Serica MacLeay, 1819

Ahrens, Dirk, Fabrizi, Silvia, Bai, Ming & Liu, Wangang, 2022, Taxonomic revision of Serica MacLeay, 1819 (sensu lato) from China and adjacent areas (Coleoptera: Scarabaeidae: Melolonthinae: Sericini), with updates on Nipponoserica Nomura, 1972, Zootaxa 5186 (1), pp. 1-83 : 6-8

Serica MacLeay, 1819

Serica MacLeay, 1819: 146 .

Trichoserica Reitter, 1896: 181

(type species by original designation: Trichoserica fulvopubens Reitter, 1896 ); synonymized by Nomura 1972: 110.

Ophthalmoserica Brenske, 1897: 395

(type species by subsequent designation: Serica thibetana Brenske, 1897: 395 ; Ahrens 1999); synonymized by Nomura 1972: 110.

Podoserica Breit, 1912: 202

(type species by monotypy: Podoserica reitteri Breit, 1912: 202 ); synonymized by Ahrens 2005: 3.

Type species: Serica brunnea (Linnaeus, 1758) (by monotypy).

Taxonomic revision and new species

Key to subgenera and species groups of Serica in framework of the genera of Sericini with tri-lamellate antennal club occurring in continental South-East Asia (♂♂):

1 Base of pronotum with marginal line. Hypomeron not carinate...................... Archaehomaloplia Nikolajev, 1982

- Base of pronotum without marginal line.................................................................... 2

2 Protibia with three teeth................................................................................ 3

- Protibia with two teeth................................................................................. 4

3 Body unicolored: blackish, brown or reddish brown........................................ Maladera sinica group

- Body bicolored. Antennal club in male composed of four antennomeres........................ Trioserica Moser, 1922

4 Hypomeron carinate................................................................................... 8

- Hypomeron not carinate................................................................................ 5

5 Antennal club in male composed of three antennomeres....................................................... 6

- Antennal club in male composed of four antennomeres................................... Tetraserica Ahrens, 2004

6 Body elongate, dark or light brown, mostly dull. Antennal club in male long. Apex of metatibia shallowly or sharply truncate.................................................................... 7

- Body short, yellowish brown, shiny...................................................... Maladera haba group

7 Dorsal surface with at least a few short setae on pronotum and elytra. .......................... Serica MacLeay, 1819

- Dorsal surface generally glabrous, rarely with a few short setae on pronotum and elytra. ..................................................................................................... Nipponoserica Nomura, 1973 (part)

8 Antennal club in male composed of three antennomeres....................................................... 9

- Antennal club in male composed of more than three antennomeres........other multi-lamellate genera (not included here) 2‡

9 Legs narrow and long (ratio width/length: 1/3.3–4.6)........................................................ 10

- Legs not narrow and short to moderately long (ratio width/length: 1/2.5–3)...................................... 12

10 Parameres asymmetrical. Metacoxa glabrous except lateral or microscopic setae................................... 11

- Parameres symmetrical. Metacoxa evenly covered with adjacent fine setae.................... Xenoserica Ahrens, 2005

11 Dorsal surface almost completely glabrous..................................... Nipponoserica Nomura, 1973 (part)

- Dorsal surface generally with numerous setae and widely dull. ................ Serica MacLeay, 1819 (sensu lato) (part)

12 Metafemur without serrated line adjacent to the anterior margin............................................... 13

- Metafemur with a serrated line adjacent to the anterior margin..................................................................................................... Maladera Mulsant & Rey, 1871 , Amiserica Nomura, 1974 *

13 Mesostermum not produced anteriorly between mesocoxae................................................... 14

- Mesostermum produced anteriorly between mesocoxae, protuding....................... Hoplomaladera Nomura, 1974

14 Apex of metatibia sharply truncate at interior apex near tarsal articulation.......................................... .................................................. Maladera (subgenus Hemiserica Brenske, 1894 ) (part, India)

- Apex of metatibia bluntly truncate or concavely emarginate at interior apex near tarsal articulation.................... 15

