Ptilocerus spangenbergi sp. nov.
(Figs. 1, 2a, 3–12)
Type specimens: Holotype male, AUSTRALIA, Northern Terriotry, Pt Darwin, Jan 1938, in AM . Paratypes: 2 males, 8 females, same data as for holotype, in AM.
Other specimens: Queensland: 1 female, Atherton Tableland, J.G. Brooks, in AM; 1 male, Kuranda, 9.i.1951, J.G. Brooks, in AM; 3 females, 3 km NE Mt Webb, 15.03S 145.09E, 30.iv.–3.v.1981, A. Calder & J. Freehan Coll., in ANIC ; 2 females, Cooktown, 1.i.1964, G. Monteith, extracted from leaf litter, in QM; 1 female, Cape York, 1907, Elgner, W.W. Froggatt Coll., in QM. Northern Territory: 1 male, 5 km NNW Cahills Crossing (East Alligator R.), 12.23S 132.57E, 8.vi.1973, T. Weir & A. Allwood, right hemelytron missing, in ANIC ; 1 female, same data except 7 km NE by N of Cahills Crossing, 12.23S 132.56E, 9.vi.1973, R.I. Kitching, in ANIC ; 1 female, Cannon Hill via Jim Jim, 10.i.1972, F. Weerie, in QM; 1 female, Radon Creek, Mt Brockman, 12.45S 132.53E, 14.vii.1979, G.B. Monteith, “ QM Berlesate No. 103, sieved litter, rainforest (wet site)”, in QM.
Description. Body above and appendages with colour markings as in Fig. 1, markings of hemelytra particularly membrane variable as in Figs. 2a, 3 and 4, eyes dark brown, hemelytral membrane broadly irregularly pale along base, then banded along anterior margin alternating with fuscous, pale and fuscous bands, pale band not extending interior beyond second vein (Fig. 1); ocelli shiny.
Body and appendages covered with conspicuous setae except hemelytral membrane (Figs. 1, 3 & 4); trichome and associated structures as in Fig. 5. Setae on head, scutellum and margins of corium slightly thicker than those on antennae, legs and venter of abdomen, that are also longer (Figs. 1, 3 & 4).
Head. labium short, robust and tapered to point between fore coxae.
Fore wings. Anterior margin of hemelytra evenly curved particularly in basal third and apical third, apices of membranes of the two wings directed caudad and overlapping in resting position (e.g., Fig. 1), membrane with 3 longitudinal veins, apical part of vein M directed towards and almost reaching apical margin of membrane (Fig. 2a).
Abdomen. Venter with trichome spouted with thick tuft of setae and setae on surrounding area as in Figs. 5 & 6. Trichome structure includes, sternite II (i.e., visible I) with distinct median elevation, median projection and groove absent; arrangement of setae and hairs—group 1 paired, longitudinal patches of stout erect setae medially; setae on sternite II not distinctly scale like, row of setae on anterior margin of sternite III (i.e., visible II) incomplete at places. Dorsum with abdominal mediotergites and (dorsal) laterotergites as in Fig. 7, median area of intersegmental suture between terga IV–V and V–VI with paired scent scars (Figs. 7 & 8).
Female genitalia. Tergite VIII (t8) short, horizontal, lacking spiracles. Tergite IX (t9) triangular, heavily sclerotized. Valvifer 8 large, platelike; first valvula (va8) not distinct; gonoplac (gpc) as in Fig 9. Spermatheca (Fig. 9) symmetrical, simple, with apical bulb small, elongate ovate, heavily pigmented, basal duct tubelike and lightly pigmented (Fig. 9).
Male genitalia: Paramere (Fig. 10) sickle-shaped, curved portion provided with hair sensilla, apical one-fourth forming an elongate, apically bluntly pointed process. Phallus (Fig. 11): basal plate (bp) short, thick; phallosoma with a large, membranous basal anula (ba) provided with a pedicel (ped); phallotheca elongate, with a dorsal lightly sclerotized plate (dsp); endosoma tubular, with processes as follows: 1+1 struts subdivided into two portions: basal portions (strb) thick, slightly broadened towards apex, apical portions (stra) articulated to apex of basal portions of struts, thickened and curved basally, elongate, whip-like, narrowing toward apex (Fig. 11), far protruding from phallotheca.
