Nilotanypus haplochelus, Cranston & Krosch & Tang, 2022

Cranston, Peter S., Krosch, Matt N. & Tang, Hongqu, 2022, Verifying Australian Nilotanypus Kieffer (Chironomidae) In A Global Perspective: Molecular Phylogenetic And Temporal Analyses, New Species And Emended Generic Diagnoses, CHIRONOMUS Journal of Chironomidae Research 35, pp. 12-31 : 16-22

Nilotanypus haplochelus new species

http://zoobank.org/ 3F39CDE1-B48A-4643-9D49- A09EF31A9A6D

Type material: Holotype, Australia: P ♂, slide mounted in Euparal, Queensland, Mt. Lewis N.P ., Mt. Lewis , Churchill Ck ., 16°34’S 145°20’E, 6–7. iv.1997, leg. Cranston, ANIC . Paratypes, Australia: P ♀, 6Pe (on 2 slides), as holotype; P ♂, same except 8.x.2016, leg. Krosch, Bryant, Cranston, ( MV) FNQ16ML4.6 ; 3 Pe, same (non– MV).

Other material examined: AUSTRALIA: Northern Territory; 2Pe, Kakadu N.P ., Magela floodplain, Stoned Billabong , 12°38’S 132°53’E, 11.iv.1989; L, Gulungul Billabong, Gulungul Ck ., 12°39’S 132°53’E, 11.iv.1989; L, L(P), 10Pe, Djalkmara Billabong , 12°40’S 132°56’E, 10.iv.1989; 3L, Ranger, Magela Ck ., 12°40’39”S 132°56’10”E, –. iv.2005, leg. Humphrey, ( MV); ♂, Radon Springs , 12°45’S 130°47’E, 13–14.iv.1989; P ♂, Nourlangie Ck. , 12°49’S 132°45’E, 26.v.1988; Pe, Litchfield N.P., Florence Falls Ck., 13°06’S 132°26’E, 29.vii.2014, legs. Krosch & Cranston; Pe, Koolpin Ck ., 13°29S 132°35’E, 25.v.1988; Pe, Plum Tree Ck ., 13°32’S 132°26’E, 25.v.1989; L, L(P), 3P ♂, 3P ♀, Rockhole Mine Ck. , 13°30’S 132°30’E, 15.iv.1993, leg. Smith; P ♂, [same slide as Pe, N. haplochetus ], same except, 13.v.1993; 7L, L(P), Kakadu N.P., Kambolgie Ck. , 13°30’S 132°23’E, 6.ix.2017; L, Pe, 4♂, S. Alligator R., Gimbat spillway, Guratba [= Coronation Hill] 13°34’S 32°35’E, 19/20.iv. 1989; 3♂, 2Pe, S. Alligator R., Guratba [= Coronation Hill], 13°35’S 132°36’E, 4/ 5.vi.1989. Queensland: Daintree N.P ., Oliver Ck ., 16°08’3’’S 145°26’7’’E, 9–10. ix.1997, leg. McKie; Pe, Cassowary House Ck ., 1–2.x.2016, leg. Krosch & Cranston; 3Pe, Mossman, Rex Ck. , 16°28’S 145°19’E 19–20.x.1998, legs. Dimitriadis & Cranston; 7Pe, same except 10–11.iv.1997; Pe, same except 17–18.xii.1987, leg. Cranston; Julatten, Kingfisher Lodge , Sandy Ck ., 16°35’20”S 145°20’17”E, 6.x.2016 (to light); 6Pe, Shoteil Ck ., 16°56’S 145°37’E, 9–10. ix.1997, leg. McKie; 2Pe, Clohesy R. , 16°59’S 145°38’E, 7–8.ix.1997, leg. McKie; 2Pe, Mareeba , Davies Ck ., above falls, 17°01’S 145°35’E, 11–12.iv.1997; Pe, same except 19–20.vi.1997; same except 27–28.viii.1997 [same slide includes Pe, N. ctenochelus ]; Pe, 20 km E . Mareeba , Davies Creek N.P ., [~ 17°01’S 145°35’E], drift, 14-15. vi.1993, legs. M & B. Baehr; det. M. Spies, 2022 ( ZSM); P ♂, Danbulla N.P., Kauri Ck. , up from day–use area, 17°08’S 145°35’E, 