Vertex about 0.24x head width in dorsal view; inner vertical seta and reclinate orbital seta missing in the material examined; ocellar seta weak almost not differentiated from ocellar triangle setulae; fronto-orbital plate with about 12 frontal setae, upper seta slightly stronger than fronto-orbital setulae, one or two setae situated below lower margin of pedicel; fronto-orbital plate slightly narrower than parafacial; first flagellomere about 1.3x length of pedicel; pedicel about 2.8x length of scape; third aristomere about 1.9x length of first flagellomere; facial ridge with row of stout supravibrissal setae on lower 0.4 of its length, setae 0.2-0.46x length of vibrissa; anteroventral margin of gena with a row of setae extending backward, setae 0.26-0.4x length of vibrissa.
Vertex about 0.3x head width in dorsal view; inner vertical seta stout and curved backward, about 1.5x length of reclinate orbital seta; ocellar seta weak almost not differentiated from ocellar triangle setulae; fronto-orbital plate with about 13 frontal setae, upper seta slightly stronger than fronto-orbital setulae; frontal setae ending just before lower margin of pedicel; fronto-orbital plate slightly narrower than parafacial; first flagellomere about 1.3x length of pedicel; pedicel about 2.95x length of scape; third aristomere about 1.8x length of first flagellomere; facial ridge with row of stout supravibrissal setae on lower 0.4 of its length, setae 0.3-0.5x length of vibrissa; anteroventral margin of gena with row of setae extending backward, setae 0.3-0.4x length of vibrissa.
Fronto-orbital bristles reclinate, rather short (posterior fronto-orbital bristle ca 0.6x length of inner vertical seta), of similar length and fairly widely spaced (distance between bristles equal to distance between posterior dorsocentral bristle and inner vertical seta); setula between the fronto-orbital bristles.
Fronto-orbital bristles reclinate, fairly short, anterior fronto-orbital bristle slightly shorter than posterior fronto-orbital bristle, the latter bristle ca 0.5 x length of inner vertical seta.
Head: Eye microsetulose (sometimes sparsely so); occiput with a silvery-white, microtomentose area immediately adjacent to posterior margin of compound eye; frons with 1 fronto-orbital seta, reclinate; postvertical setae present, divergent; ocellar setae present, well developed; face uniformly sclerotized and transversely arched (shield-like in Scutops Coquilett, 1904); face setose laterally, strongly receded ventrally, extended laterally below gena; gena extended anterodorsally, bearing a row of setae, with anterior one inserted well above oral margin; mouth opening large.
These five genera comprise a well-established, monophyletic assemblage, with corroborative synapomorphies as follows: (1) mouth opening large; (2) occiput with a silvery-white, microtomentose area immediately adjacent to the posterior margin of the compound eye; (3) only one fronto-orbital seta, reclinate; (4) costal vein short, extended only to vein [R.sub.4 + 5]; (5) vein Cu[A.sub.2] reduced or absent; (6) several characters of the male terminalia (see Griffiths 1972).
To briefly summarise, features of the African Pacycerina that are immediately striking include: (1) tiny ocellar setulae ('ausserordentlich klein' [extraordinarily small] in Becker's (1895: 250) words), (2) incurved anterior fronto-orbital bristles (
reclinate in most Afrotropical lauxaniids, except Chaetolauxania Kertesz), (3) bulging prefrons and lateral black spots (other Afrotropical lauxaniid genera lack such a tumid prefrons and maculation), (4) elongated postpedicel, (5) two acrostrichal bristle rows on mesoscutum, (6) no profemoral ctenidium, (7) usually dark brown protibia and protarsi (relative to yellow meso- and metatibiae and tarsi), (8) the presence of paired black spots on T6 in some species, and (9) the absence of an aedeagus in the male of all species.
Chaetotaxy: 3 orb, anterior inclinate and as long as distance between orbits at this level, middle and posterior orb reclinate; pvt distinct and crossed, little more than half length of divergent ocellars; 1 vti and 1 vte, strong.
Chaetotaxy: 3 strong orb, the anterior strongly inclinate, middle and posterior orb reclinate;pvt minute, barely visible; 1 vti and 1 vte both strong; oc short and strongly lateroclinate; numerous fine short setulae over most of fr, including on intervening spaces between orb setae.
Diagnosis: Yellow species with very large hypopygium with complex structures easily visible externally; spinose elongate cerc; anterior orb
reclinate, posterior 2 orb lateroclinate; 1 strong posterior dc with shorter seta anterior to it.
Chaetotaxy: 3
reclinate orb with short setula in front, 2 long ocellars widely spaced almost parallel, 10 fr setulae and a pair of long setae in front of oc triangle; 1 vti and 1 vte, pvt convergent.