Novonothrus coronospinosus, Colloff, Matthew J., 2011

Colloff, Matthew J., 2011, A review of the oribatid mite family Nothridae in Australia, with new species of Novonothrus and Trichonothrus from rain forest and their Gondwanan biogeographical affinities (Acari: Oribatida), Zootaxa 3005, pp. 1-44 : 8-12

publication ID	https://doi.org/ 10.5281/zenodo.204042
DOI	https://doi.org/10.5281/zenodo.6194599
persistent identifier	https://treatment.plazi.org/id/210C87C8-E874-FFC3-89AF-5C3D603A5C17
treatment provided by	Plazi
scientific name	Novonothrus coronospinosus
status	sp. nov.

Treatment

Novonothrus coronospinosus View in CoL sp. nov.

(Figs. 3–5, 12f, 17b, 18b)

Dimensions. Holotype female length 1067 μm, breadth 624 μm. Paratype females (n = 5) mean length 1056 μm (range 1003–1081 μm), mean breadth 608 μm (range 585–648 μm); paratype males (n = 16) mean length 944 μm (range 924–969 μm), mean breadth 513 μm (range 493–555 μm).

Female. Prodorsum: Median light oval region 23 μm long 26 μm broad; Y-shaped ridge medial of lateral light oval regions (each 48 μm long, 40 μm broad). Rostral setae (ro) straight, smooth, spiniform, 43 μm long (Fig. 3a). Lamellar seta (le) 46 μm long, smooth, straight, spiniform, on squat tubercle positioned laterally. Margin of prodorsum with three short, spiniform lateral setae (l 1-3) on each side between setae ro and le, 37–46 μm long. Prodorsum slightly expanded laterally in region posterior of lamellar setae. Interlamellar seta (in) 70 μm long, barbed, covered with cerotegument. Bothridium with anterior ridge extending towards le, joined to medial ridge to form elongate, shallow, alveolate indentation. Bothridial rim rounded. Exobothridial seta ex 1 not visible from above. Bothridial seta (bs) flagelliform, smooth, 238 μm long, apex reflexed. Prodorsum alveolate.

Notogaster: Ratio of length to breadth 1.19. Notogaster broad, sub-oval (Fig. 3a). Notogastral cuticle with large irregular alveoli (5–10 μm diameter), almost adjacent ( Fig. 17 View FIGURE 17 b). Notogastral setae of c -h series, plus p 1-2, slightly curved, pointed, sparingly barbed apically (Fig. 3c), covered in cerotegument, c series shorter (28–41 μm) than others (50–72 μm); seta p 3 straight, smooth, spiniform, 36 μm long. Distance between setae c 1 1.4 × that between c 1 and c 2; distance between setae c 1 0.7 × that between d 1; distance between d 2 1.5 × that between d 1; distance between e 1 1.5 × that between f 1. Caudal margin rounded, without median and lateral crenellations. Faint longitudinal ridge on either side of notogaster extending from lateral of gla to point just posterior of c 3.

Subcapitulum: Mentum foveolate; gena with four setae: a and m 1-3, a longer than others (Fig. 3b); coxal spine (e) present. With two adoral setae ( Fig. 12 View FIGURE 12 f); or 1 bifurcate; or 2 curved, bacilliform.

Coxisternum: Epimeral plates I and II adjacent, epimeral plates III and IV separated along sternal line (Fig. 3b). Epimeral setal formula variable: most frequently 8-5-6-5 (8 of 11 paratypes), 8-6-6-5 (1 of 11) 8-4-6-6 (1 of 11) or 7-5-6-6 (1 of 11); 8-5-6-5 on holotype; frequently asymmetric (4 of 11 paratypes): range of variation: (7,8)-(4-6)- (6,7)-(5-7). Epimeral setae smooth, setiform, sub-equal in length (18–28 μm), except for longer seta 2b (48 μm).

Epimeral plates I and II with setae on anterior, medial and posterior parts; setae of plate III on medial part; those of plate IV on posterior part. Epimeral plate IV broadly triangular, with triangular posteriomedian flange adjacent to genital plate.

FIGURE 3. Novonothrus coronospinosus sp. nov., holotype female; a) dorsal; b) ventral; c) detail of seta h 1; d) lateral view.

Anogenital Region: Each genital plate 212 μm long, 98 μm broad, divided transversely, with nine smooth setiform setae; g 5 thicker, longer (58 μm) than others (21–29 μm): six setae in median file (three on anterior part of plate), three in lateral file (one on anterior plate; Fig. 3b). Pre-anal plate triangular, 148 μm broad. Each anal plate 286 μm long, 64 μm broad, with two smooth, spiniform setae, 37 μm long; one on anterior, one on posterior part of plate. Adanal setae subequal in length and shape to anal setae. Ventral margin of notogaster posterior or anal plates entire, rounded.

