Coronapelopia valedon Cranston & Krosch, 2021

Cranston, Peter S., Krosch, Matt & Baker, Andrew M., 2021, Molecular evidence for deeper diversity in Australian Tanypodinae (Chironomidae): Yarrhpelopia and related new taxa, Zootaxa 4949 (1), pp. 1-23 : 14-17

Coronapelopia valedon Cranston & Krosch sp. n.

( Figs. 4–6 )

urn:lsid:zoobank.org:act:45304FFC-043A-4DDE-A1ED-C21202D0BA99

[ Pentaneurini genus D Cranston 1996, 2010, 2019c]

Material examined (collected Cranston unless stated otherwise, deposited ANIC).

Holotype, slide-mounted in Euparal: P ♂, AUSTRALIA: New South Wales, Brown Mt. , Rutherford Ck., 36°36’S 149°47’E, 16.x.1990 (Cranston & Edward).

Paratypes: AUSTRALIA: Queensland, 4 Pe, Cape Tribulation, Oliver Ck., 16°08’37”S 145°26’21’’E, 22– 23.iv.1999; P ♂, Mt. Lewis N.P., Churchill Ck., 16°34’S 149°47’E, 1.xi.2012 MV FNQ12 CHT2 ; 4 Pe, Kenilworth State Forest , Bundaroo Ck., 26°41’S 152°36’E, 26.ix.1989 (Cranston & Edward); Pe, same except 27.xi.1989 (Cranston) .

New South Wales: 2L, L(P), Blue Mts, Grose Valley , Fairy Dell Ck., 33°35’S 150°15’E, site E0101, 18.xi.1992 ( AWT); Pe, Brindabella, Goodradigbee R., 35°23’54”S 148°44’51’’E, 4.i.2001; ♂, P ♂, 7Pe, as holotype [Pe to ZSM] .

Australian Capital Territory: Pe, Brindabella [Ranges], Blundell’s Ck., 35°22’S 148°50’E, 6-9.iv.1988; Pe, Corin, Gibraltar Falls, 30.i.2001, 35°28’S 148°55’E .

Description. Adult male (n=4–5, all teneral) body length ~ 2.3–2.5 mm, wing length undetermined. Colour apparently yellow-brown, scutal vittae mid-brown, scutellum darker brown. Antennal plume and legs pale.

Head. A.R. ~2.0–2.1, terminal flagellomere tapering, 3-4× as long as broad, with terminal strong seta 50 long ( Fig. 4A ); penultimate flagellomere 3.5× terminal flagellomere; eye bare, with 6 ommatidia long dorsomedial extension. Temporal setae 8-9 closely aligned as inner verticals, none dorso-laterally. Clypeal setae 16. Palp (n=1) clearly 5 segmented; 1 bare, 2-4 with long setae, 5 much less setose; lengths of 2–5: 23, 42, 74, 110, seemingly lacking sensilla clavata. Scape bare, pedicel with 1 lateral seta.

Thorax. Scutal tubercle absent. Antepronotal setae 1, fine; acrostichals ~15, uni-biserial between the vittae ending in anterior prescutellar field; dorsocentrals ~20, arising anteriorly in humeral field, multiserial in humeral area, uniserial between vittae, expanded posteriorly; supraalars 0; prealars biserial 8–9; scutellars 9–10 uniserial. Preepisternum bare.

Wing. Costa ending at apex of R 4+5, distant from wing apex, ending above midpoint between ends of M 1+2; and M 3+4; R 2, R 2+3 and VR not determinable on teneral wing. Membrane unpatterned, densely setose in all cells and all veins. Anal lobe rounded. Squamal setae 7–9.

Legs. LR 1 0.6–0.64, BV 1 1.9–2.2, SV 1 3.0–3.2; LR 2 0.7–0.72, BV 2 2.5, SV 2 3.2 LR 3 0.72–0.73, BV 1 2.2, SV 1 2.8. Tibial spur ( Fig. 4B ) lengths; P 2 15; P 3 15; without tibial comb. Claws very slender, slightly curved, distally pointed, simple. Pulvilli absent.

Hypopygium ( Fig. 4C, D ). Tergite IX microtrichiose without setae; “anal point” not evident. Gonocoxite 95 long, cylindrical, beset with very long (>125 long) setae on dorsal and lateral surface, extending well beyond flexed gonostylus; proximal dorso-medial surface with oval patch of mid-lengthed, dense, medially-directed setae. Gonostylus 78–80 long, very narrow but scarcely tapering, terminal spur 23 long, subapical seta inserted on inner margin 35 from apex ( Fig. 4D ). Phallapodeme not visible, sternapodeme inverted V-shaped.

Adult female unknown.

Pupa (n=10). Length 2.5–2.9 mm. Cephalothorax pale yellow including wing sheaths; abdomen TI with strong yellow-brown scar, remainder pale to yellow, with golden transverse apophyses.

Cephalothorax. Thoracic horn ( Fig. 5A ,flattened elongate ovoid; Corona large, occupying ~40–50, exceptionally 60% of length of thoracic horn, plastron plate subovoid, angled to long axis. Thoracic comb comprising 10–13 short tubules tending to fine spinules, longest 10 long ( Fig. 5A ), or seemingly absent. Basal lobe elongate lobe, 30 long. Thorax bare or micro-spinulose; without scutal or postnotal tubercle. Single antepronotal seta retracted from margin, only 1 weak precorneal seta; other thoracic setae indistinct.

