Ectemnoides umbratorum Moulton & Currie & Craig, 2018

Moulton, John K., Currie, Douglas C. & Craig, Douglas A., 2018, A New Genus, Ectemnoides, for Seven Species of Australian Gondwanan Simuliidae (Diptera) With Description of a Novel Form of Larval Attachment, Insect Systematics and Diversity 2 (4), No. 4, pp. 1-54 : 4-10

Ect. umbratorum (Tonnoir) , n. comb ( Figs. 1 –44)

S. umbratorum Tonnoir 1925: 238 (Original description, female only).

Cnephia umbratorum, Mackerras and Mackerras 1949: 385 (New combination. Assigned to terebrans species-group).

C. umbratorum, Mackerras and Mackerras 1950: 167 (Transferred to aurantiacum species-group).

C. umbratorum, Mackerras and Mackerras 1955: 104 (Description of possible larvae).

( Cnephia of authors) umbratorum, Crosskey 1987: 443 ( Prosimuliini , undetermined genus).

C. umbratorum, Zwick 1997: 49 (Description of new material, discussion of taxonomic placement).

‘ Cnephia ’ terebrans, Moulton and Adler 1997: 1907 . Not terebrans .

P. umbratora, Crosskey and Howard 1997: 18 , 117 (Unnecessary emendation. Prosimuliini , unplaced to subgenus, new combination).

P. umbratorum, Bugledich 1999: 329 (Compilation of data).

‘ Cnephia ’ umbratorum Tonnoir, Moulton 2000: 98 . 2003: 47 (Molecular analysis).

P. umbratora, Crosskey and Howard 2004: 10 ( Prosimuliini , unplaced to subgenus).

P. umbratora, Adler and Crosskey 2008: 26 (Transferred to Simuliini , unplaced to subgenus)

P. umbratora, Adler and Crosskey 2018: 30 (Unplaced to subgenus).

Ect. umbratorum (Tonnoir 1925) (New combination).

