Protaustrosimulium opscurum Currie, Craig, Moulton., 2018

Currie, Douglas C., Craig, Douglas A. & Moulton, John K., 2018, A new genus, Protaustrosimulium, for four species of Australian black flies (Diptera: Simuliidae), Zootaxa 4521 (3), pp. 301-334 : 326-332

Protaustrosimulium opscurum Currie, Craig, Moulton. n. sp.

( Figs. 84–95 )

Cnephia sp. A Mackerras and Mackerras 1949: 385 (not Cnephia A Rothfels 1979: 522 or

Cnephia sp. A Pruess et al., 2000: 287).

Simulium nigrum Mackerras and Mackerras, 1949: 385 . Preoccupied

Paracnephia 'A' Mackerras & Mackerras 1949. Crosskey & Howard, 1997.

Description. Female (based on a single slide-mounted specimen ( Fig. 84 ) and literature description by Mackerras & Mackerras, 1949: 385–6). Body: Blackish, with dark brown legs. Head ( Fig. 86 ): frons:head width ratio 1:6.3. Eyes: interocular distance 0.13 mm; ommatidia diameter ca. 0.009 mm; ca. 36 rows down and across at mid-eye. Clypeus: not markedly enlarged, width 0.16 mm; black, vestiture of sparse fine black hairs. Antenna ( Fig. 87 ): extended well beyond head margins; total length 0.6 mm; nine flagellomeres, scape small, pedicel broad distally, flagellomere I broad and rounded, second flattened, remainder subequal in size to each other, except distal flagellomere cone-shaped; antenna overall not markedly tapered. Mouthparts: substantial, ca. 0.4× length of head depth, black; cibarium apparently with substantially sclerotized cornuae and broadly rounded medial depression; mandible markedly finely tapered, ca. 50 markedly small inner and 7 outer teeth ( Figs. 88 , 89 ); lacinia with 21 and 16 substantial teeth on inner and outer edge respectively; maxillary palp ( Fig. 88 ), elongated, total length 0.62 mm, basal two palpomeres small, palpomere III darker brown than remainder, narrowed basally, expanded at sensory vesicle, narrowed distally, subequal in size to apical palpomere V; palpomere IV extended slightly at distal junction; proportional lengths of palpomeres III–V 1.0:0.7:1.2; sensory organ narrow and elongated, 0.4× length of palpomere III, opening distinct, 0.7× vesicle width and elongated. Thorax: antepronotal lobe (propleuron) hairs absent or reduced to a few fine hairs at the lower margin. Wing ( Figs. 90 , 91 ): length 2.8 mm; width 1.3 mm; basal (bm) cell poorly developed; costa with well-developed spines, R s not branched, M 2 appears double for 2/3 lengtheffect produced by concentration of microtrichia, CuA markedly sinuous, a:b wing ratio 1:3, pigmentation at junction of r-m veins absent. Haltere: unknown. Legs ( Fig. 92 ): overall dark brown; hind basitarsus lacking ventral row of stout spines; calcipala distinct and slightly elongated; pedisulcus moderately developed, tarsomere II ca. 3× as long as apical width; claws large and black ( Fig. 93 ), smoothly curved, basal tooth small, triangular, as is heel. Abdomen ( Fig. 94 ): overall black, basal scale dark yellowish brown with vestiture of sparse long pale hairs; tergites markedly broader than long, tergite II markedly broad in dimensions, tergites III–V subequal in dimensions, those more posterior wider; overall vestiture black. Genitalia: hypogynial valves not observed; genital fork (partially reconstructed) ( Fig. 95 ) anterior arm markedly narrowed with rounded anterior expansion, lateral membranous areas, possible lateral apodeme at junction with lateral arms, but not clear, lateral arms broad, poorly sclerotized with slight knee-bend, apodeme as raised ridge at junction with posterolateral expansions, those pointed laterally, rounded medially; cerci in ventral view apparently ovoid, anal lobe with median notch; spermatheca not observed.

Adult male: Unknown.

Pupa: Unknown.

Larva: Unknown.