9.ix.2018, leg. Krosch, ( MV); 13Pe, Bartle Frere , Junction Ck ., 17°16’S 145°55’E, 27–28.viii.1997; P ♀, 3Pe, Koombooloomba N.P. , Nitchaga Ck. , 17°49’45”S 145°33’50”E, 12.x.2017, leg. Krosch & Bryant; P ♀, Koombooloomba Ck. , nr dam, 17°50’16”S 145°35’16”E, 12.x.2017, leg. Krosch & Bryant; 3P ♂, 2P ♀, Ravenshoe, The Millstream , Cemetery Rd ., 17°36’50”S 145°28’40”E, 12.x.2016, leg. Krosch & Bryant, ( MV); Pe, same except 17°36’51”S 145°28’39”E; 3Pe, Palmerston N.P ., Tchooratippa Ck. , 17°37’S 145°45’E, 8–9.iv.1997; Pe, Herberton, Carrington Falls Ck. , 800 m a.s.l., 17°19’S 145°27’E, 9–10.iv.1997; 2Pe, nr Cardwell, 5–mile Ck., 18°19’S 146°03’E, 1– 4.iv.1997; Lawn Hill N.P. , Indarri Falls , 18°42’S 138°29’E 16.v.1995; 2Pe [on slide with 5 Pe N. ctenochelus ] Paluma, Birthday Ck ., 18°59’S 146°10’E, 25–26.iii.1998; 2L, Camp Ck. , 18°58’S 146°09’E, 21.ix.2008, leg. Krosch & Bryant; P ♂, S. Paluma, unnamed Ck. , 820 m a.s.l., 19°01’S 146°13’E, 25–26.iii.1998; Pe, Eungella N.P ., Mt. Dalrymple track., Cattle Ck ., 21°02’S 148°35’E, 950 m a.s.l., 22.iii.1998; Pe, Fitton Hatch Gorge , 200 m a.s.l., 21°05’S 148°37’E, 22.iii.1998; Pe, U. Brisbane R., Mount Stanley , 26°42’S 152°13’E, 19.i.1991; L( P), 3P ♂, Bunya, n. Brisbane , Carter Court , South Pine R. , 27°21’S 152°56’E, 21.iii.2013, 22 m a.s.l., leg. Krosch & Bryant; same except 5L, L(P), 21.x.2021; P ♀, Mt. Barney N.P ., Seidenspinner Rd , Mt. Barney Ck. , 28°14’S 152°44’E, 21.iii.2013, 176 m a.s.l., leg. Krosch. New South Wales: P ♂, U. Clarence R. , Gaya–Dari , 28°44’S 152°47’E, 20.i.1991; Pe, Chaelundi S.F ., Chandlers Ck ., 30°2’22”S 152°29’26”E, 11.iv.1996; L, Bellinger R. , 3 km W. Thora [~ 30°25’S 152°45’E], 1.xii.1990, leg. M. Baehr [“prep. F. Reiss, det. E. Stur ”] examined by M. Spies, 2022 ( ZSM); 2P ♂, 1♀, New England, Cathedral Rock N.P. , Sphagnum swamp drain, 30°26’42”S 152°16’.00”E, 13.iii.2017, ( MV); P ♀, Wollemi N.P. , Newnes , Wolgan R. , 33°13’16”S 150°13’22”E, 10.iii.2017; Pe, Morton N.P. , Corang R. , 35°15’S 150°06’E, 25.iv.1994; L, Brooman, Clyde R. , 35°30’23”S 150°13’27”E, 10.ii.2009; Pe, Shoalhaven R. , Hillview , 35°11’S 149°57’E 17.iii.1992; Pe, Warri Bridge, Shoalhaven R. , 35°21’S 149°44’E, 31.iii.1991; Pe, same except 17.iii.1992; 2Pe, Currowan S.F. , Cabbage Tree Creek , 35°34’S 150°02’E; Pe [same slide includes Pe N. ctenochelus ] Brindabella, Goodradigbee R. , 35°23’54’’S 148°44’51’’E, 4.i.2001; L., Captains Flat, Molonglo R. , 35°35’S 149°28’E; Pe, Kosciuszko N.P. , Yarrangobilly R. , 35°39’S 149°28’E, 14–15.i.1991; P ♂, 2Pe, S.E. Araluen , Deua R. , 35°45’S 149°57’E, 29.iii.1990; 2Pe, Wallagaraugh Ck. , 37°15’S 149°41’E, 13.i.1994; Pe, S.E. Cooma, Brown Mt., Rutherford Ck. [~ 36°36’S 149°47’E] 11.xi.1961 (Brundin), det. M. Spies, 2022 ( ZSM).

