Cricotopus conicornis Drayson & Cranston

Drayson, Nick, Cranston, Peter S. & Krosch, Matt N., 2015, Taxonomic review of the chironomid genus Cricotopus v. d. Wulp (Diptera: Chironomidae) from Australia: keys to males, females, pupae and larvae, description of ten new species and comments on Paratrichocladius Santos Abreu, Zootaxa 3919 (1), pp. 1-40 : 11-13

publication ID	https://doi.org/ 10.11646/zootaxa.3919.1.1
publication LSID	lsid:zoobank.org:pub:218630EE-6BF7-4E35-A8F6-9E8260D60FA0
DOI	https://doi.org/10.5281/zenodo.6122638
persistent identifier	https://treatment.plazi.org/id/6FB4E9B1-401D-49BB-A5E5-6FFC003CF76A
taxon LSID	lsid:zoobank.org:act:6FB4E9B1-401D-49BB-A5E5-6FFC003CF76A
treatment provided by	Plazi
scientific name	Cricotopus conicornis Drayson & Cranston
status	sp. nov.

Treatment

Cricotopus conicornis Drayson & Cranston View in CoL sp. n.

( Figs. 1 View FIGURE 1 E, 2E, 4E, 6D, 7F, 8E, 11A)

urn:lsid:zoobank.org: act :6FB4E9B1-401D-49BB-A5E5-6FFC003CF76A

Cricotopus View in CoL ‘sp. C’ Drayson, 1992: 95

Cricotopus View in CoL “ conicornis ” sp. nov. Drayson & Cranston, in Cranston, 1996: 86 [Invalid; author states ‘not formal publication for nomenclatural purposes’]

Type material. Holotype: Le/Pe/♂, AUSTRALIA: ACT , Pierce's Ck. at Cotter, 35°20'S 148°56'E, 23.ix.1991 (Drayson)( ANIC).

Paratypes: Qld: Pe, Brisbane, Bundaroo Ck., 35°42'S 152°36'E, 27.ix.1989 (Cranston). NSW: 4 Pe, Warrumbungles, Shawn's Ck., Timor Rock, 31°16'S 149°09'E, 15.ix.1989 (Cranston); Le/P, 3 Pe, Rutherford Ck., Brown Mt., 36°36'S 149°47'E, 16.x.1990 (Cranston). ACT: Pe /♂, 2 Pe/♀, 2 Le/Pe/♀, 6 Pe, Le/Pe, as Holotype; 4 Pe, Corin Rd, Gibraltar Falls, 35°28'S 148°55'E, 25.viii.1989 (Cranston); same except Pe/♀, 4.xii.1991 (Drayson). Vic: P♂, P♀, Pe, Mitta Mitta, 10.x.1982 (Brittain); Pe, Big R., Omeo Highway, 36°54'S 147°27'E, 26.i.1989 (Cranston); L/P, U. Tambo R., CC10, 23.iii.1990, 36°58''S 147°54''E (Cranston); Le/P♂, Steavenson R., 37°28'S 145°45'E, 5.v.1993, (Schrieber); same except Le/P♀, 1.v.1993; 2Le/P♂, same except 7.iv.1993 (Downes et al); same except L/P, 20.iii.1992.

Other material examined. Qld: 2Pe, nr Mareeba, Davies Ck, 17°01'S 145°35'E, 27–28.viii. 1997 (Cranston); same except L(P), 2Pe, 11–12.iv.1997; same except 3Pe, 19–20.vi.1997;

5Pe, Kauri Ck., 17°06'S 145°35'E, 11.vi.1997 (McKie); Pe, Bartle Frere, Junction Ck. 17°16'S 146°55'E, 12–13.vi.1997 (Cranston), same except Pe, 27–28.viii.1997; Pe, P♀, Palmerston NP, Henrietta Ck, 17°36'S 145°45'E, 17.iv.1999 (Cranston); 7Pe, 17°47'S 145°41'E, 2–3.ix.1997 (McKie); 17Pe, Python Ck., 17°46'S 145°35'E,. 2–3.xi.1997 (McKie); 18Pe, Yuccabine Ck., 18°11'S 145°46'E, 9–10.vi.1997 (McKie); Qld: L, Mt Elliot NP, Alligator Ck., 23.iii.1998 (Cranston); L, Brisbane, Bundaroo Ck., 35°42'S 152°36'E, 27.ix.1989 (Cranston). NSW: 3L, Clyde Mt., Sugarloaf Ck., 35°33'S 149°58'E, 10.i.1988 (Cranston); 5Pe, Kosciuszko NP, Blue Lake, 36°24'S 148°18'S, 1875 m asl., 3.ii.1998 (Cranston); Pe, Kosciuszko NP, Charlotte’s Pass, Snowy R., 36°25'S 148°19'E, 1.xii.2010 (Cranston).

