SUBFAMILY EUTELIINAE
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Paectes cristatrix Guenée  
   
Ingura cristatrix
Guenée, 1852, Hist. nat. Insectes, Spec. gen. Lepid. 6: 313.
   
Paectes cristatrix Guenée; Holloway, 1976: 17(part).


Paectes cristatrix
 


Diagnosis.
This and the next species have strikingly marked forewings with a pinkish tinge over the paler bands. P. psaliphora has the dark areas at the dorsum more greenish and the posterior margin of the basal pale mark is convex, directed at the thorax, rather than concave, directed at the dorsum as in cristatrix. The male genitalia of the two species differ mainly in the aedeagus vesica and its ornamentaion: in cristatrix there is a small subbasal lobe, a slender central cornutus, and the vesica tapers slightly to a larger, blade-like distal cornutus at the base of the ductus ejaculatorius; in psaliphora the vesica is more globose with, in Bornean specimens, three cornuti as illustrated (in typical New Guinea psaliphora the vesica has only two cornuti). P. cristatrix can also be defined by the female genitalia where there is a distinctive double angle to the distal limit of the zone of scobination in the basal half of the bursa; in psaliphora this part of the bursa is more globular, much less sclerotised or scobinate.

Taxonomic notes. Both cristatrix and psaliphora belong to a complex of species that ranges through the Indo-Australian tropics to as far east as Samoa. The geography of these species is interesting (Fig. 7) so they are discussed here in some detail. Other members of the complex are:


Figure 7. Distribution of species of the cristatrix group of Paectes. 1. P. poliotis, 2. P. cristatrix, 3. P. psaliphora, 4. P. cyanodes, 5. P. languida, 6. P. fijiensis.

P. cyanodes Turner. This species ranges typically from Queensland to New Guinea and the Solomons. The male resembles that of cristatrix though is slightly less pink; the female has the pale areas more heavily suffused with mauvish pink rendering the wing uniform in tone except for the posterior edge of the basal patch. Apart from this sexual dimorphism the species is defined by two cornuti in the aedeagus - a long basal one and a short distal one, typically broad but varying in other races, at the base of the ductus ejaculatorius. In the female there is a distinctive tongue-like process from the basal part of the bursa copulatrix. A series of races ranges from the Philippines to Samoa.

In the Philippines, Sulawesi and Saleyer there occurs a form that is similar in facies but with the distal cornutus slender and half the length of the more basal one rather than less than a quarter, and with the basal part of the bursa less scobinate. In the Kei Is. is a form with an extra cornutus
near the subbasal one. In New Caledonia and Vanuatu there is a race lacking sexual dimorphism, both sexes being as in typical males (illustrated by Holloway (1979), but referred erroneously to cristatrix). In the Sta Cruz Is. there is a race larger than that in Vanuatu, darker, and with a degree of sexual dimorphism, and in Samoa flies ssp. canescens Tams stat. n., a large race with rather uniform facies in both sexes but a degree of sexual dimorphism also. The eastern end of the distribution of cyanodes is of interest as it is yet another example of the pattern running from the Solomons, New Caledonia and Vanuatu to Samoa that excludes Fiji (Robinson 1975; Holloway 1979, 1983b).

P. languida Warren. This species is known from only two specimens from the Solomons. The male forewing is shades of fawn with a very broad, oblique, paler medial bar extending up to the postmedial loop. The female is smaller, darker, a mauvish grey. In the aedeagus vesica the cornutus at the base of the ductus ejaculatorius is vestigial but there is one long slender one centrally and one slightly smaller one nearer the vestigial one. The female has an angled sclerotised right-hand edge to the basal part of the bursa.

P. fijiensis Robinson stat. n. This species flies in Fiji and Tonga. It resembles cristatrix, though somewhat larger, and was originally described as a subspecies thereof (Robinson 1975). It is here given specific status because of its isolation from cristatrix and relationship to other species in the south-west Pacific. The male aedeagus vesica has a short cornutus at the ductus ejaculatorius as in cyanodes but opposite this there is a single slender cornutus on one side and two long slender ones on the other. The basal part of the bursa copulatrix is slightly asymmetrical and ringed by a diffuse band of scobination at two thirds.

The species of the complex overlap each other considerably, suggestive of extensive dispersal during the evolution of the group. Using the guidelines of allopatric divergence and parsimonious dispersal suggested by Holloway (1982a), the evolution of the group may have proceeded as follows: (1) isolation of cristatrix and poliotis ancestors in mainland Asia and Sundaland respectively; (2) spread of the cristatrix ancestor to as far east as Fiji; (3) isolation and divergence of cristatrix, psaliphora, cyanodes, languida and fijiensis in mainland Asia, Sundaland, somewhere between Sulawesi and New Guinea, the Solomons and Fiji respectively, in allopatric but possibly contiguous ranges; (4) a second dispersal phase leading to the modern ranges of the five species; (5) minor divergence again, especially of cyanodes. If this narrative of events is correct then, as with Aplotelia, dispersal has been almost entirely from west to east, and more particularly involving the species associated with larger land areas initially. Even if Melanesia is taken as the area of ancestral isolation of the cristatrix group in (1), this only adds one easterly range extension.

Geographical range (cristatrix). Oriental tropics to Sundaland and Palawan; also recorded from Ceram.

Habitat preference. The only specimen taken during recent surveys was at 1930m on G. Kinabalu.

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