Australian Capital Territory ( ACT). 2L, Cotter R., 1.ii.1989. Victoria, Wodonga, Middle Ck ., Kiewa Valley Highway , 36°10’S 146°56’E, 3.iv.1990, leg. Cook; P ♀, U. Tambo R. , 36°59’S 147°51’E, 8.iii.1990, leg. Hortle.

Western Australia: P ♂, Hammersley Range N. P., Fortescue R. , Crossing Pool , 21°34’22”S 117°05’02”E, 24.iv.1992, leg. Smith ; 3Pe, Millstream Chichester N.P. , Fortescue R. , below Homestead , 21°33’S 117°03’E, 24–25.iv.1992 ; Pe, Circular Pool , Fortescue Falls , 21°28’S 118°33’E, 23–24.iv.1992 ; P ♀, Richenda Gorge , 17°27’09”S, 125°26’07 ̋E, 10.v.1995, leg. Smith ); P ♀, Kimberley, Upper Durack R. , 16°52’33”S 127°11’43”E, 8.v.1995 (leg. Smith); Kimberley, King Edward R. , 14°53’S 126°12’E, 5–6.v.1992 .

Etymology: From Greek, haplos = simple, chelus = claw, recognising all larval posterior parapod claws are simple and none are comb-like.

Diagnostic characters. See below, under Nilotanypus ctenochelus .

Description

Male (n=12, including pharates). Total length 1.4– 1.8 mm. Wing length 750–950 μm. Overall brown, legs paler, abdomen with slightly paler intersegments.

Antenna. With 14 flagellomeres, total length 492– 560, terminal flagellomere 40-50 long, with angled apex, straight (not offset), separated indistinctly from penultimate (13th) flagellomere ~160–192, 4–5 × length of terminal flagellomere, apical 2 flagellomeres subequal to 5.5 (5–6) preceding segments. AR 0.49–0.57; terminal seta 50–70 long. Scape bare, pedicel with 2 setae.

Head. Eye ( Fig. 1A ) microtrichose, dorsomedial extension 8–9 ommatidia long, slightly tapered and angled, 3–4 ommatidia wide. Frontal setae 2, ~100 μm, 7–9 uniserial temporal setae, with slight gap separating 2 outer verticals ( Fig. 1A ). Clypeal setae 14–18. Palp (2–5) 25–38; 50–63; 100–110; 75–110.

Thorax ( Figs 1E–G ). With uniserial tuberculose mesonotal margin, smoothly curved with posteromedian projecting small sense organ ( Fig. 1G ); 2–4 lateral antepronotal setae; ~16–25 unevenly uni-biserial acrostichals; ~15–24 dorsocentrals, biserial anteriorly, uniserial from midpoint; separated posterior dorsocentral / prescutellar, 8–11 prealars in anterior and posterior clusters; 1 supra-anal; scutellars with posterior-most row of 8 uniserial strong setae, with up to 20 shorter to much smaller setae anteriorly.

