Philaccolilus kirana, Balke & Panjaitan & Surbakti & Shaverdo & Hendrich & Van Dam & Lam, 2022

Balke, Michael, Panjaitan, Rawati, Surbakti, Suriani, Shaverdo, Helena, Hendrich, Lars, Van Dam, Matthew H. & Lam, Athena, 2022, NextRAD phylogenomics, sanger sequencing and morphological data to establish three new species of New Guinea stream beetles, Alpine Entomology 6, pp. 51-64 : 51

Philaccolilus kirana sp. nov.

Figs 2A , 3A , 4 , 5C , 6A, B , 8A, B , 10A-D

Type locality.

Arfak Mts., Testega, Bird’s Head Peninsula, West Papua.

Holotype.

Male. Indonesia, West Papua, Testega, 1,210 m, 3.v.2015, -1,3686, 133,5908, UNIPA team (BH054) (MZB).

Paratypes.

(MZB, KSP, ZSM) 38 exs, same label data as holotype; 8 exs, Indonesia, West Papua, Testega, 1,100 m, 1.v.2015, -1,3827, 133,5967, UNIPA team (BH052).

Description of holotype.

Larger member of the genus. TL 5.6 mm; TW 3.1 mm.

Color. Body surface black except for orange head; anterior angle of pronotum very dark orange; elytron with broad, dark yellow subbasal band that reaching lateral margin; with small apical spot (Figs 2A , 3A ).

Structures. Hind margin of last ventrite emarginate in the middle (Fig. 8A ).

Genitalia. Median lobe of aedeagus as in Fig. 6A, B .

Female. Hind margin of last ventrite in the middle projected ("dwarf hat shape)" (Fig. 8B ).

Variation. Size variation of the paratypes is (N=27) TL 5.0-5.6 mm (av. 5.3 mm); TW 2.9-3.2 mm (av. 3.0 mm). The subbasal elytral band is more or less constantly developed; apical spot is not evident in some specimens. One specimen has the apical portion of the right elytron paler, orange, and there are two small orange postmedial spots on the left elytron.

Etymology.

Named after Maruscha Kirana Balke, daughter of first author. The species name is a noun in the nominative singular standing in apposition.

Comparative notes.

Distinguished from the other Philaccolilus species based on the following combination of features: body size; pronotum black; whole head orange; elytron usually with only a broad, dark yellow subbasal band reaching the lateral margin and usually small apical spot; shape of median lobe (except for P. intania Fig. 6C, D ).

Distribution.

So far only known from the type locality and nearby, situated in the southern Arfak Mts. of the Bird’s Head Peninsula of New Guinea (Fig. 4 ).

Habitat.

Collected from a small lower order stream hidden in dense montane forest (Fig. 10D ). Few specimens collected from a more or less sun exposed stream (Fig. 10A-C ), together with P. febrina .

Definition of the Philaccolilus ameliae complex

Philaccolilus ameliae Balke et al. (2000) was described from Morobe and Madang provinces in the eastern part of Papua New Guinea (Fig. 4 ), while the subspecies Philaccolilus ameliae weylandensis Balke et al. (2000) from much further west on the island, in the Weyland Mts. of Papua (Fig. 4 ). The subspecies was suggested based on the slightly narrower curvature of the median lobe in ventral view in Philaccolilus a. weylandensis ( Balke et al. 2000). We find that the shape of the median lobe shows slight variation among specimens and possibly populations (Fig. 7A-D, G-J ), and differences are indeed subtle. The discovery of Philaccolilus ameliae -like specimens on the Bird’s Head Peninsula and different areas in central New Guinea prompted an integrative taxonomic investigation of what we refer to as the Philaccolilus ameliae complex. We diagnose the complex as follows: moderately to larger sized beetles in the genus; pronotum black; whole head orange; elytral pattern dark yellow: narrow subbasal band with characteristic shape as depicted in Fig. 2D-H (basically three spots that can be isolated or more or less fused); a medio-discal dot or extended into longitudinal spot (in few specimens of P. ameliae extended posteriorly and reaching the postmedial band); postmedial band (of three isolated spots, rarely fused); an apical spot. The elytral color pattern is therefore variable, but constantly of the same general pattern and configuration (Fig. 2G ). The outer spot of subbasal band can reach the lateral elytral margin (Fig. 3C ), or hardly so (Fig. 3D ) or not at all (Fig. 3E ). Hind margin of male last ventrite truncate (Fig. 8C ), in the female ("dwarf hat shape)" (Fig. 8D ).

Figures

Figure 2. A-G. Dorsal habitus of Philaccolilus species in the P. ameliae complex, as well as P. kirana and P. intania, appendages mostly removed; brightness of some paler spots digitally slightly enhanced for clarity, without altering the basic color tone; H. schematic drawings of color pattern variation in P. ameliae species complex, with explanation of elytral pattern positions (modified from Balke et al. 2000).

Figure 3. Lateral habitus of Philaccolilus species; brightness of some paler spots digitally slightly enhanced for clarity, without altering the basic color tone. A. P. kirana; B. P. intania; C. P. weylandensis (Weyland Mts., basal lateral spot clearly reaching elytral margin); D. P. weylandensis (Digul River, basal lateral spot vaguely reaching elytral margin); E. P. ameliae (Waaf, basal lateral spot clearly isolated from elytral margin).

Figure 4. Distribution of Philaccolilus species in New Guinea. Dots - P. ameliae complex, stars - P. kirana and P. intania here described from the Bird's Head Peninsula.

Figure 5. Results of the genomic nextRAD as well as mitochondrial DNA CO 1 data sequencing of Philaccolilus species in New Guinea. A. P. febrina in the Bird's Head Pensinsula; B. P. ameliae and P. weylandensis in New Guinea main body; C. P. kirana and P. intania from the Bird's Head Peninsula (localities see A). Results of the structuring analysis of nextRAD data depicted as barplots, the CO 1 data as haplotype network, subs. = substitutions.

Figure 6. Median lobe of aedeagus of Philaccolilus species A, B. P. kirana; C, D. P. intania.

Figure 7. Median lobe of aedeagus of Philaccolilus species (left, lateral, right, ventral view) A, B. P. ameliae (from Brazza River); C, D. P. ameliae (paratype from Wau); E, F. P. febrina (from Tamrau Mts.); G, H. P. weylandensis (from Weyland Mts.); I, J. P. weylandensis (from Digul River).

Figure 8. Last male and female ventrite of Philaccolilus A, B. As in P. kirana and P. intania; C, D. As in P. ameliae, P. febrina and P. weylandensis. Not to scale. In C. with last and penultimate ventrites to illustrate the tuft of long golden setae on penultimate ventrite; E. P. febrina male in ventral view, not to scale.

Figure 10. Habitats of Philaccolilus species A-C. P. kirana and P. febrina locality BH 052; D. P. kirana BH 54; E. P. febrina BH 63; F. P. intania and P. febrina BH 60.