Protaustrosimulium amphorum 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 : 310-320

Protaustrosimulium amphorum Currie, Craig & Moulton. n. sp.

( Figs. 22–66 )

Description. Female (based on four reared specimens). Body ( Fig. 22 ): overall blackish brown; total length 2.3–2.5 mm. Head ( Fig. 24 ): overall markedly dark in colour; width 0.79–0.81 mm; depth 0.50–0.54 mm; postocciput not markedly hirsute with long pale hairs, frons divergent, not markedly narrow, dark brown–black; frons:head ratio 1.0:7.0. Eye: interocular distance ca. 0.1 mm; eye evenly dark red, ommatidia diameter 0.01 mm; ca. 26 rows across and 36 down at mid–eye. Clypeus: width 0.19 mm; shiny black, vestiture of sparse small hairs. Antenna ( Fig. 25 ): extended well beyond head margins; total length 0.56 mm; evenly blackish brown; pedicel narrowed basally slightly broader apically than flagellomere I, others angulate, proximal flagellomeres wider than long, little tapered to apex. Mouthparts: ca. 0.4× length of head depth; maxillary palp ( Fig. 26 ), total length 0.6 mm, evenly dark brown, palpomere II narrowed and slightly elongated, palpomere III with denser vestiture, palpomere IV smaller, V (apical) palpomere subequal to III; proportional lengths III–V palpomeres 1.0:0.7:1.1; sensory organ 0.33× length of palpomere III, opening moderate, 0.3× vesicle width; mandible ( Fig. 27 ) narrowed and finely pointed with ca. 50 poorly developed inner teeth, ca. 15 slightly larger outer teeth; lacinia with ca. 20 teeth on inner and outer edges; cibarium ( Fig. 28 ) with broad sclerotized cornuae, slightly sculpted apically, median gap lacking armature, shallowly V-shaped. Thorax: length 1.3 mm; width 0.4 mm; evenly blackish brown; pronotal lobe well developed with fine hair longer than those on scutum (even fine small hairs); scutellar depression with long black hairs; scutellum concolourous to scutum, vestiture of long black hairs; postnotum black; antepronotal lobe with dense patch of black hairs; proepisternum and forecoxa, essentially bare; pleuron and anepisternal (pleural) membrane dark yellowish brown, without hairs; katepisternal sulcus distinct and deep. Wing ( Figs. 29 , 30 ): very slightly dusky on apex and anal lobe, length 2.6–2.8 mm; width 1.3–1.4 mm; anterior veins dark; basal (bm) cell minute; a:b ratio 1.0:2.8; distal 2/3 of costa with mixture of spines and hairs, R s not divided; M 1 appearing double; CuA slightly sinuous; CuP markedly sinuous apically, not reaching wing margin. Haltere: stem grey, knob dark brown. Legs ( Fig. 31 ): all evenly blackish brown; hind basitarsus lacking ventral row of stout spines; calcipala moderately well expressed, slightly tapered, pedisulcus present as single wrinkle; tarsomere II short, 2.0× longer than distal width; claws ( Fig. 32 ), smoothly tapered, heel massively expressed, basal tooth moderately expressed, 0.25× length of claw, arising laterally on heel. Abdomen ( Fig. 33 ): abdomen dark brown/black, anterior segments slightly lighter; vestiture not markedly expressed, more so posteriorly; tergites markedly sclerotized, well discernable from remainder of dorsum, tergite II protruded centrally, wing-like laterally, III U-shaped, IV rectangular, V slightly larger and rounded VII, others broader. Genitalia: blackish brown; sternite VIII with distinct pigmented median region, dense vestiture of microtrichia, sparse hairs posterolaterally; spermatheca ovoid ( Fig. 34 ), smooth, darkly pigmented, internal fine spines (acanthae) sparse, clear area at spermathecal duct junction absent, pigment extended substantially down duct; genital fork ( Fig. 35 ) unusual, anterior arm substantial, slightly expanded apically, membranous lateral areas, lateral arms markedly short and broad, lateral apodeme extended anteriorly as edge of membranous region, lateral arm apodeme expressed as ridge, posterolateral expansions markedly developed, all well pigmented; hypogynial valves ( Fig. 36 ), median edges of valves slightly convex, not touching, markedly sclerotized, broadly rounded apically; cercus in lateral view distinct, rounded cone-shaped, anal lobes rounded, small, both darkly pigmented ( Fig. 37 ).