15 Dorsal posterior margin of metafemur serrate. Legs generally slender........................................... 16

- Dorsal posterior margin of metafemur smooth................................ Maladera Mulsant & Rey, 1871 (part) 4*

16 Parameres narrow and symmetric....................................................................... 17

- Parameres asymmetric................................................................................ 18

17 Body reddish brown and shiny. Metatarsi not carinate laterally. Carina of hypomeron not ventrally produced.......................................................................................... Maladera brunnescens group

- Body dark brown, dull. Metatarsi carinate laterally. Carina of hypomeron ventrally produced............................................................................................... Gastromaladera Nomura, 1973 ( Japan)

‡ For further details, see Liu et al. (2019)

* For further details, see Fabrizi et al. (2021)

18 Anterior angles of pronotum not produced, obsolete. Dorsal surface with dense pilosity, often composed by white scale-like setae.......................................................................... Pachyserica Brenske, 1897

- Anterior angles of pronotum not obsolete, blunt to sharp..................................................... 19

19 Hypomeron weakly carinate. ........................................... Serica MacLeay, 1819 (sensu lato) (part)

- Hypomeron distinctly carinate.......................................................................... 20

20 Mentum convexly elevated anteriorly..................................................................... 21

- Mentum flat, with a semi-circular ridge anteriorly................................... Trichomaladera Nomura, 1974

21 Dorsal and ventral surface densely setose. (Antennal club generally longer then remaining antennomeres combined.)..... 22

- Dorsal and ventral surface sparsely setose. (Antennal club as long as or shorter than remaining antennomeres combined.)........................................................................ Maladera Mulsant & Rey, 1871 (part) *

22 Dorsal pilosity simple, dorsal surface always shiny........................................ Paraserica Reitter, 1896

- Dorsal pilosity double, composed of long and short setae, dorsal surface always at largest extent dull...................................................................................... Serica MacLeay, 1819 (sensu lato) (part)

Key to the species of Serica (sensu lato) of continental South-East Asia (♂♂):

1 Dorsal surface unicolored............................................................................... 2

- Dorsal surface, particularly elytra, multi-colored............................................................ 25

2 Dorsal surface brown and glabrous........................................................................ 3

- Dorsal surface darker and generally with erect setae on dorsal surface........................................... 12

3 Body reddish to dark brown. Antennal club at least twice as long as remaining antennomeres combined................. 4

- Body yellowish brown.Antenna with 9 antennomeres; Antennal club at maximum 1.5 times as long as remaining antennomeres combined........................................................................................... 8

4 Metatibia long and narrow, ratio width/ length: 1/ 4.2. Antenna with 10 antennomeres............................... 5

- Metatibia long and little wider, ratio width/ length: 1/ 3.7...................................................... 6

5 Metatibia long and narrow, ratio width/ length: 1/ 4.2. Apex of the phallobase strongly bent (lateral view).............................................................................................. S. solivaga ( Brenske, 1898)

- Metatibia moderately long and wide, ratio width/ length: 1/3.2. Apex of the phallobase more straight (lateral view).................................................................. S. mengsonana Ahrens, Fabrizi & Liu , new species

6 Antenna with 9 antennomeres. Antennal club 5 times as long as remaining antennomeres combined. Basal lobe of the right paramere wide and large. ...................................................... S. fashengi Liu & Ahrens, 2014

- Antenna with 10 antennomeres. Antennal club 4 times as long as remaining antennomeres combined. Basal lobe of the right paramere narrower.................................................................................... 7

7 Right paramere narrower, without blunt dorsomedian extension, sharply pointed towards apex (lateral view). Dorsal lobe of left paramere reflexed externally................................................ S. falcifera Ahrens & Fabrizi, 2009

- Right paramere wider, with a blunt dorsomedian extension, moderately pointed towards apex (lateral view). Dorsal lobe of left paramere reflexed internally. ........................................................ S. segregata Arrow, 1946

