Maladera fistulosa (Brenske, 1898)

Ranasinghe, Sasanka, Eberle, Jonas, Athukorala, Namal, Benjamin, Suresh P. & Ahrens, Dirk, 2022, New species of Sericini from Sri Lanka (Coleoptera, Scarabaeidae). Part II, European Journal of Taxonomy 821 (1), pp. 57-101 : 88-91

Updated and corrected key to species of the Maladera fistulosa group (♂♂)

1. Pronotum glabrous on disc, sometimes a few sparse setae on lateral pronotal disc. Anterior marginal line of pronotum widely incomplete medially .................................................................................. 2

– Pronotum densely setose ................................................................................................................. 13

2. Apical margin of metacoxa slightly concave, glabrous. Metatibia basally with a longitudinal serrated line .................................................................................................................................................... 3

– Apical margin of metacoxa straight or convex. Metatibia basally without a longitudinal serrated line .................................................................................................................................................... 5

3. Metatibia more stout (ratio width/length> 1/3.2) ............................................................................ 4

– Metatibia more slender (ratio width/length <1/3.7). Antennal club slightly longer than the remaining antennomeres together. Apex of aedeagus more strongly narrowed apically, median hook absent ventrally ............................................................................... M. hortonensis Fabrizi & Ahrens, 2014

4. Metatibia ratio width/length: 1/2.8. Antennal club 1.2 times as long as remaining antennomeres together. Apex of aedeagus apically evenly narrowed and dorsoventrally compressed ..................... ................................................................................................. M. lindulana Fabrizi & Ahrens, 2014

– Metatibia ratio width/length: 1/3.2. Antennal club 1.5 times as long as remaining antennomeres together. Apex of aedeagus apically widened (lateral view), with a median hook ventrally .............. ....................................................................................................................... M. dubia (Arrow, 1916)

5 Basis of clypeus dull ......................................................................................................................... 6

– Basis of clypeus shiny ...................................................................................................................... 9

6. Metatibia wide (ratio width/length: 1/2.4–2.6). Metacoxal apophysis with very dense, evenly short, scale-like setae .................................................................................................................................. 7

– Metatibia slender (ratio width/length: 1/3.0). Metacoxal apophysis without scale-like setae.Aedeagus with a single narrowly extended tube ............................. M. schintlmeisteri Fabrizi & Ahrens, 2014

7. Body size smaller 10 mm (ca 8.8 mm) ......................................... M. woodi Fabrizi & Ahrens, 2014

– Body size larger 10 mm (ca 11.8 mm) .............................................................................................. 8

8. Aedeagus apically deeply bifurcate ..................................... M. kuruwitana Fabrizi & Ahrens, 2014

– Aedeagus apically not incised .................................................................... M. coxalis (Moser, 1915)

9. Distal operculum of aedeagus enlarged apically ............................................................................ 10

– Apex of aedeagus almost evenly narrowed, distal operculum of aedeagus not significantly enlarged apically .............................................................................................................................................11

10. Aedeagus ventrally with a large convex elevation at middle. Distal operculum of aedeagus moderately large, not half as wide as width of aedeagus ......................................... M. fistulosa (Brenske, 1898)

– Aedeagus ventrally without a large convex elevation at middle. Distal operculum of aedeagus large, as wide as width of aedeagus .................................................. M. poyagana Fabrizi & Ahrens, 2014

11. Aedeagus ventrally with a large convex elevation at middle ............................................................. ................................................................................................ M. badullana Fabrizi & Ahrens, 2014

– Aedeagus ventrally without a large convex elevation at middle .................................................... 12

12. Aedeagus strongly compressed at middle, its distal part strongly narrowed towards apex (lateral view) and distinctly narrowed a quarter before apex (dorsal view) ................................................... ......................................................................................................... M. weligamana (Brenske, 1900)

– Aedeagus moderately compressed at middle, its distal part less narrowed towards apex (lateral view) and less narrowed a quarter before apex (dorsal view) ................................... M. deenstana sp. nov.

13. Elytra with a longitudinal row of widely separated impunctate spots each bearing at centre a coarse puncture with an erect seta ............................................................................................................. 14

– Elytra without widely separated impunctate spots bearing at centre a coarse puncture with an erect seta .................................................................................................................................................. 17

14. Body shape more elongate. Distal part of aedeagus short and wide (lateral view) ........................ 15

– Body shape oval. Distal part of aedeagus longer and narrower (lateral view) ................................... .......................................................................................................................... M. hiyarensis sp. nov.

15. Aedeagus with a ventral hook ......................................................................................................... 16

– Aedeagus without a ventral hook .............................................................. M. karunaratnae sp. nov.