Male (based on four reared and two pharate specimens). Body: overall colour blackish brown including head and thorax ( Fig. 38 ); total length 2.4–2.6mm. Head ( Fig. 39 ): width 0.82 mm; depth 0.5 mm. Eyes: upper ommatidia blackish orange, not markedly enlarged, diameter 0.03 mm, ca. 15 across and 18 down; lower ommatidia black to blackish orange, diameter 0.014 mm, ca. 28 across, 33 down. Clypeus: black; width 0.16 mm; vestiture of sparse fine black hairs. Antenna ( Fig. 40 ): total length 0.55–0.57 mm; evenly blackish brown; scape short, pedicel spherical, flagellomere I longer than wide, remaining flagellomeres angulate and barely tapered apically, distal few flagellomeres occasionally aberrant. Mouthparts: insubstantial; length 0.3× head depth; maxillary palpus ( Fig. 41 ) 0.65 mm long, palpomere II slightly elongated, palpomeres III & IV subequal in length, III slightly swollen basally, palpomere V fine and elongated, proportional lengths of palpomeres III–V 1.0:0.9:1.5, sensory vesicle small, spherical, occupying 0.3× length of palpomere III, opening 0.33× vesicle width; lacinia finely expressed, with apical hairs; mandible with serrated apex. Thorax: length 1.0 mm; width 0.8 mm; lateral cervical sclerites well expressed; scutum not markedly domed, head angled anteriorly; postpronotal lobe concolourous with scutum, antepronotal lobe with patch of sparse fine dark hairs, proepisternum bare; scutum essentially black, vestiture of evenly sparse fine hairs, longer in scutellar depression; scutellum concolourous with scutum with long black hairs laterally, postpronotal lobe concolourous with scutum; pleurae dark orange, anepisternal membrane without hairs, katepisternum browner, sulcus distinct and deep. Wing: length 2.0– 2.3 mm, width 0.9–2.0 mm; as for female. Haltere: stem dark, knob dark orange. Legs: overall blackish yellow, hind leg with tibia and hind basitarsus expanded medially ( Fig. 42 ), ventral row of stout spines absent, calcipala small, 0.5× width of basitarsus apex, pedisulcus absent ( Fig. 43 ); tarsomere II 2.0× length of apical width; tarsal claw with truncated basal tooth and grappling pad of ca. 20 teeth ( Fig. 44 ). Abdomen ( Fig. 45 ): overall black, vestiture of markedly long hairs, more so anteriorly; basal scale (tergite I) black, hairs markedly black and long, extended to posterior of segment III; tergite II 2.2× wider than long, rectangular, remainder increasingly broad further posteriorly, more rounded; sternite I present, II absent, III and those more posterior rounded and hirsute; small pleurae present, concertinaed. Genitalia: smaller and heavily pigmented ( Fig. 46 ); gonocoxa 1.6× longer than basal width, vestiture of sparse long black hairs; gonostylus in lateral view not tapered, approximately 2.0× longer than basal thickness, strengthened along inner edge, three substantial short, blunt, apical spines ( Fig. 47 ); ventral plate markedly sclerotized and strengthened around edges, 1.6× wider than long, keeled, posteromedial apex slightly convex, shallowly concave anteromedially, vestiture of evenly distributed hairs, longer on keel ( Fig. 48 ), anterobasal arms markedly expressed and narrowed; parameral connections absent, parameres as triangular plates, strengthened anteromedially, tapered posteriorly and crenulated, four long parameral spines per side, one shorter, arrayed together medially; median sclerite well expressed and bifurcate apically; aedeagal membrane with dense microtrichia.

Pupa. Body: length 2.5–3.2 mm, ( Fig. 49 ), markedly pale yellow to colourless, cuticle smooth. Head: frons of female angulate, ratio of basal width to vertex width 1.0:1.5 and basal width to length 1.0:1.6 ( Fig. 51 ); that of male, ovoid and elongate, ratios 1.0:1.5 and 1.0:1.7 respectively ( Fig. 52 ); cuticle faintly patterned; only facial setae present, frontal setae absent, epicranial setae present, closely applied beside antennal sheath. Thorax ( Fig. 54 ): notum not markedly domed, with minute flattened tubercules, dorsal setae trichoid, short and curved. Gill ( Figs. 50 , 65 ): three short trunks arising directly from base, one flexed dorsally, the others ventrally and laterally, tubular, filaments finger-like, thin-walled, colourless, branching irregularly for total of 10; maximum length ca. 1.5 mm; form various, tubular along full length, or narrowed abruptly apically, or with apex ballooned ( Fig. 50 ); surface featureless apart from normal trabeculae. Abdomen ( Fig. 53 ): overall cuticle markedly thin, unpigmented and with poorly expressed armature; minute low clear tubercules; tergites II–IV extended ventrally to incorporate pleural region, tergite III only tenuously so, tergites I & II with fine hairs, tergites III & IV with small posterior hooks, tergites V & VI essentially bare, tergites VI–IX with fine minute spine combs; pleurites absent, pleural regions V–VII each with small hook; sternite VI & VII with hooks; segment IX with minute terminal spines, other setae exacerbated but not grapnel hook-like ( Fig. 55 ).