Molecular material. L, P♂, Qld, Dimbula, Kauri Ck., 17°06'S 145°35'E, 30.viii.2012 (Cranston) (Mv- FNQ12.2.5, 12.2.6); Pe, Mt. Lewis, Churchill Ck., 16°34'S 145°20'E, 30.viii.2012 (Cranston) (Mv-FNQCh3); 3L, 3P♂, Tas: Devil’s Gulch Res., unnamed Ck., State Forest Rd, 41°38'S 146°17'E, 25.xi. 2013, 838 m asl (Krosch) (Mv-Tas13.1.P1-3, TAS13.1.1, 1.4, 1.11); 2L, Mt Field NP, Russell Falls Ck., 42°40'S 146°42'E, 3.xii.2013 (Krosch) (Mv-TAS 13.9.13, 9.21); L, Mt Field NP, Tyenna R., 42°41'S 146°43'E, 3.xii. 2013, 165 m asl (Krosch) (Mv-TAS 13.10.15).

Description. MALE ( Fig. 1 View FIGURE 1 E) (n = 4). 3.9–4.3 mm.

Head. Ant 1080–1128 µm; length Fl 1–12, 425–480 µm, Fl 13, 560–648 µm; A.R. 1.25–1.35. Palp. 364–456 µm. 2–3 Fr, 4 Po. Clyp moderately setose.

Thorax. Sct pale brown, almost hyaline, with mid-brown border. Other sclerites very pale brown with variably distinctive brown postnotum and vittae on scutum. Laps 3–6, Ac 17–19, Dc 11–15, Pa 4–5, Scts 12–14.

Wing. 2.6–2.8 mm. Sq, 9–10, R, 7–8.

Legs. All mid-brown; femora darker, tibia and tarsomeres slightly paler.

Abdomen. All tergites brown.

Hypopygium ( Fig. 2 View FIGURE 2 E). Gcx 220–230 µm, iv rounded, with or without posterior notch. Gst 86–94 µm, about 2/ 5 (0.39–0.41) Gcx, with crista dorsalis strongly developed.

FEMALE (n=4). 2.9–4.1 mm.

Head. Ant 321–370 µm. Palp 352–480 µm. Setation as male.

Thorax. Colour as male. Laps 3–6, Ac 19–23, Dc 10–16, Pa 3–4, Scts 12–13.

Wing (n=3). 1.8–2.7 mm; width 0.6–0.8 mm. Sq, 3–10, R + R 1 12–22, R4+ 5 10–14.

Legs and Abdomen. Colour as male.

Genitalia. Spermathecae comprising mid-brown, reniform, capsules with wide "neck" and straight or recurved ducts ( Fig. 4 View FIGURE 4 E).

PUPA. 3.3–4.7mm, pale to mid-brown, with clear reticulate pattern on abdomen.

Cephalothorax. Moderately rugose dorsally. Th 140–216 µm, width 50–68 µm; clearly pigmented mid-brown, tear-shaped and covered with pointed scales, especially distally ( Fig. 6 View FIGURE 6 D, 7F). Fs 90–150 µm conspicuous, on prefrons.

Abdomen ( Fig. 8 View FIGURE 8 E). PSB on II and III; reduced on III. Hook row on TII never>0.5 of segment (0.34–0.46). Anterolateral spinule fields on TII. Ls on VIII short (32–80 µm), Ls3 usually <1/10 width of segment (0.08–0.16). Ms 120–180 µm, less than 1/15 length of abdomen (0.047–0.063). Well developed spinules on SII and III.

4TH INSTAR LARVA ( Fig. 11 View FIGURE 11 A). (n = 4). 4.6–4.8 mm. H.l. 430–480 µm, very pale to mid-brown with darker posterior margin; abdomen hyaline; procercus hyaline.

Head. Ant 72–78 µm; Fl 1, 44–46 µm; Fl 2–5, 28–32 µm; A.R. 1.43–1.57. Md 136–148 µm, with smooth inner margin and modestly crenulate outer margin, mid-brown with distal 1/3 dark brown. Mentum 100 µm, pale brown posteriorly, mid-brown anteriorly: 6 pairs laterals, 1st laterals large, 2nd slightly reduced.

Abdomen. Pc 14–20 µm wide, A.s. 530–560 µm.

Etymology. The epithet conicornis derives from recognition of the cone-shaped (coni-) thoracic horn (- cornis) of the pupa. This remains a discriminatory feature.

Remarks. Adult males of C. conicornis can be distinguished by the combination of uniformly dark legs and abdomen and posteriorly projecting inferior volsella. Females also have uniformly dark legs and abdomen, and elongated spermathecal capsules. Pupae can be recognised by the large, apically scaly, yellow-brown thoracic horn and reticulate pattern on abdomen. Larvae can be recognised by the first lateral mental teeth being level with the median tooth, and the relatively short apical mandibular tooth relative to the large first inner tooth.

This species is similar in colour pattern to that described by Hergstrom (1974) for C. phaeosomatus. However C. conicornis differs in having the adult male AR much less than the 1.8 of Hergstrom (confirmed on Hergstrom's proposed holotype as 1.9).

The distribution of C. conicornis encompasses the tropical and subtropical parts of the continent, but includes some sites in alpine south-east Australia and Tasmania . The species preference seems for clean creeks and moderately healthy rivers.