Willowsia, Shoebotham, 1917

Pan, Zhixiang & Zhang, Feng, 2016, Contribution to the Willowsia species having body scales of the long basal rib type: four new species and a redescription of W. qui (Collembola: Entomobryidae), European Journal of Taxonomy 245, pp. 1-25 : 23-24

Key to the Willowsia species having scales of the long rib type

1. Mucro with subapical tooth much smaller than apical one and basal spine long, reaching midway between the subapical and apical teeth ...................................... W. samarkandica Martynova, 1972

– Mucro with teeth subequal and basal spine short, reaching the apex of subapical tooth ................. 2

2. Unguiculus truncate ............................................................................... W. formosana (Denis, 1929) – Unguiculus lanceolate ....................................................................................................................... 3

3. Pigment scattered on all terga ................................................................... W. buskii (Lubbock, 1869) – Pigment not uniformly distributed on each tergum ......................................................................... 4

4. Ant. I–II and ventral side of manubrium scaled ........ W. guangdongensis Zhang, Xu & Chen, 2007 – Antennae and manubrium unscaled ................................................................................................. 5

5. Each labral papilla with at least two denticles ........................................ W. jacobsoni (Börner, 1913) – Labral papillae conical ...................................................................................................................... 6

6. Abd. I with 7+7 mac; Abd. II with 6+6 central mac … W. potapovi Zhang, Chen & Deharveng, 2011 – Abd. I with at most 4+4 mac; Abd. II with at most 5+5 central mac ............................................... 7

7. Abd. II with 5+5 central mac ................................. W. yiningensis Zhang, Chen & Deharveng, 2011 – Abd. II with at most 4+4 central mac ............................................................................................... 8

8. Abd. II with 4+4 central mac ........................................... W. mekila Christiansen & Bellinger, 1992 – Abd. II with 3+3 central mac ............................................................................................................ 9

9. Abd. I with 4+4 mac ........................................................... W. qui Zhang, Chen & Deharveng, 2011 – Abd. I with at most 3+3 mac ............................................................................................................10

10. Abd. III with 2+2 central mac .........................................................................................................11 – Abd. III with 3+3 central mac .........................................................................................................12

11. Cephalic mac S 0 and S 0 ' present; Abd. IV with 5+5 central mac ………… W. pseudobuskii sp. nov. – Cephalic mac S 0 and S 0 ' absent; Abd. IV with 7+7 central mac ………………………………………… …………………………………………………………………… W. pseudoplatani Zhang & Pan sp. nov.

12. Abd. II–III with transverse bands ...................................................................................................13 – Abd. II–III without transverse bands ......................................... W. nigromaculata (Lubbock, 1873)

13. Metathorax pigmented; cephalic S 0 absent; a3 on Th. III as mic ....................................................14 – Metathorax unpigmented; cephalic S 0 present; a3 on Th. III as mac ................................................. …………………………………………………………………………… W. fascia Zhang & Pan sp. nov.

14. Abd. IV unpigmented; Th. II with 1+1 medio-medial and 2+2 medio-lateral mac …………………… …………………………………………………………………………………………… W. similis sp. nov. – Abd. IV pigmented; Th. II with only 1+1 medio-lateral mac .................... W. platani (Nicolet, 1842)