Cocoon ( Fig. 49 ). Slipper-shaped, constructed of fine loosely- or irregularly-woven silk covering abdomen and most of thorax; extraneous material from substrate incorporated into cocoon.

Larva. Body ( Fig. 56 ): length 5.9–6.2 mm, Colour mottled orange; expanded markedly at segment V, smoothly tapered to posterior, amphora-shaped in dorsal view. Head ( Fig. 57 ): length 0.74–0.76 mm, maximum width 0.52– 0.56 mm; distance between antennal bases 0.34–0.36 mm; overall medium brown, pigment surround antennal base extended posteriorly and medially to ecdysial line and along that; head spot pattern markedly developed and positive; anteromedial and posteromedial head spots forming distinct line, flanked by first and second anterolateral spots, posterolateral spots not as markedly expressed; head widest just posterior to the stemmata, narrowed smoothly anteriorly, convex posteriorly; ecdysial line slightly sinuous anterior of stemmata; cervical sclerites finely fused to posterior of apotome and laterally to postocciput. Antenna ( Fig. 58 ): extended well beyond labral fan stem; total length 0.56–0.58 mm, proximal article clear basally otherwise dark brown, medial article brown, distal article colourless, medial article markedly shorter than proximal article, distal article elongated and thin, proportional lengths of basal, medial and distal articles 1.0:0.3:2.2; sensory organs on medial article small, apical one elongated. Labral fan: stem subequal in length and breadth, lightly pigmented, ca. 57 markedly fine rays, length ca. 0.6 mm, mid-ray width 0.006 mm; microtrichial pattern with sparse long ones (0.007 mm), smaller microtrichia apparently absent. Mandible ( Figs. 59, 60 ): not markedly pigmented; brushes not markedly developed; outer and subapical teeth small and grouped closely with well-developed apical tooth; ca. 11 fine spinous teeth; serrations and sensilla markedly defined, serrations as two cones (variable between sides), sensillum as single spike; blade region straight and smooth. Maxilla ( Fig. 61 ): not markedly pigmented; palpus broad, 2.0× as long as basal width; not markedly separated from lobe, brush at base poorly expressed. Postgenal cleft ( Fig. 62 ): present merely as small notch; region well sclerotised; posterior tentorial pits distinct, small and oval; postgenal bridge evenly light mottled brown; posteroventral muscles spots large, oval, not obvious; ratio of hypostoma: genal bridge: postgenal cleft 1.0:2.0:0.2. Hypostoma ( Fig. 63 ): protruded anteriorly, teeth darkly pigmented; tooth 0 (median) slightly prominent, flanked by smaller tooth 1 (sublateral), the next (2) markedly smaller, the next (3) slightly larger, tooth 4 (lateral) subequal in length to tooth 0; teeth 5, 6, markedly small (paralaterals), others apparently absent; anterior ventral edge of hypostoma obscuring teeth 1 to 3; lateral serrations essentially absent; hypostoma sloped smoothly laterally; 4 or 5 fine hypostomal setae on each side; suboesophageal ganglion not pigmented. Thorax ( Fig. 64 ): dark orange anteriorly; pharate pupal gill with filament bases visible, curled clockwise (with head to the right). Prothoracic proleg: small, lateral sclerites elongated, as in Prot. pilfreyi (e.g. Fig. 18 ). Abdomen: segments I–IV distinct with pale intersegmental regions, mottled orange; expanded laterally at segment V producing an amphorashaped posterior, evenly mottled. Ventral tubercles: distinct, but not marked. Anal sclerite ( Fig. 66 ): distinct, Xshaped, finely expressed, interarm struts absent; dorsolateral accessory sclerites expanded, connected to finely expressed complete semicircular sclerite, variously connected at ventral midline. Rectal papillae: three simple lobes, well developed. Posterior circlet: unremarkable, numbers of hooks, ca. 100 rows, 11 or 12 hooks per row (total ca. 1,150).