Wing ( Fig. 1H ). Hyaline, all veins pale, including crossveins, membrane and all veins densely setose; costa (C) extends to apex of R 4+5, strongly retracted from wing apex, and proximal to end of M 3+4; R 1 and R 4+5 widely separated, R 2+3 absent or at most, weakly indicated; R 4+5 runs close to costa. Crossvein vertical. Brachiolum to crossvein 160– 200, brachiolum to costa termination 500–670, costa terminal to wing tip 210–250. Squama with 16–20 uniserial setae,

Legs. Mensural: P 1 138-162, 90–118, 88–98, 28–38, 20–32, 25–35, 22–26, LR 1 0.70–0.86, BV 1 2.79–3.14, SV 1 2.86–3.02; P 2 165–230, 105–125, 155–178, 58–70, 40–52, 30–35, 30–33; LR 2 1.34– 1.42, BV 2 1.3–1.7, SV 2 2.71–2.88; P 3 150–192, 125–172, 140–192, 75–88, 55–70, 38–43, 27–30; LR 3 1.07–1.28, BV 3 1.70–2.03, SV s 2.02–2.53. Tibial spurs ( Figs 1I, J ) 1, 1, 1, each narrow, slightly curved, 30–40 long with basal fine divergent spines (‘hairs’), without lateral comb-like teeth; tibial comb on P 3 comprising 7–8 curved spines ( Fig. 1J ) 25–30 long. One pseudospur (50 x 3) subapical on Ta 1 on P 1 on most specimens; a single specimen also has a shorter (20–25 x 2) pseudospur on Ta 3 and Ta 4; P 2 with pseudospur on Ta 3 and Ta 4 (missing on 50% specimens; if present, shorter, poorly differentiated); P 3 with no pseudospur. Claws simple, gently curved, distally rounded, with strong basal rounded lobe. Pulvilli absent.

Abdomen. Setae at least as long or longer than segment, in more or less anterior and median transverse rows, on tergum and sternum.

Hypopygium ( Fig. 1K ). Tergite IX posteriorly with 6 or 8 aligned long setae; proctiger rounded. Gonocoxite squat, externally bulging, 65–70 long, maximum width 38–50, microtrichose, laterally with extremely long posteriorly-directed setae, 250–330 long, filling pharate pupal genital sheaths, setose on dorsal and lateral surface, with slightly differentiated dorso-medial cluster of dense medially-directed fine setae, posteromedian dorsal surface with stronger medially-directed setae with strong tubercle bases that give appearance of a small lobe. Gonostylus 40–52 long, initially broadened (7–8) then tapering and gently curved to 3 wide apex; weakly microtrichose with 3–4 mid-length setae on outer surface, 3 on inner and 1 subterminal; without any carina; megaseta at subapex of gonostylus, slender (5–7 long, 1–1.5 wide), angled relative to direction of apical gonostylus ( Fig. 1K ). Gc:Gs ratio 1.66–1.88. Phallapodeme strong, sternapodeme shallow arched.

Female (n=4, pharate/teneral). Total length ~ 1.5– 1.8 mm, wing length ~500–580 μm. Overall brown, abdomen with slightly paler intersegments.

Antenna. With 12 flagellomeres, total length 155– 260, terminal 42–61, with tapered blunt apex; AR [0.20] 0.32–0.36; lacking differentiated terminal seta, cluster 40–50 long. Pedicel with 4 setae, scape with 3–4 setae.

Head ( Fig. 1B ). Eye microtrichose, dorsomedial extension tapered, of 4–6 ommatidia long. Frontal setae 3–4, 110 long, aligned dorso-ventral, contiguous (at right angles) with 7–8 long uniserial temporals. Clypeal setae 16–22, ~100 long. Palp (1–5) 21–38; 25–40; 40–55; 60–75; 66–135.