16. Pronotum with double pilosity composed of short adjacent and long erect setae. Aedeagus, with a sharp ventral hook before the middle ................................... M. anderssoni Fabrizi & Ahrens, 2014

– Pronotum with simple pilosity composed of short adjacent setae. Aedeagus, with a sharp ventral hook before the apex ................................................................. M. romanoi Fabrizi & Ahrens, 2014

17. Pronotum and elytra with fine and significantly larger punctures .................................................. 18

– Pronotum and elytra only with fine, dense punctures. Elytra unicoloured ..................................... 22

18. Aedeagus simple, without lobes or branches. Elytral intervals with dark stripes .............................. ........................................................................................... M. galdaththana Ranasinghe et al., 2020

– Aedeagus with apical or lateral lobes or branches .......................................................................... 19

19. Apical margin of metacoxa without setae ....................................................................................... 20

– Apical margin of metacoxa with dense short setae ......................................................................... 21

20 Median apophysis of metacoxa with dense, evenly short setae. Ventral metatibial spur slightly longer than the basal metatarsomere ...................................................... M. brincki Fabrizi & Ahrens, 2014

– Median apophysis of metacoxa with moderately dense, unevenly long setae. Ventral metatibial spur almost as long as the two basal metatarsomeres combined .......... M. heveli Fabrizi & Ahrens, 2014

21. Ventral metatibial spur almost straight and not elongated. Median apophysis of metacoxa with moderately dense and unevenly short setae ................. M. uggalkaltotensis Fabrizi & Ahrens, 2014

– Ventral metatibial spur strongly curved and almost as long as the three basal metatarsomeres combined. Median apophysis of metacoxa with very dense and evenly short setae .......................... .............................................................................................. M. diyalumana Fabrizi & Ahrens, 2014

22. Apical margin of metacoxa with dense, short setae ........................................................................ 23

– Apical margin of metacoxa without setae ....................................................................................... 24

23. Colour reddish brown, body smaller than 7.5 mm .............. M. tricuspidata Fabrizi & Ahrens, 2014

– Colour dark reddish brown, body larger than 8.0 mm ........ M. nilaveliensis Fabrizi & Ahrens, 2014

24. Body smaller than 7 mm ................................................................................................................. 25

– Body larger than 7 mm ................................................................................................................... 28

25. Antennal club as long as remaining antennomeres combined ........................................................ 26

– Antennal club slightly longer than the remaining antennomeres combined ....................................... .................................................................................................. M. bisornata Fabrizi & Ahrens, 2014

26. Dorsal distal lobe of aedeagus simple ............................................................................................ 27

– Dorsal distal lobe of aedeagus with a long lobiform extension at the base ............ M. windy sp. nov.

27. Ventral distal lobe of aedeagus (i.e., including the fused parameres) extremely extended medially exceeding almost the maximum width of phallobase (dorsal view) ..... M. pubescens (Arrow, 1916)

– Ventral distal lobe of aedeagus (i.e., including the fused parameres) not extended mesally but constant in width over its entire length and being much narrower than the phallobase (dorsal view) ....................................................................................................................... M. dambullana sp. nov.

28. Aedeagus with at least two apical processes .................................................................................. 29

– Aedeagus with a single principal apical process ..................... M. yalaensis Fabrizi & Ahrens, 2014

29. Aedeagus with at two apical processes. 3 rd abdominal sternite without median tubercle .............. 31

– Aedeagus with at three apical processes ......................................................................................... 30

30. 3 rd abdominal sternite with a median tubercle. Right distal lobe of aedeagus split before apex .... 34

– 3 rd abdominal sternite without a median tubercle. Right distal lobe of aedeagus not split before apex ........................................................................................................................... M. kishi sp. nov.

31. Median apophysis of metacoxa with dense, evenly short setae ...................................................... 32

– Median apophysis of metacoxa with moderately dense, unevenly long setae ................................... ............................................................................................ M. mavilluensis Fabrizi & Ahrens, 2014

32. Aedeagus in lateral view strongly enlarged ventrally, with a marsupium-like excavation ................ ......................................................................................................... M. flinti Fabrizi & Ahrens, 2014

– Aedeagus in lateral not enlarged ventrally ..................................................................................... 33

33. Right lateral process of aedeagus convex at the tip .............. M. kandyensis Fabrizi & Ahrens, 2014

– Right lateral process of aedeagus acute at the tip ....................... M. hastata Fabrizi & Ahrens, 2014

34. Setae on disc of pronotum almost missing. Right distal lobe of aedeagus shorter, shorter than the rest of the basal part of the phallobase, strongly narrowed towards apex ................................................. ............................................................................................... M. cervicornis Ranasinghe et al., 2020

– Setae on disc of pronotum dense. Right distal lobe of aedeagus extremely long, as long as the rest of the basal part of the phallobase, equal in width over its entire length ................... M. haniel sp. nov.