Pteroptyx testacea (Motschulsky)

Pteroptyx testacea (Motschulsky) View in CoL

( Figs. 113−116 View FIGURES 113-116 )

Luciola testacea Motschulsky, 1854: 48 . Ballantyne & McLean 1970: 268. Calder 1998: 179.

Luciola testacea Motschulsky. Olivier 1885: 357 (misidentification). Baer, 1886: 132 (misidentification). Bourgeois 1890: 169 (misidentification). Lucas, 1920: (misidentification).

Pteroptyx testacea (Motschulsky.) View in CoL . Olivier 1902: 73; 1907: 56; 1913b: 55. (Misidentification). McDermott 1966: 117 (misidentification).

Pteroptyx testaceum (Motschulsky.) . Olivier 1910: 48 (misspelling).

Type. Syntypes.’ Indes orientales’. Six specimens mounted on a card, five face down of undetermined sex, the sixth a male mounted ventral side uppermost ( ZMMU) ( Figs. 113−116 View FIGURES 113-116 ) .

Diagnosis. Not identified in collections, and our conclusions based on colour pictures of three specimens mounted dorsal side uppermost (of indeterminate sex), black and white photos of some of the type series (taken in the 1960s), a drawing of a leg and ventral aspect of terminal abdomen (from Elida Davydova). With pale brown dorsum and black tipped elytral apices; without deflexed elytral apices; LO in V7 apparently entire (interpretation based on Davydova’s sketch Fig. 115 View FIGURES 113-116 ); posterior margin of V7 not obviously trisinuate, with rounded defined posterolateral corners and a wide apically acute MPP which is shallowly and narrowly emarginated; it is not possible to determine if a MFC is present from the photos.

Remarks. Motschulsky (1854) described a small species, L. testacea , with pale dorsum and black tipped elytral apices, elytral punctation in lines, and the last segment of the abdomen having a projecting triangular piece in the middle. No mention was made of deflexed elytral apices. The type specimens correlate with this description, however we cannot confirm the nature of the elytral punctation from the photo of the type.

Misidentification of this species in the literature appears to have begun with Olivier (1885) who redescribed L. testacea from a male and female taken in Sarawak, describing the deflexed elytral apices in the male.

Baer’s (1886) catalogue referenced L. testacea from Manilla. Bourgeois (1890) recorded a male and 3 females of L. testacea from Cochinchine, the male having deflexed elytral apices, and indicated wider occurrence of the species in Malacca and Singapore.

The genus Pteroptyx was established by Ernest Olivier (1902) for two species, L. testacea and L. malaccae Gorham. Only two features of the male, distinguishing it from other Luciolinae, were given: apices of elytra strongly deflexed, and terminal abdominal sternite with posterior margin strongly trilobed. Olivier did not designate a type species, and these two species were listed under Pteroptyx in alphabetical order. Olivier (1907: 56; 1910: 48, reference to Pt. testaceum ) and McDermott (1966: 117) are catalogue references only.

Subsequently Olivier (1911−12) described Pt. decolor from Borneo without a dark elytral spot, and having a yellow head (i.e. between the eyes), and brown tarsi, but he did not attempt to distinguish it from Pt. testacea . In 1913b he presented a somewhat confusing attempt to distinguish Pt. decolor and Pt. testacea , both from Borneo, by the totally pale body colour of Pt. decolor , while Pt. testacea was described with dark tarsi. He did not mention the apical black elytral marking in Pt. testacea , but did indicate that both species had elytral apices deflexed. It has not been possible to determine the specimens on which these references are based. Likewise it is impossible to determine the identity of Baer’s (1886) catalogue reference to L. testacea . It appears that all mentions of L. testacea subsequent to its original description are to a different species which has deflexed elytral apices in the male.

Lucas (1920) designated L. testacea as the type species of Pteroptyx . There is no evidence to suggest that Lucas (1920) examined the type series of L. testacea , and probably selected it as the type species as the first described of the two Luciola species that Olivier assigned to Pteroptyx . Lucas thus, as the designator of the type species, misidentified it as had Olivier, Baer and Bourgeois, following Olivier’s redescription.

Ballantyne & McLean (1970) in their revision of Pteroptyx considered “to our knowledge, all the presumed L. testacea specimens described subsequent to the original description do not conform morphologically to the holotype; therefore the identities of these later specimens is uncertain.” The only species of Pteroptyx that Ballantyne and McLean redescribed, from Borneo, was Pt. decolor , a pale species (i.e. without an apical black area on the elytra) thus largely consistent with L. testacea but distinguished by its very pale head. They also confirmed the identity of L. malaccae , and the presence of deflexed elytral apices in the male. Calder (1998) stated “Olivier did not verify the identity of the two species he based his genus on. The generic description clearly shows that his intention had been to distinguish species with deflexed elytral apices, but instead based his concept on misidentified specimens.”

Previous interpretations of L. testacea as the type species of Pteroptyx have been based first on a definition of the genus as having deflexed elytral apices in the male, and the belief that L. testacea also possessed that feature. The discovery that L. testacea , in being without deflexed elytral apices, did not conform to that definition suggested that another type species should be designated. However as we show here that Pteroptyx may well include species without deflexed elytral apices this situation has to be further reviewed (references below).

Up to this point we have been unable to obtain high resolution pictures of the ventral surface of L. testacea , and have been constrained in what comments we can make given that we are working from a few drawings, colour photos of the dorsal surface of three specimens of indeterminate sex, and a black and white photo of the ventral surface which was taken in the 1960s. The issue of L. testace a as the type species of Pteroptyx , and indeed its identity is ongoing. Luciola testacea has never been included in our analyses, as we cannot reliably identify it in collections and we had considered that deflexed elytral apices in the male were a necessary morphological character for a species to be placed in Pteroptyx . That definition of Pteroptyx has now changed. If we were able to include L. testacea in our analysis it would possibly group within the clade (I: Fig. 2A View FIGURE 2 ) with the other three species without deflexed elytral apices, separate to the clade (II: Fig. 2A View FIGURE 2 ) with deflexed elytral apices on which Pteroptyx is currently based. Thus we have found it necessary to widen the definition of Pteroptyx to include both clades with L. testacea and tentatively the three new species without deflexed elytral apices.

Additionally our analysis grouped Poluninius within the Pteroptyx clade with the three species without deflexed elytral apices (I: Fig. 2A View FIGURE 2 ). While we could have placed all the species in Clade I ( Fig. 2A View FIGURE 2 ) into Poluninius , the likelihood that L. testacea is also a member of that group, has led us to tentatively place them into Pteroptyx and retaining Poluninius as a distinct genus for the purposes of this paper. We strongly suggest that future studies investigate the composition of these genera by incorporating all 14 species of Pteroptyx especially L. testacea , and Poluninius species into a phylogenetic analysis. For these reasons we do not feel at this time it is necessary to advocate a change in the type species of Pteroptyx as was suggested previously ( Ballantyne & McLean 1970).