Thorax. With weakly tuberculose anterior margin and small posteromedian scutal sense pit (possibly absent in some). Setal pits (and likely setae) in each location (ac, dc, pa, scts) variable not bimodal in size, originating either from pale longitudinal band, or from paler circular areas: with 1–2 lateral antepronotal setae: 17–22 acrostichals +/- biserial throughout, with isolated posterior dorsocentral / prescutellar, 17–22 unevenly biserial dorsocentrals, 7 prealars separated into anterior 3–4 and posterior cluster of 2–3; 1 supra-anal; scutellum posteriorly with 8 uniserial strong setae, more anteriorly with up to 30 short, finer setae.

Wing. Apical marginal setae up to 80 μm. Squama with 8 uniserial setae.

Legs. No measurements calculable. Tibial spurs 1, 1, 1, and comb on P 3 apparently as in male. Claws simple, gently curved, distally rounded, with strong basal rounded lobe. Pulvilli absent.

Abdomen. Each tergite with 2 transverse bands (anterior and median) of strong setae and small lateral cluster.

Genitalia ( Figs 1M, N ). Gonocoxapodeme VIII indistinct. Gonapophysis VIII solitary simple microtrichose lobe covered only with short setae. Gonotergite IX weakly protruding, without setae. Coxosternapodeme strong, dark, curved. Notum thin, 40–45 long, subequal to seminal capsule, posterior part of rami 40–45 long. Three hyaline, globular, seminal capsules, 35–40 diameter, without distinct neck; spermathecal ducts 130–140 long, dilate prior to narrowing before common ending. Anterior vagina with short spine seemingly associated with mesal end of gonocoxapodeme VIII ( Fig. 1N ). Cerci squat, small, 20–25 by 15–18.´

Pupa (n=10). Small, total length 1.4–1.9 mm.

Cephalothorax. Thoracic horn ( Fig. 2A ), flattenedtubular, sparsely spinose, 120–140 long, 4–4.5 x as long as maximum breadth, with initially narrow atrium dilate distally to fill ~90% of lumen; ovoid corona 55–62 long. Thoracic comb uniserial row of ~9–12 apically rounded tubercles, 8–12 (longest) diminishing laterad. Basal lobe 25–32 wide, 25–30 high, domed. Thorax weakly granular at most; wing sheath smooth, nose shallow or absent.

Abdomen ( Fig. 2D ). Tergites with short tubercles (2–3 long) aligned in transverse rows of predominantly triplets on tergites, pleurae and sternites, absent from apophyses and scar marks. Tergite I with pigmented scar. Setation: ‘O’ setae on all tergal and sternal transverse apophyses except for VIII, ‘D’ setae seemingly short, 4 characteristically aligned anterior to posterior with 2 sensilla, ‘L’ setae 1–2 per segment, when 2, one dorsal, one ventral, none taeniate on VII; taeniate LS only on VIII, all 5 evenly distributed in posterior 60% of segment. Posterior SVIII with linear-aligned 21–30 subapical spinules, 4–6, essentially uniserial and continuous in male, multiserial, slightly shorter and medially interrupted in female. Anal lobe ( Figs 2D, E ) in both sexes 125–135 long, 140–155 wide, bare, smooth on outer or inner margin, terminating with recurved hyaline blunt hook; anal setae adhesive, with maximum breadth of AL 1 seta narrower than AL 2 (4–5 versus 11–15 wide). Genital sacs dimorphic, male tapering, 250–300, 2× anal lobe; in female bluntly rounded, 0.5× anal lobe length. Genital sacs basally spinulose in both sexes.

Larva (n=12). Total length 2.5–2.7 mm. Head capsule length 330–380, max. width 170–240, cephalic index 0.50–0.63. Pale yellow with mandible, ligula and occipital margin slightly darker yellow to mid-brown.

Head.

Antenna ( Figs 2H, I ). Basal segment 130–148, 2nd 41–46, 3rd and 4th 4–5 long; AR 2.9–3.5, ring organ flush, at 68–75% from base; style and Lauterborn organ ~4 long; blade and accessory blade subequal to flagellum ( Fig. 2H ); antenna / mandible ratio 3.8–4.1.