8 Dorsal surface dull. Phallobase at right side with an apical lateral apophyses laterally............................... 9

- Dorsal surface shiny. Phallobase at right side without apical lateral apophyses laterally............................... ............................................................. S. longwan Ahrens, Fabrizi & Liu , new species

9 Basal lobe of left paramere extended only basomedially...................................................... 10

- Basal lobe of left paramere extended basomedially and distally................................ S. longula Frey, 1972

10 Basal lobe of left paramere strongly curved and directed distally...... S. tiammushan Ahrens, Fabrizi & Liu , new species

- Basal lobe of left paramere directed medially.............................................................. 11

11 Antennal club distinctly longer than remaining antennomeres combined. Right paramere moderately angled dorsally.................................................................. S. daqiaoana Ahrens, Fabrizi & Liu , new species

- Antennal club distinctly as long as remaining antennomeres combined. Right paramere strongly angled dorsally..................................................................... S. jiankouensis Ahrens, Fabrizi & Liu , new species

12 Labroclypeus distinctly emarginated medially.............................................................. 13

- Labroclypeus weakly emarginated medially............................................................... 15

13 Dorsal surface shiny. Aedeagus in apical half dorsoventrally flattened........................... S. excisa ( Frey, 1972)

- Dorsal surface dull. Aedeagus in apical half almost spherical in cross-section..................................... 14

14 Labroclypeus deeply emarginated medially. Lateral margin of pronotum slightly concave........................................................................................ S. shiduensis Ahrens, Fabrizi & Liu , new species

- Labroclypeus moderately emarginated medially. Lateral margin of pronotum straight. ........... S. klapperichi Frey, 1972

15 Body more oval, pronotum subequal a third of elytral length................................................... 16

- Body elongate, pronotum subequal a quarter of elytral length................................................. 17

16 Antennal club in male long, three times as long as remaining antennomeres combined. Parameres with distinct basal lobes... .................................................... S. huangbaiyuanensis Ahrens, Fabrizi & Liu , new species

- Antennal club in male short, as long as remaining antennomeres combined. Parameres without distinct basal lobes................................................................ S. guangnanensis Ahrens, Fabrizi & Liu , new species

17 Parameres at maximum almost subequal to half phallobase length. Species from Northern Myanmar.. S. lupina Arrow, 1946

- Parameres distinctly shorter............................................................................ 18

18 Parameres at maximum subequal to one third of phallobase length.............................................. 19

- Parameres at maximum subequal to a quarter or less of phallobase length........................................ 21

19 Right paramere curved ventrally (lateral view), without preapical lateral tooth.................................... 20

- Right paramere straight (lateral view), with sharp and distinct preapical lateral tooth.................................................................................................. S. yini Ahrens, Fabrizi & Liu , new species

20 Dorsal surface of body densely setose. Left paramere more or less straight, distinctly shorter than right one...................................................................... S. baishuitaiensis Ahrens, Fabrizi & Liu , new species

- Dorsal surface of body sparsely setose. Left paramere strongly curved and bent ventrally below ventral portion of phallobase, almost as long as right paramere. ................................. S. paralupina Ahrens, Fabrizi & Liu , new species

21 Apex of right paramere sharply pointed............................ S. gaoligong Ahrens, Fabrizi & Liu , new species

- Apex of right paramere rounded or bluntly truncate......................................................... 22

22 Dorsal pilosity dense. Right paramere almost straight........................................................ 23

- Dorsal pilosity sparse................................................................................. 24

23 Left paramere weakly curved...................................... S. nanhua Ahrens, Fabrizi & Liu , new species

- Left paramere strongly curved..................................... S. longipes Ahrens, Fabrizi & Liu , new species

24 Right paramere strongly curved. Left paramere wide, flattened in cross section over almost two thirds of its entire length. ............................................................. S. allolongipes Ahrens, Fabrizi & Liu , new species

- Right paramere weakly curved. Left paramere narrow and sickle-shaped, almost circular in cross section over almost its entire length. ................................................... S. paralongipes Ahrens, Fabrizi & Liu , new species