Measurements (holotype male, paratype female, followed by ranges of other specimens examined in parentheses). Total length 6.6, 6.9 (6.0–7.4); maximum width 2.85, 3.20 (2.85–3.50). Head: Head length 0.69, 0.68 (0.60–0.85), width across eyes 1.15, 1.15 (1.03–1.24), interocular space 0.71, 0.69 (0.69–0.78), interocellar space 0.48, 0.51 (0.46–0.52), eye-ocellar space 0.23, 0.21 (0.15–0.23), eye length 0.27, 0.23 (0.23–0.27), eye width 0.23, 0.25 (0.18–0.25); length of labial segments: first visible 0.70, 0.69 (0.57–0.73), second visible 0.18, 0.18 (0.15–0.23), third visible 0.18, 0.23 (0.17–0.24); length of antennal segments: I, 0.34, 0.30 (0.30–0.45); II, 2.53, 2.40 (2.30–2.53); III, 0.30, 0.27 (0.25–0.35); IV, 0.34, 0.30 (0.30–0.42). Thorax: Pronotum median length 0.92, 1.00 (1.00–1.16), maximum width 2.45, 2.40 (2.07–2.41); scutellum length 0.39, 0.39 (0.35–0.50), width 0.92, 1.00 (0.80–1.00); hemelytral length 4.78, 5.06 (4.60–5.68); corium length 2.07, 2.07 (1.84–2.40).
Egg (Fig. 12) (based on one egg dissected out from a female paratype from Pt Darwin, Jan 1938, Northern Territory, Australia): Brown to dark brown; elongate ovate, widest at about mid length, posterior end gradually rounded, slightly more narrowly than opercular end which is roundly flat, operculum simple, no sculpturing or other ornamentation on chorion or operculum. Length 1.06, maximum width 0.64 mm.
Distribution. Restricted to northern areas of Northern Territory and Queensland.
Etymology. This species has been named in honour of Professor German Spangenberg of Agriculture Victoria and La Trobe University who, as scientist and dynamic science manager, has contributed immensely to agribiosciences research internationally. Over the years he has provided inspirational support to the development of biosecurity / biodiversity related taxonomy and diagnostics, and underpinning reference collections infrastructure in Victoria.
Notes. Ptilocerus spangenbergi sp. nov. is the first representative of the genus Ptilocerus from Australia.
The specimens examined in the present study exhibit considerable variation in the colour markings and other characters as follows. The specimens from Cahills Crossing, Cannon Hill and Radon Creek (NT) generally have slightly larger body size (7.3–7.4 mm), and have a generally paler membrane. The length and width (i.e., total size) of the pale patch in relation to the two fuscous patches (apical and basal) on the anterior margin of membrane may vary considerably: in some, the pale patch is about equal in length to apical but longer than the basal fuscous patch (Fig. 4); or may be about equal in length to both basal and apical fuscous patches; the width of the pale patch also varies, may or may not be distinct on the margin, and may or may not extend almost uniformly interior to the second vein M at about half of its width. Also, in some specimens the membrane anterior margin with apical 1/4–1/ 3 area has an elongate broad irregular fuscous patch that is not extending interior to the remaining width of membrane (Fig. 3), or may have fuscous patch almost uniformly extending interior, some with small indistinct pale areoles (Fig. 2).
Regarding its trichome, this new species appear to be similar to the type species, P. fuscus, but seems to lack scale-like setae on anterior area of sternum II (Fig. 5).
Ptilocerus spangenbergi sp. nov. has some similarities with P. immitis Uhler, 1896, from Japan and Taiwan (Rédei & Tsai 2011) in certain colour markings of the membrane, but differs from the latter in the shape of the anterior margin of the membrane (which in P. spangenbergi sp. nov. is similar to that in P. kanoi Esaki, 1931 from Taiwan (Rédei & Tsai 2011), and more extensive fuscous markings and often rounded light spots on the membrane.