Updated key to the species of Messapus

1. Males (males of M. meridionalis Haddad & Mbo, 2015 and M. seiugatus Haddad & Mbo, 2015 unknown).............. 2

- Females............................................................................................. 7

2. Palp with single elongate slender RTA; embolus very long, originating prolaterally, curving in broad arc distally and ending midway along the retrolateral margin of the tegulum (Haddad & Mbo 2015: figs 37, 38, 43, 44).................................................................................................. M. megae Haddad & Mbo, 2015

- Palpal tibia with more than one apophysis; embolus shorter.................................................... 3

3. Palpal tibia bearing four retrolateral apophyses, dorsal RTA bifid; embolus short, needle-shaped, obliquely situated beneath sclerotised tegular apophysis (Haddad 2005: figs 4–6); large spiders,> 11.7 mm in length........ M. natalis (Pocock, 1898)

- Palpal tibia bearing two or three retrolateral apophyses, dorsal RTA not bifid; embolus not hidden beneath tegular apophysis, slightly curved and flattened; medium to large spiders, <10 mm in length......................................... 4

4. Palpal tibia with two apophyses; dorsal RTA massive, sickle-shaped in retrolateral view, as long as dorsal surface of tibia and approximately half the length of the cymbium (Figs 17, 39).................................................... 5

- Palpal tibia with three apophyses; dorsal RTA shorter, triangular (Haddad & Mbo 2015: fig. 54) or hatchet-shaped (Haddad 2013: fig. 38), clearly shorter than dorsal surface of tibia and less than half the length of the cymbium.................. 6

5. Tegulum with distinct spike-like prodistal tegular apophysis; embolus originating mediodistally, axis directed approximately towards 1 o’clock (Figs 32, 37).................................................. M. tigris Haddad & Mbo, 2015

- Tegulum without prodistal tegular apophysis; embolus originating prodistally, broad and flattened, slightly curved and transversely oriented (Figs 16, 24)...................................................... M. mygaloides sp. nov.

6. Dorsal RTA triangular, originating dorsally above two smaller teeth-like ventral apophyses (Haddad & Mbo 2015: figs 39, 40, 53, 54).................................................................... M. tropicus Haddad & Mbo, 2015

- Dorsal RTA stout, hatchet-shaped, slightly curved ventrally in retrolateral view, originating dorsally above tongue-like ventral RTA, with small lobed apophysis between them proximally (Haddad 2013: figs 36, 37)............ M. martini Simon, 1898

7. Epigyne with horseshoe-shaped ridges; cheliceral promarginal pronounced mound absent............................ 8

- Epigyne with oval- or slit-shaped ridges; cheliceral promarginal pronounced mound present.......................... 9

8. Lateral margins of epigynal ridges almost parallel but converging slightly posteriorly, forming subrectangular atrium (Haddad & Mbo 2015: figs 33, 45); copulatory ducts longitudinal to epigynal axis; ST II without anterior pore-bearing receptacle (Haddad & Mbo 2015: fig. 46)............................................. M. meridionalis Haddad & Mbo, 2015

- Lateral margins of epigynal ridges broadening medially, forming diamond-shaped atrium (Haddad 2013: fig. 34); copulatory openings obliquely oriented to epigyne axis; ST II with anterior pore-bearing receptacle (Haddad 2013: fig. 35)............................................................................................ M. martini Simon, 1898

9. Epigyne ventrally with strongly sclerotized ridges forming complete ovals, directed anterolaterally along their axis....... 10

- Epigyne ventrally with ridges forming incomplete ovals or with curved ridges.................................... 11

10. Epigynal ridges touching medially (Haddad 2005: figs 1, 2); spermathecae linked by broad median U-shaped tube (Haddad 2005: fig. 3); large spiders,> 15 mm in length........................................... M. natalis (Pocock, 1898)

- Epigynal ridges clearly separated (Haddad & Mbo 2015: fig. 41); spermathecae not connected by broad median U-shaped tube, but projecting anterolaterally (Haddad & Mbo 2015: fig. 42); small spiders, ca. 7 mm in length.................................................................................................. M. megae Haddad & Mbo, 2015

11. Epigyne with two widely separated oblique incomplete oval ridges, with their anterior margins directed anteromesally; ST II large, suboval, situated laterally (Figs 12, 13; Haddad & Mbo 2015: figs 35, 49, 50)............................... 12

- Epigyne with curved epigynal ridges, oriented more or less parallel to body axis; ST II either small, round and medially situated (Haddad & Mbo 2015: fig. 48) or with large lateral extensions projecting posteriorly (Haddad & Mbo 2015: fig. 52)...... 13

12. Epigynal ridges with distinct oval lateral lobe positioned posterior to lateral ridge (Figs 10, 12)..... M. mygaloides sp. nov.

- Epigynal ridges with narrow fringe along their anterior margin, without oval lateral lobe (Fig. 46; Haddad & Mbo 2015: fig. 49)......................................................................... M. tigris Haddad & Mbo, 2015

13. Epigyne with small ridges, curved inwards, copulatory openings anteriorly in ridges (Haddad & Mbo 2015: figs 34, 47)............................................................................. M. seiugatus Haddad & Mbo, 2015

- Epigyne with large ridges, curved outwards, forming ovoid median atrium, with copulatory openings posteriorly in ridges (Haddad & Mbo 2015: figs 36, 51)............................................. M. tropicus Haddad & Mbo, 2015