Key to Epanerchodus species known from mainland China, based on males:

1 Head considerably broader than collum.................................................................... 2

- In width, head subequal to or narrower than collum.......................................................... 6

2 Most of sterna with two small cones (male) or knobs (female) near each coxa. Caudolateral corner of all postcollum paraterga strongly spiniform and extending behind rear tergal margin. Caves in Yunnan................................ E. soror

- Sterna devoid of distinct cones or knobs. Caudolateral corner of paraterga of anterior body third at most slightly acutangular (up to 70º), neither spiniform nor considerably drawn behind rear tergal margin.................................... 3

3 Gonopods highly variable even between syntopic males, mostly much like in Fig. 6, a small exomere often present, but some- times totally suppressed, 2–3 processes or evident, elaborate outgrowths at base of an elongated endomere. Guangxi. At least two males are thus necessary to secure a correct identification........................................ E. orientalis

- Gonopods far more stable, truly species-characteristic; endomere stout........................................... 4

4 Body ca 15–16 mm long, brown. Sphaerotrichomes present on male postfemora, tibiae and tarsi. Gonopod with a small denti- form exomere.......................................................................... E. sphaerisetosus

- Body considerably smaller, at most ca 12 mm long. Sphaerotrichomes absent. Exomere either absent or a prominent ancori- form structure........................................................................................ 5

5 Adult body ca 8–12 mm long, 1.1–1.5 mm wide. Gonopod endomere ancoriform, an exomere totally absent (Fig. 19). Sichuan.................................................................................. E. schawalleri sp. nov.

- Body ca 6 mm long, 0.7 mm wide. Gonopod deeply bifid, exomere prominent and ancoriform. Mt Tianmu, Zhejiang................................................................................................ E. eurycornutus

6 Collum and head subequal in width....................................................................... 7

- Collum considerably broader than head.................................................................... 8

7 Paraterga clearly upturmed, mostly elevated above dorsum. Antennae very long and slender, reaching behind segment 4 when stretched dorsally. Sphaerotrichomes absent. Yunnan................................................... E. draco

- Paraterga at most only faintly upturmed, mostly only reaching level of dorsum even in male (Figs 7 & 8). Antennae shorter, slightly clavate (Fig. 7), at most reaching behind segment 3 (male) when stretched dorsally. Sphaerotrichomes present on male femora, postfemora, tibiae and tarsi (Fig. 10). Shaanxi.......................................... E. jaegeri sp. nov.

8 Exomere spiniform, at least half as long as a slender endomere, the latter with a rounded subterminal lobule. Caves in Hubei and Sichuan.................................................................................... E. varius

- Exomere either totally wanting or relatively small, endomere devoid of a round subterminal lobule..................... 9

9 Body larger, width of adults> 3.0 mm. Two long processes at base of endomere.................................. 10

- Body smaller, width of adults ≤ 2.5 mm. One or two processes at base of endomere................................ 13

10 Male prefemora slender, not bulging laterally (Figs 14 & 23).................................................. 11

- Male prefemora stouter, at least slightly bulging laterally (Figs 5 & 10).......................................... 12

11 Sphaerotrichomes present (Fig. 23). Exomere absent (Fig. 24). Yunnan......................... E. yunnanensis sp. nov.

- Sphaerotrichomes absent (Fig. 14). Exomere present (Fig. 15). Shaanxi............................ E. martensi sp. nov.

12 All male telopoditomeres with sphaerotrichomes. Exomere clearly bifid. Jilin............................. E. koreanus

- Only male postfemora, tibae and tarsi with sphaerotrichomes (Fig. 5). Exomere (ex) a uniramous spine (Fig. 6). Gansu and Sichuan.................................................................................... E. potanini

13 Body smaller, width ca 1.0 mm. Midbody paraterga relatively narrow, barely broader than prozona. A cave in Yunnan..................................................................................................... E. frater

- Body larger, width ca 2.2 mm. Midbody paraterga considerably broader than prozona. Caves in Guizhou..... E. stylotarseus