Adult Female (based on one paratype, plus four other specimens from ANIC, plus material from Zwick, Moulton, and Craig). Body ( Figs. 1 and 2 ): head and thorax overall dark brown, with abdomen dark brown anteriorly, vestiture yellow; total length 1.9–2.7 mm. Head ( Fig. 3 ): overall evenly dark brown; frons broad; upper ommatidia sometimes lighter; width 0.57–0.68 mm; depth 0.51–0.61 mm; postocciput dark brown, vestiture sparse; frons dark brown, essentially bare; frons:head ratio 1.0:4.6. Eyes: interocular distance 0.15–0.16 mm; ommatidia diameter 0.018 mm; ca. 37 rows across and down at mid-eye. Clypeus: width 0.24–0.26 mm; dark brown, vestiture of sparse fine hairs apically, lateral edges slightly angulate. Antenna ( Fig. 4 ): evenly dark brown; extended well beyond head margins; total length 0.61–0.81 mm; nine flagellomeres, scape small, pedicel angulate, slightly larger than flagellomere I, flagellomeres II–X subequal in size and shape, flagellomere IX bluntly cone-shaped. Mouthparts: substantial, ca. 0.5× length of head depth; maxillary palp ( Fig. 5 ), total length 0.55 mm, palpomeres I & II small, palpomere III ovoid, darker brown than remainder, not extended distally beyond articulation with palpomere IV, sensory organ spherical, 0.3× length of palpomere III, palpomere IV with apex extended laterally, palpomere V (distal) not markedly elongate; proportional lengths of III–V palpomeres 1.0:0.8:1.0; mandible ( Fig. 6 ) with ca. 15 outer and 34 inner even teeth; lacinia with 14 inner and 21 outer teeth; cibarium ( Fig. 7 ) central depression broadly U-shaped, cornuae not marked developed, lacking sculpture. Thorax: noticeably domed; length 1.1–1.2 mm; width 0.8–0.9 mm; pronotal lobe well developed, with longer hairs than on scutum, that overall with even sparse fine pale hairs, vittae visible in some lighting; scutellar depression with long coarse black hairs laterally; scutellum slightly paler than scutum, vestiture also of with long coarse black hairs laterally; postnotum slightly lighter than with scutellum; antepronotal lobe (propleuron) with long fine yellowish hairs, proepisternum bare; fore coxa bare; anepisternal evenly dark brown, membrane without hairs ( Fig. 10 ); katepisternum dark brown, sulcus distinct. Wing ( Fig. 9 ): slightly dusky apically as on anal lobe; length 2.7–3.0 mm; width 1.2–1.5 mm; a:b ratio 1.0:2.7; small basal cell present; veins yellowish, Rs not branched, but slightly thickened distally, closely applied to R 1, costa with spiniform setae, not markedly developed, interspersed with hair-like setae ( Fig. 8 ), M 1 thickened, not obviously double, CuA only slightly sinuous. Haltere: stem light orange, knob pale. Legs ( Fig. 2 ): bicolorous, medium brown and yellow, darker on posterior femora and tibiae; hind basitarsus with row of markedly stout spines; calcipala about as long as wide with dorsobasal notch ( Fig. 11 ); pedisulcus poorly developed (Tonnoir 1925: did not illustrate it. Mackerras and Mackerras 1949: show it as given here); tarsomere II 2.8× longer than distal width; claw ( Fig. 12 ), with main talon elegantly curved, slightly serrated on inner edge, basal tooth ca. 0.3× as long as claw, distinctly peg-like, well separated from claw and slightly off-set from line of claw, various, smaller on some claws, even on same leg, heel minute. Abdomen ( Fig. 13 ): basal scale grayish brown, vestiture not markedly elongated; segment II yellow, III darker, remainder dark grayish brown, tergites not markedly pigmented or sclerotized, vestiture of sparse small hairs, vestiture on pleurae moderately developed and yellow, increasingly so posteriorly. Genitalia: sternite VIII evenly pigmented medially, vestiture of rows of microtrichia, large strong hairs posterolaterally; hypogynial valves ( Fig. 14 ), broad, lightly pigmented, vestiture of microtrichia with scattered setae, median edges of valves straight to slightly divergent, not markedly strengthened on median edge, slightly flanged apically; genital fork ( Fig. 15 ) with stem narrowed, pigmented, substantial, knee bend at junction with lateral arms broadly expanded and angulate, lateral arms with distinct cone-shaped apodeme posterolaterally, lateral plates angulate; spermatheca ovoid, externally smooth, internal fine spines (acanthae) present, but hard to observe, no clear area at spermathecal duct junction, pigmentation continued for short distance along duct ( Fig. 16 ); cerci in lateral view bluntly rounded, occasionally with apical depression; anal lobes low, broadly rounded ( Fig. 17 ).

Adult male (based on a single damaged pharate specimen from Zwick material). Head ( Fig. 18 ). Wing. (not illustrated), length ca. 3.4 mm, width ca. 1.8 mm. Antenna ( Fig. 19 ): length 0.5 mm; evenly medium brown; flagellomere I longer than wide, flagellomeres II–VIII subequal in size, flagellomere IX slightly elongated, rounded apically Maxillary palp ( Fig. 20 ): light brown, length 0.4 mm, palpomeres III & IV subequal in length, palpomere V longer, proportional lengths 1.0:0.9:1.3; mandible and lacinia haired apically. Genitalia ( Fig. 21 ): gonocoxa narrow, 2.5× as long as maximum width, vestiture of sparse fine hairs; gonostylus ca. 3.0× longer than basal width, smoothly curved, vestiture of fine sparse hairs, one short apical spine; ventral plate 2.0× wider than length, broadly concave posteriorly, lobed laterally, broadly concave anteromedially; vestiture of coarse hairs; distinct central keel; basal arms narrowed, tapered smoothly; parameral connectors, plates and spines not observed; median sclerite well developed, expanded distally. Cerci well expressed.

