Rakaphyllium exsectum (Zompro, 2001b) Cumming & Le Tirant, 2022

Cumming, Royce T. & Le Tirant, Ste ́ phane, 2022, Three new genera and one new species of leaf insect from Melanesia (Phasmatodea, Phylliidae), ZooKeys 1110, pp. 151-200 : 151

Rakaphyllium exsectum (Zompro, 2001b) comb. nov.

Fig. 9

Material examined.

Holotype (♀): "HOLO-TYPE; Rawlinson Mts. inland Huon Gulf. (Keysser).; Rothschild Bequest B. M. 1939-I.; Rawlinson Mt; Phyllium exsectum ♀ Zompro n. sp. HOLOTYPUS det. O. Zompro X.2000; BMNH(E) #845235" (NHMUK; Fig. 9 ).

Remarks.

This remarkable looking species is unfortunately only known from the singular holotype female from the little accessed Rawlinson Mountains of the Huon Peninsula (Fig. 5 ). Even in other phylliid species with prominent lobes on the abdomen, they pale in comparison to the unique habitus of this species, which likely evolved to mimic some strongly lobed host plant. Unfortunately, as this is the only specimen known and it lacks ecological data, nothing is known about a possible plant that the unique shape of this species may have evolved to resemble through advergent evolution.

Differentiation.

At present only the female is known for this species, no tentative males have been found which could represent the opposite sex. This species can be differentiated from its single other congenic by the elaborate lobed abdomen (although some Rakaphyllium schultzei -like females have been observed with slight lobes suggesting morphological plasticity within that species) or more reliably by the profemoral exterior lobe, which in Rakaphyllium exsectum comb. nov. is right angled (Fig. 9B ), versus Rakaphyllium schultzei which always has the profemoral exterior lobe roundly arcing from end to end without a distinct angle present (Fig. 6B ).

Distribution.

The type locality of Rawlinson Mts. on the Huon Gulf, Morobe Province, Papua New Guinea is the only record known at present (Fig. 5 ).

Figures

Figure 5. Distribution map noting all presently known records of Vaabonbonphyllium gen. nov. (denoted as star symbols) and Rakaphyllium gen. nov. (denoted as circle symbols) which were located and had data that could accurately be mapped. See Supplementary File 1 for full details for all records presented.

Figure 6. Rakaphyllium schultzei comb. nov. holotype female. Note that the holotype female is heavily damaged in several places, especially the abdomen which has numerous holes through which the background can be seen, this is not an artifact of image postprocessing A habitus, dorsal B right front leg, dorsal C associated data labels D details of head through thorax, dorsal. Scale bar only associated with A. Photographs by Arne Koehler (SDEI) and Mandy Schroeter (SDEI).

Figure 9. Rakaphyllium exsectum comb. nov. holotype female (NHMUK) A habitus, dorsal B profemora, dorsal C details of head through thorax, dorsal D genitalia, ventral E details of antenna, dorsal F associated data labels G details of head through thorax, dorsolateral. Scale bar only associated with A. Photographs A, F, G taken by Paul Brock (United Kingdom), other photographs taken by first author.