Etymology. In reference to the distinct amphora shape of the larval posterior abdomen.

Types. Holotype ( Figs. 22, 23 ): pinned female, dried via Peldri™. Label data:- [Holo/type] [ Protaustrosimulium / amphorum ] [WESTERN AUSTRALIA / Deeside Coast Road/ creek, S34.4380° female symbol/ E116.3863°, alt. 183 m. / 9-ix-2014./ Coll. J.K./ Moulton, D.C.Currie.] [ANIC database No./ 29 026645].

Paratypes: Pinned:- one female, two males. Label data as for Holotype, but with [PARATYPE]. Female with [ ANIC database No./ 29 026646], males with [ ANIC database No./ 29 026647] and [ ANIC database No./ 29 026648]. Alcohol material. Two reared females and one male with pupal exuviae; two pupae, one with cocoon; four last instar larvae [ ANIC database No./ 29 026649]. Seven last instar larvae, numerous early pupae and cocoons, reared male and female, pharate pupae, numerous pupal exuviae [ UASM #/ 370906] .

Additional material. Slide mounts (UASM# 370921-0928).

Distribution ( Fig. 99 ). Western Australia: Churchman Brook, Canning Dam Rd., S32.1869° E116.1164°, elev. 282m., 8-ix-1996, Coll. J.K. Moulton. Deeside Coast Road, creek, S34.4380° E116.3863°, elev. 183m., 2 & 9-ix- 2014. Colls. J.K. Moulton, D.C. Currie.

Bionomics. Little is known about the biology of this species. The dates of collection, with larvae taken on the 2 nd September and pupae on the 9 th, indicate that this is an Austral-spring species specialized for intermittent streams, similar to other Gondwanan simuliids of Western Australia. The type locality is a small slow-flowing muddy stream (Fig. 98) typical of the Warren bioregion (aka Kauri Forest bioregion). Apart from the amphorashaped abdomen of the larva there is little unusual about the immature stage. Shape might indicate a preference for thin films of water, as noted for the Tahitian Simulium (Inseliellum) cataractarum Craig , where similar-shaped larvae inhabit madicolous flow (Craig, 2003). The feebly developed cocoon ( Fig. 49 ) and markedly reduced pupal armature ( Fig. 53 ) also point to slow-flowing streams being the preferred habitat. The number of hooks (ca., 1,150) comprising the circlet of the posterior proleg, however, indicates moderate flow, albeit less than 1.0 m/s ( Palmer & Craig, 2000).

The female has moderately small abdominal tergites and that, along with the sharply-pointed mandible, toothed on both sides, plus a moderate-sized sensory vesicle on the maxillary palp suggests that this species is capable of blood feeding. Nothing is known about host preferences, although the small size of the basal tooth perhaps suggests a predilection for mammals.

Remarks. Simuliids associated with Protaustrosimulium amphorum in the Deeside Coastal Road stream were Nothogreniera occidentalis (Mackerras & Mackerras) ( Craig et al., 2018b) and Ectemnoides faecofilus Moulton, Craig & Currie.

terebrans -group. Genital fork with laterally flattened anterior arm, lobe-like junction at lateral arms ( Figs. 81 , 95 ).

Constituents. Protaustrosimulium terebrans (Tonnoir) and Protaustrosimulium opscurum n. sp.

Figures

FIGURES 30. Protaustrosimulium amphorum. Female adult. Wing. Scale bar = 0.5 mm.

FIGURES 53. Protaustrosimulium amphorum. Pupa. Abdomen. 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 22–27. Protaustrosimulium amphorum. Female adult. (22) Holotype, habitus. Scale bar = 1.0 mm. (23) Holotype labels. (24) Frontal view of head. Scale bar = 0.2 mm. (25) Antenna. Scale bar = 0.1 mm. (26) Maxillary palp showing sensory vesicle (s v), mandible (mnd) & lacinia (lc). Scale bar = 0.1 mm. (27) Mandible apex. Scale bar = 0.05 mm.

FIGURES 28, 29. Protaustrosimulium amphorum. Female adult. (28) Cibarium. Scale bar = 0.1 mm. (29) Wing veins. Scale bar = 0.5 mm.

