Pactola

Key to the species of Pactola

Note: Pactola nigra is not included in this key. Hudson (1950) described it as a colour variety of P. variabilis, but Kuschel (1982) raised it to the status of a distinct species, though without any explanation or diagnosis, writing only “A good species; not a variety of variabilis ”. Hudson’s specimens of P. nigra are deposited in the Museum of New Zealand in Wellington, and colour photographs of the dorsal and lateral habitus of a specimen (erroneously identified as a lectotype for none has been designated) are available on the website of this institution (http:// collections.tepapa.govt.nz/ObjectDetails.aspx?oid=128357). Also photographed are the five labels attached to the specimen, all in the distinctive handwriting of Kuschel, one of which identifies the specimen incorrectly as the holotype, for when Hudson described this in 1950, no single specimen was designated by him as the holotype, the three specimens mentioned by Hudson being syntypes. The main difference between P. variabilis and P. nigra concerns the colour of the dorsal part of the body, in the latter being completely black with two small reddish spots on the elytral disc. However, as its name indicates, P. variabilis is very variable in coloration, and several specimens examined among more than one hundred of this species are very similar in colour to the specimen of P. nigra, as illustrated. It therefore appears that P. n i gr a represents only a colour form of P. variabilis, as assumed originally by Hudson. Study of the type series and male terminalia is needed to confirm this status, but for the moment nigra is here treated as conspecific with P. variabilis and not as a distinct species.

1. Elytra with distinctive, large tubercles (figs. 6, 7)............................................................ 2

- Elytra smooth, without or only with very small tubercles..................................................... 6

2. Elytra with a pair of prominent tubercles only on apical half; tarsal claw with a distinctive, obtusely rounded, basal tooth....................................................................................... P. hudsoni Marshall

- Elytra with tubercles on entire surface; tarsal claw with sharp tooth or simple, with at most basal swelling.............. 3

3. Front and middle femora with distinctive tooth............................................................. 4

- Front and middle femora without tooth..................................................................... 5

4. Front tibiae slender, ca. 6.5 × longer than wide, slightly narrowed apically (fig. 17a); apex of interstriae 5 extended into prominent tubercle exceeding posterolateral elytral margin in dorsal view; interstriae glabrous or only with minute punctures (fig. 6)................................................................................ P. setacea (Montrouzier)

- Front tibiae stout, ca. 5.5 × longer than wide, strongly narrowed apically (fig. 18a); apex of interstriae 5 extended into small, obtuse tooth barely exceeding elytral margin in dorsal view; interstriae with distinctive, small tubercles (fig. 7).................................................................................................. P. proxima sp. n.

5. Elytral disc with maximum width in middle; width of pronotum at base equal to its length; lateral margin of elytra rounded; front tibiae elongate (more than 6 × longer than maximum width); apex of aedeagus nearly straight, incised medially.......................................................................................... P. fuscicornis Broun

- Elytral disc with maximum width beyond middle; width of pronotum at base less than its length; lateral margin of elytra straight; front tibiae stout (less than 5.5 × longer than maximum width), sinuate; apex of aedeagus broadly rounded.............................................................................................. P. variabilis Pascoe

6. Middle femora with distinct tooth........................................................................ 7

- Middle femora without tooth............................................................................. 8

7. Rostrum with median carina (fig. 14d); antennal funicle segments 3–7 longer than wide, club as long as last three funicle segments together (fig. 15d); tooth on front and middle femora acute, strongly protruding (figs. 20a, b); elytra slightly narrowed from middle to apex, interstriae with distinct, polished, suboval tubercles, each bearing a scale (fig. 9)...... P. ma g n a sp. n.

- Rostrum without median carina (fig. 14c); antennal funicle segments 3–7 wider than long, club longer than last six funicle segments together (fig. 15c); tooth on front and middle femora minute (figs. 19a, b); elytra strongly narrowed from middle to apex, interstriae only with microsculpture (fig. 8)....................................... P. convexa (Montrouzier)

8. Tarsal claws without distinct basal appendage..................................................... P. fiji Mazur

- Tarsal claws with distinct, rounded, basal appendage......................................................... 9

9. Hind femora slender, more than 3 × longer than wide (width measured from apex of tooth to upper margin of femur in lateral view)................................................................................. P. demissa Pascoe

- Hind femora stout, less than 2,5 × longer than broad......................................................... 10

10. Elytral disc strongly rounded, ca. 1.2 × longer than maximum width; antennae slender, segment 1 of funicle more than 3 × longer than maximum width; club more than 3.5 × longer than wide............................... P. fairburni Marshall

- Elytral disc elongate, outer margins parallel or weakly curved medially, more than 1.5 × longer than maximum width; antennae stout, segment 1 of funicle 2 × longer than maximum width; club 1.8–2.0 × longer than wide........................ 11

11. Pronotum and elytral disc covered with scales, matte; apex of elytral interstriae 5 extended into obtuse tubercle exceeding posterolateral margin of elytra............................................................ P. posticalis Marshall

- Pronotum and elytral disc asetose, glabrous; apex of elytral interstriae 5 not extended................... P. nitidula Broun