Type. The nomenclatural history of this species is rather muddled. Mackerras and Mackerras (1949: 385) referred to a Western Australian species named " Simulium nigrum " in an unpublished manuscript by Tonnoir. Tonnoir designated a holotype for that species and evidently deposited it in the School of Public Health and Tropical Medicine, Sydney, although the name was never validated as Tonnoir died ( Nicholson 1940: 139) and the manuscript never submitted for publication. Mackerras and Mackerras inadvertently took authorship of the name by listing it as a synonym of an entity they dubbed "Cnephia sp. A". Since the name " Simulium nigrum " that Tonnoir proposed was preoccupied by Simulium nigrum (Meigen 1804) and never published, it consequently has no formal standing. We found a single slide-mounted female of Tonnoir’s originally collected material in the ANIC—the specimen here designated as holotype of Protaustrosimulium opscurum .

Holotype: Dissected female mounted on glass slide in Canada Balsam. ( Figs. 84, 85 ). Label data:- [ S. nigrum . (scratched into glass)] [ Protaustrosimulium / opscurum ] [ANIC Database No./ 29 026695] [Australian/ National/ Insect/ Collection (green)] [Holo-/type (red)]. Two labels superimposed—upper [Cnephia/sp. A/ undecipherable mark, {F}, green spot/ Pemberton, W.A/ 28/8/26 A.J.N]. Lower label ( Fig. 85 ) [ Simulium / nigrum/ (Tonn. ms)/ {F} / (remainder as for superimposed upper label)]. Both in same handwriting. The collector was A.J. Nicholson, (see Waterhouse, 2000). Details of the lower label can be discerned by using strong back lighting, as used here ( Fig. 85 ). The name “ S. nigrum ” was presumably scratched into the glass slide by Tonnoir. Other labels are not by him and were probably applied by either Ian or Margaret Mackerras. The lower label was probably applied before the Mackerras’ settled on the name “Cnephia sp. A.”, as inscribed on the upper label.

Etymology. From the Latin ‘ opscurum ’ [= dark], to preserve the sense of Tonnoir's original unpublished description.

Distribution ( Fig. 99 ). Western Australia: Pemberton (ca. S34.4400° E116.0340°, elev. 127m.); Bridgetown (ca. S33.9600° E116.1370°, elev. 168m.).

Bionomics. Mackerras & Mackerras (1949: 386) noted that females were collected along with those of what is now referred to as Nothogreniera occidentalis, and may also have been biting humans. Nothing else is known about the biology of this species, except that collections were made in August.

Remarks. The specific distinctiveness of Protaustrosimulium opscurum has long been recognized. According to Mackerras & Mackerras (1949: 386) " There is no doubt that this species is quite distinct from any other Australian member of the family ”. In their Table 1: 380, they suggest that Prot. opscurum (as Cnephia sp. A) is “nr. terebrans "—a conclusion supported by the present study. A better understanding of relationships among Protaustrosimulium spp. will be gained when the immature stages of Prot. terebrans and Prot. opscurum are known.

The holotype of Protaustrosimulium opscurum from Pemberton, WA, is the only specimen of this species examined by us. The whereabouts of the Bridgetown, WA, material mentioned by Mackerras & Mackerras (loc. cit.) is unknown.

Figures

FIGURE 91. Protaustrosimulium opscurum. Female wing. Scale bar = 0.5 mm.

FIGURES 92–-95. Protaustrosimulium opscurum. Female adult. (92) Calcipala & tarsomere II. Scale bar = 0.05 mm. (93) Claw. Scale bar = 0.02 mm. (94) Abdominal tergites. Scale bar = 0.2 mm. (95) Genital fork (partially reconstructed). Scale bar = 0.1 mm

FIGURE 99. Distribution of Protaustrosimulium. (99) Map of southern portion of Australia.

FIGURES 84–88. Protaustrosimulium opscurum. Female adult. (84) Holotype, slide mount. (85) Overexposed scan of labels showing hidden original labelling. (86) Head. Partially reconstructed. Scale bar = 0.2 mm. (87) Antenna. Scale bar = 0.2 mm. (88) Maxillary palp, mandible, lacinia. Scale bar = 0.05 mm.

FIGURES 89, 90. Protaustrosimulium opscurum. Female adult. (89) Mandible apex. Scale bar = 0.02 mm. (90) Wing veins. Scale bar = 0.2 mm.