FIGURES 31, 32. Protaustrosimulium amphorum. Female adult. (31) Calcipala & tarsomere II Scale bar = 0.1 mm. (32) Claw showing heel (h) and basal tooth (t). Scale bar = 0.02 mm.

FIGURES 33–38. Protaustrosimulium amphorum. Female adult. (33) Abdominal tergites. Scale bar = 0.5 mm. (34) Spermatheca. Scale bar = 0.05 mm. (35) Genital fork. (lateral apodeme – l a). Scale bar = 0.05 mm. (36) Hypogynial valves. Scale bar = 0.1 mm. (37) Cercus & anal lobe. Scale bar = 0.05 mm. Fig. 38. Protaustrosimulium amphorum. Male adult. (38) Habitus. Scale bar = 1.0 mm.

FIGURES 39–44. Protaustrosimulium amphorum. Male adult. (39) Frontal view of head. Scale bar = 0.2 mm. (40) Antenna. Scale bar = 0.1 mm. (41) Maxillary palp, mandible & lacinia. Scale bar = 0.1 mm. (42) Hind leg. Scale bar = 0.2 mm. (43) Calcipala & tarsomere II. Scale bar = 0.1 mm. (44) Claw & grappling hooks (g h). Scale bar = 0.02 mm.

FIGURES 45–48. Protaustrosimulium amphorum. Male adult. (45) Abdominal tergites (t) and sternites (st). Scale bar = 0.5 mm. (46) Ventral view genitalia (cleared). Scale bar = 0.05 mm. (47) Gonocoxa (gc) & gonostylus (gs). Scale bar = 0.05 mm. (48) Basal arms (ba), ventral plate (vp), parameres (p) & spines (sp). Scale bar = 0.05 mm.

FIGURES 49–52. Protaustrosimulium amphorum. Pupa. (49) Cocoon & pupa. Scale bar = 1.0 mm. (50) Gill. Scale bar =0. 5 mm. (51) Female head capsule. Scale bar = 0.2 mm. (52) Male head capsule. Scale bar = 0.2 mm.

FIGURES 54, 55. Protaustrosimulium amphorum. Pupa. (54) Thoracic cuticle. Scale bar = 0.2 mm. (55) Abdominal segment IX. Arrows indicate terminal spines. Scale bar = 0.1 mm.

FIGURES 56–60. Protaustrosimulium amphorum. Last instar larva. (56) Habitus, dorsal view. Scale bar = 1.0 mm. (57) Dorsal view of head. Scale bar = 0.2 mm. (58) Antenna. Scale bar = 0.1 mm. (59) Mandible. Scale bar = 0.1 mm. (60) Mandible apex. Scale bar = 0.02 mm.

FIGURES 61–66. Protaustrosimulium amphorum. Last instar larva. (61) Maxilla. Scale bar = 0.1 mm. (62) Postgenal cleft. Scale bar = 0.2 mm. (63) Hypostoma. Scale bar = 0.05 mm. (64) Thorax showing pupal gill histoblast. Scale bar = 0.5 mm. (65) Pharate pupal gill. Scale bar = 0.2 mm. (66) Anal sclerite, accessory sclerites (a s), semicircular sclerite (s s) & circlet of hooks. Scale bar = 0.2 mm.

FIGURES 14–19. Protaustrosimulium pilfreyi. Last instar larva (Grampians; except Fig. 18). (14) Mandible apex. Scale bar = 0.05 mm. (15) Postgenal cleft. Scale bar = 0.1 mm. (16) Hypostoma. Scale bar = 0.05 mm. (17) Thorax showing pupal gill histoblast. Scale bar = 0.5 mm. (18) Anterior proleg (modified from Davies & Györkös 1988: 109). Scale bar = 0.1 mm. (19) Pharate pupal gill. Scale bar = 0.2 mm.

FIGURES 78–83. Protaustrosimulium terebrans. Female adult. (78) Abdominal tergites (Canobolas, 1916). Scale bar = 0.5 mm. (79) Hypopygial valves (Canobolas, 1916). Scale bar = 0.1 mm. (80) Hypopygial valves (Middle Creek). Scale bar = 0.05 mm. (81) Genital fork (Canobolas, 1916), apodeme (ap). Scale bar = 0.05 mm. (82) Spermatheca (Canobolas, 1916). Scale bar = 0.05 mm. (83) Cercus & anal lobe (Middle Creek). Scale bar = 0.05 mm.