Key to the Rhagovelia from Costa Rica [modified from Bacon (1956) and Polhemus (1997)]

1 Pronotum of apterous forms at midline shorter than dorsal length of an eye (Fig. 15)............ ( angustipes complex)... 2

- Pronotum of apterous forms at midline longer than dorsal length of an eye (Fig. 16)................................ 9

2 Hind femur unarmed in both males and females.................................... Rhagovelia danpolhemi sp. nov.

- Hind femur with spines at least in males................................................................... 3

3 Base of last abdominal sternite of male bearing a stout, slightly curved spine........................ Rhagovelia spinosa

- Base of last abdominal sternite of male without such a spine................................................... 4

4 Hind trochanter of male and female with short spines; hind femur of male strongly incrassate.......... Rhagovelia calopa

- Hind trochanter of male and female without spines; hind femur of male not strongly incrassate....................... 5

5 Antennomere II longer than or subequal to III.............................................................. 6

- Antennomere II shorter than III......................................................................... 7

6 Hind tibia of male and female with short spines along entire length (those of females may be weak, but present), besides apical spur........................................................................... Rhagovelia tenuipes (part)

- Hind tibia of male and female without short spines along its length, at most with apical spur......... Rhagovelia bisignata

7 Hind tibia of male and female with short spines along entire length (those of females may be weak, but present), besides apical spur........................................................................... Rhagovelia tenuipes (part)

- Hind tibia of male and female without short spines along its length, at most with apical spur......................... 8

8 Male hind tibia without apical spur; apterous female with shining black spots on last two abdominal tergites................................................................................................... Rhagovelia tantilla

- Male hind tibia with apical spur; apterous female with shining black spots on last four or five abdominal tergites.............................................................................................. Rhagovelia angustipes

9 Male with posterolateral margins of abdominal segment VII surrounding genital cavity bearing large black denticles (Fig. 17); macropterous female with an elevated posterior projection at apex of pronotum (Fig. 18 A, B)....................... 10

- Male with posterolateral margins of abdominal segment VII surrounding genital cavity without large black denticles; macropterous female without elevated posterior projection at apex of pronotum.................................. 16

10 Female with central section of middle femur with a transverse constriction (Fig. 19)................. ( spinigera group) 11

- Female with central section of middle femur without a transverse constriction........................ ( armata group) 12

11 Male middle femur armed with numerous small black spines on proximal 1/3 of posterior margin; female with long, slender, erect black setae often present on margins of connexiva VI–VII (most easily seen in lateral view)..... Rhagovelia spinigera

- Male middle femur lacking small black spines on proximal 1/3 of posterior margin; female lacking erect, black setae on margins of connexiva VI–VII............................................................... Rhagovelia formosa

12 Male and female with terminal genital segment acuminate, prolonged into a spine-like process (similar to Fig. 20)............................................................................................ Rhagovelia acuminata

- Male and female terminal genital segment not acuminate, sometimes ending in an acute angle, but never prolonged into a spine-like process (similar to Fig. 21).................................................................... 13

13 Female with connexival margins relatively straight, tapering evenly toward apex of abdomen, never suddenly convergent adjacent to or after tergite III (similar to Fig. 22)............................................... Rhagovelia crassipes

- Female with connexival margins sharply convergent adjacent to or after abdominal tergite III (similar to Fig. 23)........ 14

14 Lateral portions of mesosternum lacking small black denticles................................... Rhagovelia armata

- Lateral portions of mesosternum bearing numerous small black denticles....................................... 15

15 Disk of pronotum thickly covered by moderately long, recumbent pale pubescence; venter of abdomen with numerous small black denticles along its entire length....................................................... Rhagovelia scabra

- Disk of pronotum moderately covered by short, recumbent golden setae; venter of abdomen with black denticles on lateral portions of basal segments only............................................................... Rhagovelia solida

16 Male and female hind tibia with crescent-shaped apical spur (Fig. 24)............................. ( elegans group) 17

- Male and female hind tibia with apical spur, when present, straight or slightly curved (Fig. 14)...................... 18

17 Male and female with terminal genital segment acuminate posteriorly, prolonged into an extremely slender spine-like process (Fig. 20)............................................................................. Rhagovelia uncinata

- Male and female terminal genital segment not acuminate posteriorly, often ending in an acute angle, but not prolonged into a spine-like process (Fig. 21)............................................................... Rhagovelia elegans

18 Abdomen of apterous female with dorsal longitudinal median carina (indistinct in some cases) (Fig. 25); abdominal connexiva of apterous female thickened in some species (Fig. 25); male hind tibia only with subequal spines, besides apical spur............................................................................................ (hirtipes group) 19

- Abdomen of apterous female without longitudinal carina; abdominal connexiva of apterous female never thickened; male hind tibia of some species displaying one or more spines larger than the others, besides apical spur (as in Fig. 26)................................................................................................... (robusta group) 20

19 Apterous female connexiva bowed inward and glabrous adjacent to abdominal tergites III–V; male abdominal sternite VIII lacking a median carina.................................................................. Rhagovelia reclusa

- Apterous female connexiva not bowed inward and glabrous adjacent to tergites III–V; male abdominal sternite VIII usually with a low median carina.............................................................. Rhagovelia femoralis

20 Length of apterous forms 3.90–4.10 mm; male hind trochanter bearing 2–4 small subequal spines; male hind tibia with small peg-like spines throughout most of its length and slightly enlarged spines approximately on 1/3 distance to apex............................................................................................ Rhagovelia johnpolhemi

- Length of apterous forms at most 3.50 mm; male hind trochanter bearing 0–1 small spine; male hind tibia with small subequal peg-like spines...................................................................................... 21

21 Male fore trochanter without tuft of long stout setae; male hind femur weakly widened; male parameres with distal portion long, slender and curved (Fig. 27).......................................................... Rhagovelia sehnali

- Male fore trochanter with a tuft of long stout black setae (Fig. 10); male hind femur moderately widened; male parameres with distal portion not elongated and curved (Fig. 13).................................... Rhagovelia springerae sp. nov.