Abdomen ( Fig. 5D ). Tergite I with scar, lateral muscle marks not visible.Abdominal microspinulation (shagreen) ( Fig. 5H ) of sparse, fine spinules not aggregated or linear. L setae taeniate on segments VII (4, clustered in posterior half) and VIII (all 5, evenly spaced). D setae: 3 on I, 4 on II, 5 on III–VII, absent on VIII; O-setae: 1 pair dorsal, 1 ventral, situated close to apophyses. Anal lobe ( Fig. 2D ) near rectangular ~2× as long as broad (270–300 × 26–32), with ultra-fine scattered spinules; borders smooth. Anterior macroseta thin (~5–6) after initial dilation compared to broader (10–12) posterior macroseta; macrosetae adhesive. Genital sheaths smooth, of male ~220, extending ~90–100% length of anal lobe, containing very long gonostylar setae. of female short (~70).

Larva (n=2). Body length 4.0– 4.8 mm, head capsule ( Fig. 6A ) length 550–590 µm, golden-yellow with narrow cephalic margin only slightly darker golden-brown; mandible golden yellow, ligula golden, grading darker in distal half, anterior parapod claws fine and pale, posterior claws broader, golden-yellow, simple (but all contracted), Capsule longish-oval, cephalic index ~0.75 (compressed). Cephalic setation ( Fig. 6A, I ): SSm slightly retracted on mola, VP with V9, V10 unaligned, equidistant in a triangle; dorsal pit (DP) close to S5, S7 close to S8.

Antenna ( Fig. 6A, C ) ~60% head length, 2.5× mandible length, segment lengths: 250–300: 100–105: 5: 3; A.R.: 2.7–3.2, ring organ at ~50%; basal segment ~8× as long as basal width, Blade bifid, broad outer branch 65, slightly shorter than or subequal to narrow accessory blade, extending to or slightly beyond antennal apex. Lauterborn organ thin, short, 4–5, subequal to segment 3 ( Fig. 6C ).

Mandible ( Fig. 6G ) gently curved, with bluntly tapering apical tooth, 90–105 long; short, rounded, non-projecting inner tooth, seta subdentalis arises from rounded non-extended mola.

Ligula ( Fig. 6E ) with 5 teeth in concave row, all teeth directed anteriorly; ligula broadened from midpoint; narrow area of muscle attachment occupying basal 8–10%. Paraligula bifid, with outer branch 50% length of ligula, inner shorter. Pecten hypopharyngis ( Fig. 6J ) with 10–12 upcurved lobe/teeth, increasing in length anteriorly (nearest to ligula).

Maxillary palp length 80, basal segment 52 long; ring organ at <20% from base; crown with well-developed setae and sensilla including 2–segmented b-seta with subequal sections.

Submentum ( Fig. 6I ) anteriorly with transverse ‘creases’ of light sclerotisation, more evident laterally than medially. Dorsomentum with darker sclerotised patch 10 long, bearing 3–4 small teeth; M appendage uncertain, vesicles not distinguishable. Pseudoradula 8–10 wide, essentially parallel-sided, densely micro-granulose without alignment, posteriorly without contact to ventral hypopharyngeal apodemes.

Abdomen. Anterior parapod claws simple, pale. Anal tubules not determined. Procercus yellow, bicoloured, paler posteriorly, ~3× as long as wide (85 × 30), with 8 anal setae of length 350. Subbasal seta of posterior parapod simple, ~200 long. Posterior parapods yellow. seemingly all simple (but contracted) subtended on parapod by subapical area of few fine spinules.

Etymology (Derivatio nominis). The species epithet valedon , derives from farewell (vale) to our late colleague ‘Don’ Edward who was associated with the first collection made, in eastern Australia although somewhat ‘out of range’ of this proud western Australian. To be treated as a noun in apposition.

Remarks. Coronapelopia valedon is an Australian endemic distributed along the eastern margin of Australia, from 18°S to 36°S, and apparently absent from Tasmania.

Figures

FIG. 4. Coronapelopia gen. n. Adults. Male. A, Antennal apex; B, Tibial spur, C, Hypopygium, left side, dorsal, right side stylised ventral/internal, D, Detail, gonostylus apex. Female. E, Antennal scape, pedicel, basal flagellomere. F. Genitalia dorsal; G. Ventral, left side detail. A–D, C. valedon sp. n., E–G, C. quadridentata sp. n.

FIG. 5. Coronapelopia gen. n. Pupa. A–C. Thoracic horn and comb; D, E, Dorsal abdomen; F, Tergite IV spinulation (‘shagreen’), detail; G–H. Male anal lobe. A, D, F, G. C. valedon sp. n., B, E, H, C. quadridentata sp. n., C, Pentaneura? cinerea Philippi.

FIG. 6. Coronapelopia gen. n. Larva. A, B, Head, left ventral, right dorsal; C, D. Segments 2–4 of antenna; E, F, Ligula, paraligulae; G, H, Mandible apex; I, J, Submentum, ventral, right side insert dorsal; K, Pecten hypopharyngis; L, Flattened claw of posterior parapod. A, C, E, G, I, K. C. valedon sp. n., B, D, F, H. L. C. quadridentata sp. n. Abbreviations: S5–S10 cephalic setae, DP – dorsal pit, VP – ventral pit.

FIG. 2. Yarrhpelopia Cranston, Pupa, Larva. A–C, Thoracic horns; D, E, Anal lobes (left side only); F–H, Submenta; I–K, Mandibles; L, ventral head; M, antennal apex; N, Ligula, paraligula; O, Pecten hypopharyngis. A, E, F, Y. norrisi, type locality; B, I, Y. norrisi var ‘’ST1’; D, G, Y. norrisi var. “genus D”; C, K–O, Y. ‘V20’. Abbreviations: S5–S10 cephalic setae, DP – dorsal pit, VP – ventral pit.