Zalea

McAlpine, D. K., 2007, The Surge Flies (Diptera: Canacidae: Zaleinae) of Australasia and Notes on Tethinid-Canacid Morphology and Relationships, Records of the Australian Museum 59 (1), pp. 27-64 : 46

Key to species of Zalea

1 Scutellum with shorter pair of bristles at apex, in addition to two major pairs; anterior crossvein meeting vein 4 well before mid length of discal cell; posterior fronto-orbital bristle strongly curved outwards, not reclinate, in contrast to other fronto-orbitals; upper postgenal setulae forming an almost vertical series; wing typically over 2.1 mm long; habitat New Zealand.................................................................. ( wisei group) 2

—— Scutellum with two pairs of major bristles only; anterior crossvein meeting vein 4 at or beyond mid-length of discal cell; posterior fronto-orbital bristle reclinate and slightly curved outwards, its orientation not markedly different from mid fronto-orbital; upper postgenal setulae usually absent or little developed (except in Z. earlyi ); habitat Australia or, if New Zealand, then wing under 2.1 mm long ........................................................................ 3

2 Triangle formed from joining centres of ocelli broader than equilateral triangle; antennal segment 5 less than 2.5× as long as wide; palpus not extending anteriorly beyond prelabrum when proboscis is withdrawn; cheek region descending in outline and most prominent posteriorly ( Fig. 70) ...................................................................... Zalea sp. 1

—— Triangle formed by joining centres of ocelli not broader than equilateral triangle; antennal segment 5 more than 3.5× as long as wide; palpus extending distinctly beyond prelabrum when proboscis is withdrawn; cheek region not more ventrally prominent posteriorly than anteriorly ( Fig. 68) ......................................................................................... wisei

3 Prosternum with precoxal bridge on each side ( Fig. 15); male (where known): posterior surstylus extensively microtrichose on outer surface; habitat New Zealand................................................................... ( horningi group) 4

—— Prosternum without precoxal bridge ( Fig. 16); male (unknown in sp. 2): posterior surstylus almost devoid of microtrichia; habitat mostly Australia, but see also sp. 2 (northern New Zealand) ................................. ( minor group) 10

4 Postgenal setulae forming an almost vertical series; postvertical bristles slightly divergent to subparallel; female: tergite 7 with pair of separate broad lateral plates detached from T-shaped apodeme .................................................................................................................................. earlyi

—— Postgenal setulae absent or little developed; postvertical bristles variable; female (where known): tergite 7 and its anterior apodeme forming a single, lobed sclerite ...................................................................................................... 5

5 Postvertical bristles divergent; male: anterior surstylus much longer than posterior surstylus, strongly curved so that apex is directed posteriorly; posterior surstylus broad, with enlarged anterior setulae near mid-length .......................................................................................................... johnsi

—— Postvertical bristles convergent or rarely parallel; male: anterior surstylus variable, but usually not markedly longer than posterior surstylus; posterior surstylus without such large anterior setulae ............................................................................................................................................ 6