Pupa (based on two partial exuviae plus damaged pharate male. Male from Acheron River, female from the Grampians). Body: length; male 3.5 mm ( Fig. 22 ) cuticle essentially colorless. Head: frontal plate of female bluntly ovoid and ratio of frons width to vertex width 1.0:1.5 ( Fig. 26 ); that of male narrowed with pointed vertex; ratio 1.0:1.8 ( Fig. 27 ), covered with barely visible minute clear tubercles; facial setae elongated and curled, frontal setae doubled, bifurcated. Thorax: anterior dorsal shield apparently smooth, but with small clear tubercles, dorsocentral setae long, substantial and curled apically ( Figs. 22 and 23 ). Gill ( Fig. 24 ): total length 2.6–2.8 mm; markedly elongated and fine, light brown; single basal trunk with fenestra enlarged and longer than typical—associated is a markedly thin-walled tubular structure, termed the ‘fenestral diverticulum’ ( Fig. 25 ); gill base bifurcating into two moderately long secondary trunks, further divided into 17 or 18 long thin filaments, with occasional shorter filament. Surface proximally pseudoannulated (i.e., annulations do not continue completely around the filament) to fully annulated, finely distally. Abdomen ( Figs. 28 and 29 ): cuticle covered with minute tubercles; armature not markedly developed; tergites I, II, with four finely curved hairs; tergite III with three finer curved hairs and two on the pleural region; tergite IV similar but lacking plural hairs; tergite V with hairs; tergites I–IV lacking other armature; tergite VI with anterior row of spine comb and two posterior hairs; tergite VII similar, but with one hair; tergite VIII with finer spine comb and two grapnel hooks; tergite IX with two terminal spines not markedly developed, but substantial and sharply tapered, not markedly curved; tergites II, III, IV extended ventrally onto pleural region, but separate from the respective sternites, segment V lacking pleurite, but with single substantial hair; segments VI, VII similar with two and one hair respectively; sternite II lacking armature; sternite III with four fine hairs; sternite IV with two substantial hairs and three branched hairs; sternite V with two substantial hairs and marked sockets, one single fine hair and one branched hair; sternite VI with single substantial hook and large base, one other moderately substantial spine-like hair and two finer ones; sternite VII with single spine and enlarged base; sternite VIII with two grapnel hooks; sternite IX with two fine posteriorly-directed hairs, two other smaller hairs and two grapnel hooks. Cocoon (based on single male pupa; Acheron River). Coarse weave, silk fibers not markedly thick; shapeless bag covering much of the abdomen; sparse material from substrate incorporated.

