Key to adult males with elongated hypopygial anal points of the subgenus Cladotanytarsus s. str.

1. Stem of median volsella bearing furcate/branched lamellae (Figs 1 E, 3E, 4E, 5B, D)......... Cladotanytarsus Kieffer ... 2

-. Median volsella never as above................................................... other Tanytarsini ...not keyed

2. Apices of middle and hind leg tibiae without stout lobes armed with dense setae but with fan-shaped combs, at least one comb bearing spur (Kikuchi & Sasa 1990, fig. 20d, e; Giłka 2001, fig. 1f; Jacobsen & Bilyj 2007, fig. 4; Giłka 2009a, figs 11, 12). Inferior volsella never with globular swelling ventrally, with knee-shaped extension at most (Figs 1 B, F, 3A, B, F, 4A, B, F, 5B, D; Giłka & Dobosz 2015, fig. 1d).....................................subgenus Cladotanytarsus s. str. Kieffer .... 3

-. Apices of middle and hind leg tibiae bearing stout lobes armed with dense setae, combs and spurs vestigial if present (Giłka 2011b, figs 2c, d, 4b–e, 5, 8, 11, 12: b, c). Inferior volsella bearing distinct globular swelling ventrally (Giłka 2011b, figs 2h, 4k, 5g, 8g, 11g, 12h)................................................... subgenus Lenziella Kieffer ... not keyed

3. Anal point with longitudinal bar (Reiss 1991, fig. 2)...................................... .. C. ecristatus (Morocco)

-. Anal point without longitudinal bar...................................................................... 4

4. Stem of median volsella shorter than its lamellae or stem and lamellae of similar length (Figs 4 B, E, 5B; Glover 1973, fig. 2 4b; Langton & Garcia 2000, fig. 1a; Giłka 2001, fig. 1e; Giłka 2009a, fig. 16; Giłka & Dobosz 2015, fig. 1c)................5

-. Stem of median volsella distinctly longer than its lamellae (Figs 1 B, E, 3B, E, 5D; Jacobsen & Bilyj 2007, fig. 5)....... 13

5. Anal point in shape of elongated arrow, evenly tapering to pointed apex (Glover 1973, fig. 24a; Kikuchi & Sasa 1990, fig. 21c; Sasa & Suzuki 2000, fig. 3i –k; Giłka 2009a, fig. 13), exceptionally truncate (Glover 1973, fig. 24d)................... 6

-. Anal point with parallel-sided distal elongation and/or apically blunt/rounded (Figs 4 A, C, 5A; Langton & Garcia 2000, figs 1a, 2a, b; Langton & McBean 2010, figs 1–3; Giłka & Dobosz 2015, fig. 1a, b; NMNS 200:070) otherwise broad at base (Giłka 2001, fig. 1b, c)...................................................................................... 9

6. Spinulae absent.......................................................................................7

-. Spinulae present..................................................................................... 8

7. Anal point darkly pigmented, black or dark brown; gonostyli slender (Giłka 2009a, fig. 13)................................................................................................. .. C. sagittifer (United Arab Emirates)

-. Anal point ordinarily coloured; gonostyli stout (Glover 1973, fig. 24)......................... C. bilinearis (Australia)

8. Inferior volsella cuneiform, evenly tapering to narrow apex (Kikuchi & Sasa 1990, fig. 21f & NMNS 199:018)........................................................................................ C. tobaquindecimus (Sumatra)

-. Inferior volsella parallel-sided, with broadly rounded apex (Sasa & Suzuki 2000, fig. 3p, q & NMNS 385:002)............................................................................................... C. isigacedeus (Japan)

9. Inferior volsella with distinct lateral knee-shaped extension at base (Giłka & Dobosz 2015, fig. 1a, d)................................................................................................. C. stylifer (New Caledonia)

-. Inferior volsella without distinct lateral knee-shaped extension at base (Figs 4 A, B, F, 5A, B; Langton & Garcia 2000, fig. 1a; Giłka 2001, fig. 1b; Langton & McBean 2010, fig. 1)....................................................... 10

10. Inferior volsella slender at base (Fig. 5 A, B; Langton & Garcia 2000, fig. 1a; Giłka 2001, fig. 1b). Stem of median volsella slender, bearing 3–4 branched lamellae, stem and its lamellae of similar length (Fig. 5 B; Langton & Garcia 2000, fig. 1a; Giłka 2001, fig. 1e)....................................................................................... 11

-. Inferior volsella strongly broadened at base (Fig. 4 B, F; Langton & McBean 2010, fig. 1). Stem of median volsella stocky, bearing 6–7 branched lamellae, the longest lamella longer than its stem (Fig. 4 B, E; Langton & McBean 2010, figs 1, 4). 12

11. Anal point narrow at base, rounded apically or club-shaped (Fig. 5 A; Langton & Garcia 2000, figs 1a, 2a, b; NMNS 200:070).................................................................................. C. conversus (Eurasia)

-. Anal point broad at base, distal elongation pointed (Giłka 2001, fig. 1b, c)......................... C. cyrylae (Europe)

12. Spinulae absent, tip of digitus hooked (Langton & McBean 2010, figs 1–3)................ C. donmcbeani (Great Britain)

-. Spinulae usually present, digitus straight (Fig. 4 A, C, D)................................. Cladotanytarsus sp. (USA)

13. Crests of anal point very thin or not developed (Fig. 1 A, C; Jacobsen & Bilyj 2007, figs 5–7). Acrostichal setae usually absent.................................................................................. C. acornutus (Nearctic)

-. Crests of anal point well-developed (Figs 3 A, C, 5C; Bilyj & Davies, fig. 7). Acrostichal setae always present...........14

14. Median volsella with 2–3 weak branched lamellae; inferior volsella without distinct lateral knee-shaped extension at base or angular dorsomedian ridge (Bilyj & Davies, fig. 7). Small species, wing length ca. 1.2–1.4 mm ..... C. muricatus (Canada)

-. Median volsella with 6–7 strong branched lamellae (Figs 3 B, E, 5D); inferior volsella with distinct lateral knee-shaped extension at base and well-developed angular dorsomedian ridge (Figs 3 A, B, F, 5D). Species moderate in size, wing length ca. 1.5– 2.5 mm .............................................................................................15

15. Superior volsella slender, slightly swollen distally, covered with sparse microtrichia on basal part dorsally (Fig. 3 A, D). Lamellae of median volsella slightly curved, arranged evenly on median and apical part of stem (Fig. 3 B, E)... C. bilyji (Nearctic)

-. Superior volsella broad at base, tapering towards tip, covered with dense microtrichia on proximal 2/3 part (Fig. 5 C; Giłka 2001, fig. 7b, d). Lamellae of median volsella strongly curved, densely placed on apical part of stem (Fig. 5 D; Giłka 2001, fig. 7e)........................................................................... C. nigrovittatus (Holarctic)