25 Parameres inserted strongly asymmetric, left paramere much more basally than the right one......................... 26

- Phallobase rather symmetric, parameres inserted almost at the same level........................................ 34

26 Right paramere with a narrow basal lobe directed medially................................................... 28

- Right paramere without a narrow basal lobe directed medially. Phallobase narrowed towards apex (dorsal view)......... 27

27 Phallobase concavely excised dorsoapically.............................................. S. dathei Ahrens, 2005

- Phallobase with a process-like median extension at mesoapical margin. Antennal club 1.2 times as long as remaining antennomeres combined. .......................................... S. dissimillima Ahrens, Fabrizi & Liu , new species

28 Phallobase truncate apex (dorsal view), its dorsal margin straight. Antennal club 1.5 times as long as remaining antennomeres combined........................................................................................... 29

- Phallobase concavely excised dorsoapically............................................................... 30

29 Left paramere more than half as long as the right. ....................... S. zhenba Ahrens, Fabrizi & Liu , new species

- Left paramere less than half as long as the right...................................... S. nanjiangana Ahrens, 2005

30 Right paramere very long and narrow, sharply pointed. Left paramere without any lateral tooth.. S. trapezicollis Ahrens, 2005

- Right paramere moderately long and wider, rounded at apex................................................... 31

31 Left paramere ca one third of the length of the right one...................................................... 32

- Left paramere more than half of the length of the length of the right one......................................... 33

32 Right paramere abruptly narrowed behind middle. Left paramere dorsoventrally not flattened. ......................................................................................... S. jani Ahrens, Fabrizi & Liu , new species

- Right paramere evenly narrowed towards apex. Left paramere dorsoventrally flattened................................ ............................................................. S. jaroslavi Ahrens, Fabrizi & Liu , new species

33 Left paramere in distal portion with a lateral tooth........................................ S. albisetis Ahrens, 2005

- Left paramere without lateral apical tooth, but its left paramere having its dorsomedial tooth at basal third....................................................................... S. shengtangshan Ahrens, Fabrizi & Liu , new species

34 Aedeagus robust, with a long double dorsal phallobasal process which exceeds almost parameres.... S. adspersa Frey, 1972

- Aedeagus elongate, without dorsal phallobasal process, but simply concavely emarginate between parameres........... 35

35 Elytral surface with moderately dense to dense setae........................................................ 36

- Elytral surface with sparse setae......................................................................... 37

36 Pilosity of dorsal surface double, with at least two types of setae. Elytra with a large dark spot before apex............... ........................................................................ S. nigroguttata group (see below)

- Pilosity of dorsal surface simple, with one type of setae only. Elytra without dark spot before apex. Metasternum anteriorly abruptly and strongly elevated. ................................................... S. velutina group (see below)

37 Parameres both subdivided into a long dorsal and ventral lobe. Metafemur, submarginal serrated line beside anterior margin present or absent............................................... Serica (subgenus Taiwanoserica Nomura, 1974 )

- Parameres not subdivided into a long dorsal and ventral lobe, or only one of both subdivided into a long dorsal and ventral lobe. Metafemur, submarginal serrated line beside anterior margin always absent...................................... 38

38 Pronotum almost glabrous, with a few adpressed setae on posterior disc; surface evenly plane, in anterior part shiny, posteriorly dull. Frons shiny in anterior half..................................... S. ziqingi Ahrens, Fabrizi & Liu , new species

- Pronotum densely setose on anterior disc, surface with shallow transverse impressions, entirely dull or iridescent shiny. Frons entirely dull......................................................................................... 39

39 Pronotum narrow. Body more elongate. Parameres shorter, left one, half as long as the right ............................ ................................................................. S. jirii Ahrens, Fabrizi & Liu , new species

- Pronotum more transverse. Body oblong and less convex. Parameres long, both of the same length..................... ............................................................. S. pangwa Ahrens, Fabrizi & Liu , new species