Larva (based on last instar larvae from Acheron and Grampians). Body ( Fig. 30 ): total length 5.5–6.3 mm; depending on habitat the larvae can range from almost transparent to grayish yellow. Head ( Fig. 31 ): evenly markedly pale with sclerotized structures dark; total length 0.8 mm, width 0.6 mm; distance between antennal bases 0.5 mm; antennal phragma markedly expressed posteromedially; anterior margins of head subparallel, posterior of the stemmata slightly convergent; apotome narrow, head spot pattern positive, but barely obvious; ecdysial lines well visible, essentially parallel and straight until extreme posterior of head, then rounded; cervical sclerites, small, separate from darkly pigmented, finely sclerotized postocciput; apotome with short stout secondary setae producing roughened spotted appearance ( Fig. 32 ), posterior third bare, genae also with such setae ( Fig. 37 ); suboesophageal ganglion lightly pigmented (as for Ect. faecofilus , e.g., Fig. 68 ). Antenna ( Fig. 33 ): markedly pale and hard to observe; extended to only half length of labral fan stem; total length 0.25 mm; basal antennomere short, medial and apical antennomeres subequal in length; proportional lengths of antennomeres 1.0:1.5:1.3. Labral fan: stalk thin and elongated, ca. 50 markedly fine rays, length 0.84 mm, mid-ray width 0.01 mm; microtrichia 0.008 mm in length, no distinct pattern. Maxilla ( Fig. 34 ): maxillary lobe cone-shaped, palp elongated, and curved, 4.0× as long as basal width; tuft of hair at base of palp not markedly expressed. Mandible ( Figs. 35 and 36 ): overall lightly pigmented and slightly elongated; brushes reduced; outer apical teeth poorly developed; apical tooth not markedly produced; subapical teeth not obvious; ca. 8 markedly cone-shaped spinous teeth; sensillum and serration present merely as fine spines posterior of slightly convex blade-like region. Postgenal cleft ( Fig. 37 ): well developed, deeply U-shaped, sclerotized anterolaterally of poorly expressed posterior tentorial pits, small posteromedial projection; postgenal bridge without stout setae; ratio of hypostoma, postgenal bridge and postgenal cleft 1.0:1.5:0.8; suboesophageal ganglion pigmented light gray. Hypostoma ( Fig. 38 ): unusual configuration, darkly pigmented; tooth 0 (median) and teeth 1, 2, 3 (sublateral) small, subequal and depressed below general line of remaining teeth, tooth 4 (lateral) massive and flattened apically; teeth 5–8 (paralaterals) teeth recurved toward tooth 4; lateral serrations poorly expressed; one main hypostomal seta on each side; 2 or 3 other small setae variously arrayed more basally. Thorax ( Fig. 40 ): prothorax grayish brown, remainder of thorax lighter; the mature pharate pupal gill with filaments directed ventrally then broadly posteriorly to produce a broad U-shaped structure with opening dorsal; one basal branch showing anteriorly. Prothoracic proleg ( Fig. 39 ): markedly elongated, lateral plates distinct and elongated V-shaped. Abdomen: evenly mottled medium yellowish gray—various—almost transparent in some populations; cuticle with hexagonal patterning ( Fig. 41 ). Ventral tubercles: absent. Anal sclerite ( Fig. 42 ): markedly reduced, anterodorsal arms absent, remainder simply two lightly sclerotized posteroventral arms, (as indicated by campaniform sensilla), clear cuticular ring around circlet of hooks present, well expressed adjacent to posteroventral arms, less so elsewhere. Posterior circlet: markedly directed ventrally; ca. 60 rows of hooks, 6 or 7 per row (total ca. 390).

Type Material

Holotype

Tonnoir (1925) stated that the holotype was in the Cawthron Institute (Nelson, New Zealand) and that three paratypes were in his possession. Mackerras and Mackerras (1949: 385) recorded that the holotype was in Canberra, as does Bugledich (1999) with that and other types in ANIC. The holotype was not available for our examination, so exact label data is unknown, but no doubt as for the paratype.

Tonnoir (1925) gave the type locality as Fern Tree Gully, Mt. Dandenong, (Melbourne), Victoria, 25. x. 1921. (ca. S37.8800° E145.3200° elev. 255 m). This site is southwest in the Dandenong Ranges National Park (east of Melbourne and adjacent to Upper Ferntree Gully suburb) and probably was Fern Tree Gully Creek. As are many of the earlier localities for Australian simuliids, the creek, albeit in a National Park, is now seriously impacted by human activities and there are no simuliids in the foul trickle of water exiting the Park. Tonnoir would weep!!!

Figures

Figs. 1–6. Ectemnoides umbratorum female. (1) Habitus, paratype (Mt. Dandenong). Pinned. Scale bar = 1.0 mm. (2) Habitus (Grampians). Alcohol. Scale bar = 1.0 mm. (3) Frontal view of the head,cleared (Narbethong).Scale bar = 0.2 mm. (4) Antenna (Narbethong).Scale bar = 0.2 mm.(5) Maxillary palp,mandible, and lacinia. Paratype. Scale bar = 0.1 mm. (6) Mandible (Acheron). Scale bar = 0.05 mm.

Figs. 7–11. Ectemnoides umbratorum female. (7) Cibarium (Acheron). Scale bar = 0.05 mm. (8) Wing veins (Acheron). Sc – subcosta; C – costa; R1 – radius; Rs – radial sector.Scale bar = 0.1 mm. (9)Wing (Acheron).A1 – anal; CuA,CuP – cubital; M1, M2, M4 – medial. Scale bar = 0.5 mm.(10) Anepisternal membrane,cleared (Grampians).Scale bar = 0.2 mm. (11) Hind basitarsus and tarsomere II (Narbethong). Scale bar = 0.05 mm.