Mandible ( Fig. 2J ). 47–52 long, seta subdentalis arising on strong distal molar projection (‘tooth’), proximal to rounded inner tooth.

Ligula ( Fig. 2K ). 42–48 long, 2.5 × as long as apical width, narrowed in middle; with 5 teeth, central tooth slightly broader and extending beyond outer teeth. Muscle attachment area weak. Paraligulae bifid, 32–36 long slender; 2/5 length of ligula; outer point at least 2× as long as inner. Pecten hypopharyngis ( Fig. 2K ) with 5-6 teeth, innermost tooth largest and directed antero-medially, remainder subequal and directed anteriorly.

Maxillary palp ( Fig. 2L ). 27–35 long, ring organ large ~70% from base, longest component of apical crown 14–16 long.

Mentum and M appendage . Dorsomentum without teeth, a sclerotized complex each side of base of M appendage , connected by ridges to ventromentum and ventral region of premento-hypopharyngeal complex, from which labial vesicles arise apically; dorsally with anteriorly directed tooth on each side. Ventromentum separated from M appendage by a fold. Pseudoradula finely and uniformly granulose, broadened near base.

Submentum / anterior gula ( Fig. 2M ). Straight with weak transverse ‘creases’ of paler cuticle. V9, V10, VP near longitudinally aligned, SSm posteriorly retracted; dorsal pit (DP) present, S7 well separated from S8, S5 retracted posterior to S8 ( Fig. 2F ).

Abdomen. Anterior parapods 170–200 long, fused from base, divided only subapically (90% of length). Each claw cluster comprising many simple claws, up to 30 long, mostly simple, some with hyaline outer including 4-6 short combs amongst simple basal spinules. Posterior abdomen ( Fig. 2O ) with parapod 250–275 long, near midpoint bearing isolated ventral 100 long spine; claws pale, variable in size and shape, several with hyaline carina, none pectinate lacking even fine spinules on inner margin. Procercus hyaline anterior, darker posteriorly, 26–35 long, 9–12 wide, with short darkened spur at the base; near midpoint bearing procercal seta 10–12 long, apically with 7 anal setae length 210–240. Supraanal seta strong, 220 long. Anal tubules narrow, tapered, elongate, at least as long as posterior parapods (>250), but difficult to measure precisely.

3rd instar. Head capsule 200 long, 125 wide, ratio 62%, antenna 1 70, 2–4 30, AR 2.3. Mandible length 32. Ligula length 32. Cephalic seta S5 relatively more anterior than in 4th instar.

Figures

Figure 1. Nilotanypus Kieffer. Adult. A–D. Head, anterior view, right side, ♂, A, C. ♀, B, D.; E–F. Thorax, E. dor- sal, F. lateral; G. Mid-dorsal sensory pit; H. Wing (male); I, J. Tibial apices, I. P1, J. P3; K. Male hypopygium; L. Gonostylus; M. Female genitalia left side only; N. Anterior vaginal cavity, detail. A–B, E–K, M–N. N. haplochelus sp. n.; C–D, L. N. ctenochelus sp.n. Abbreviations: fr–frontal setae, iv–inner vertical setae, ped–pedestal setae, ov– outer vertical setae, sc-scape setae. Fig. 1G after Roback, 1986.

Figure 2. Nilotanypus Kieffer. Pupa. A, B. Thoracic horn; C. Wing sheath; D–F. Abdomen, male); D. dorsal, E. ventral. Larva. F. Head capsule, left side ventral, right side dorsal; G. Dorsal head capsule; H. Antenna; I. Antennal apex, detail; J. Mandible; K. Ligula, paraligula; l. Maxilla; M. Submentum; N. Anterior parapod small comb claw; O. Posterior body; P. Posterior parapod comb claw. A, D–F, H–O. N. haplochelus sp. n.; B, C, G, P. N. ctenochelus sp. n. Abbreviations: S5 – S10 – cephalic setae, DP – dorsal pit, VP – ventral pit.