizi, 2016
- Right paramere in lateral view elongate, without spikes on dorsal margin. Left paramere displaced dorsally, its dorsal lobe with a strong apical hook...................................................... T. uncinata Ahrens & Fabrizi, 2016
156 Parameres nearly equally long......................................................................... 157
- Left paramere much longer than right........................................ T. crenatula Ahrens & Fabrizi, 2009
157 Metatibia shorter and wider, ratio length/width: 1/2.96. Left paramere shorter than right. Body short oval, <6 mm ...................................................................................... T. disoccupata Ahrens, 2004
- Metatibia narrower, ratio length/width <1/3.2. Parameres highly similar in length. Body elongate,> 7.0 mm........... 158
158 Left paramere at apex with external tooth............................................. T. schneideri Ahrens, 2004
- Left paramere at apex without external tooth..................................... T. hilaris Ahrens & Fabrizi, 2009
description: Published as part of Ahrens, Dirk, Lukic, Daniel, Pham, Phu, Li, Wei & Liu, Wangang, 2023, Tetraserica Ahrens, 2004 of continental Southeast Asia: new records, new species and an updated key to species (Coleoptera: Scarabaeidae: Sericinae: Sericini), pp. 451-486 in Zootaxa 5374 (4) on pages 471-478, DOI: 10.11646/zootaxa.5374.4.1, http://zenodo.org/record/10158722