Figs. 12–17. Ectemnoides umbratorum female. (12)Tarsal claws (Narbethong). Scale bar = 0.02 mm. (13) Abdominal tergites ((Narbethong). Scale bar = 0.5 mm. (14) Hypogynial valves, paratype (Mt. Dandenong). Scale bar = 0.1 mm. (15) Genital fork, paratype (Mt. Dandenong). Scale bar = 0.05 mm. (16) Spermatheca, paratype (Mt. Dandenong). Scale bar = 0.05 mm. (17) Cercus and anal lobe, paratype (Mt. Dandenong). Scale bar = 0.05 mm.

Figs. 18–21. Ectemnoides umbratorum pharate male (Acheron). (18) Frontal view of the head. Scale bar = 0.2 mm. (19) Antenna. Scale bar = 0.1 mm. (20) Maxillary palp, lacinia, mandible. Scale bar = 0.05 mm. (21) Genitalia, oblique ventral view. Original by H. Zwick, used with permission.

Fig. 22. Ectemnoides umbratorum pupal habitus. Insert: dorsocentral thoracic hairs. Original as for Fig. 21. Scale bar = 1.0 mm.

Figs. 23–28. Ectemnoides umbratorum pupa.(23)Thoracic cuticle (Acheron).Scale bar = 0.2 mm.(24) Gill, from histoblast (Grampians).Arrow indicates fenestral diverticulum. Scale bar = 0.2 mm. (25) Gill base.Arrow as for Fig. 24. Scale bar = 0.5 mm. (26) Head capsule, female (Grampians). f s – facial setae; fnt s – frontal setae.Scale bar = 0.2 mm. (27) Head capsule,male (Acheron).Incomplete.Abbreviations:as for Fig.26. Scale bar = 0.2 mm. (28) Abdominal armature (Acheron). Scale bar = 0.2 mm.

Fig. 29. Ectemnoides umbratorum pupal abdominal chaetotaxy and armature. Modified—original by H. Zwick. Used with permission. Scale bar = 0.5 mm.

Figs. 30–32. Ectemnoides umbratorum last instar larva (30) Habitus (Grampians).Scale bar = 1.0 mm.(31) Dorsal view of head (Grampians).Scale bar = 0.2 mm. (32) Cephalic setae.Scale bar = 0.05 mm.

Figs. 33–38. Ectemnoides umbratorum last instar larva (Grampians). (33) Antenna. Scale bar = 0.05 mm. (34) Maxilla. Scale bar = 0.05 mm. (35) Mandible. Scale bar = 0.1 mm. (36) Mandible apex. Abbreviations: a t – apical tooth; o t – outer teeth; sub t – subapical teeth; s – serrations and sensillum; s t – spinous teeth. Scale bar = 0.02 mm. (37) Postgenal cleft. Scale bar = 0.1 mm. (38) Hypostoma. Numbers indicate teeth. Scale bar = 0.05 mm.

Figs. 66–71. Ectemnoides faecofilus larva. (66) Antenna (Carey Brook). Scale bar = 0.1 mm. (67) Antenna (Rosa Brook). Scale bar = 0.05 mm. (68) Ventral view of head (Rosa Brook). Scale bar = 0.2 mm. (69) Mandible (Rosa Brook). Scale bar = 0.5 mm. (70) Mandible tip (Rosa Brook). s – serrations and sensillum. Scale bar = 0.02 mm. (71) Maxilla (Rosa Brook). Scale bar = 0.5 mm.

Figs. 39–42. Ectemnoides umbratorum larva (Grampians). (39) Anterior thoracic proleg. Scale bar = 0.1 mm. (40) Lateral view of pupal gill histoblast. Scale bar = 0.2 mm. (41) Abdominal cuticle. Phase contrast. Scale bar = 0.05 mm. (42) Posterior proleg, circlet of hooks, anal sclerite. Arrows indicate campaniform sensilla. Scale bar = 0.05 mm.