Lateral View: Anterior prodorsal margin blunt, curved vertically and slightly posteriorly; setae l 1-3 spaced equidistantly along lateral prodorsum (Fig. 3d). Lamellar seta projecting as far as base of rostral seta. Exobothridial seta ex 1 short (18 μm), spiniform, with cerotegument; ex 2 present as alveolus. Interbothridial region convex. Lyrifissure ia long (46 μm). Notogastral shield slightly convex, elongated, relatively flat between setae c 1 and f 1; ratio of notogastral height to length 0.59. Opening of opisthonotal gland positioned posteriolateral of seta f 2, prominent, slitlike, surrounded by circular ridge of cuticle.

Legs: Pre-tarsus monodactylous. Femur I 208 μm long; setae l ' strongly barbed, longer (88 μm) than others (38–53 μm); d, l "1 and l "2 sparingly barbed ( Fig. 18 View FIGURE 18 b).

Deutonymph. Length 515 μm, breadth 258 μm. Prodorsum: Length 221 μm. median light oval region 11 μm long 20 μm broad, with transverse ridge between rostral setae; lateral light oval regions 22 μm long, 14 μm broad ( Fig. 4 View FIGURE 4 a). Rostral seta (ro) straight, smooth, spiniform, 26 μm long, covered in cerotegument. Lamellar seta (le) 22 μm long, spiniform, smooth, covered in cerotegument, on squat, conical tubercle towards lateral margin of prodorsum. Lateral margin of prodorsum with one short (14 μm), spiniform seta (l 1) on each side level with seta le. Interlamellar seta (in) barbed, 38 μm long, covered in broad, flattened cerotegument, blunted apically. Bothridium with anterior ridge extending towards lamellar seta. Bothridial seta (bs) elongate, flagelliform, 227 μm long. Exobothridial seta (ex) spiniform, short (11 μm) protruding from posteriolateral margin of bothridium. Prodorsum reticulate; posterior region with tubercles interspersed with striate unsclerotised cuticle.

Gastronotic Region: Length 297 μm. Gastronotic region sub-rectangular ( Fig. 4 View FIGURE 4 a). Cuticle densely tuberculate laterally and ventrally, tubercles becoming more widely spaced dorsomedially. With pattern of bulbous projections and ridges extending from seta cp to f 1. Gastronotic setae 22–32 μm long, covered with broad, flat cerotegument, those of c -h series and p 1 barbed, p 2-3 smooth. Distance between bases of setae c 1, d 1, e 1 and f 1 sub-equal; distance between bases of setae d 2 markedly wider. Caudal margin incised between setae h 1 and h 2.

Subcapitulum: Mentum foveolate; Gena with setae a and m 1-2.

Coxisternum: Epimeral plates separated along sternal line by unsclerotised longitudinally striate cuticle ( Fig. 4 View FIGURE 4 b). Epimeral setal formula 4-3-3-2. Epimeral setae smooth, setiform, sub-equal in length (11–15 μm). epimeral plates I–III with setae on medial part, setae of plate IV near posterior margin. Epimeral plates IV lacking triangular posteriomedian flange adjacent to genital plate.

Anogenital Region: Each genital plate 49 μm long, 19 μm broad, entire ( Fig. 4 View FIGURE 4 b), with four smooth, setiform setae, 13–18 μm long. Genital plates surrounded by sparse tubercles interspersed with striate cuticle. Each anal plate 127 μm long, 22 μm broad, sparingly tuberculate. Adanal setae spiniform, smooth, 12–15 μm long.

Tritonymph. As for deutonymph, except as follows: length 595 μm, breadth 324 μm. Prodorsum: Lateral margin of prodorsum with two short (14 μm), spiniform setae (l 1-2) on each side just posterior of seta le ( Fig. 5 View FIGURE 5 a). Gastronotic Region: Length 467 μm). Cuticle densely tuberculate laterally and medially; setae h 2 and h 3 positioned on short indented ridge. Subcapitulum: Gena with setae a and m 1-2. Coxisternum: Epimeral setal formula 5-4-5-4 ( Fig. 5 View FIGURE 5 b); Setae on epimeral plates I–II on medial and posterior part, setae on plate III medial, those on plate IV near posterior margin. Anogenital Region: Each genital plate 51 μm long, 27 μm broad, not divided transversely ( Fig. 5 View FIGURE 5 b), with five smooth, setiform setae (12–16 μm long) in medial file and one anteriolaterally. Genital plates surrounded by striate cuticle. Each anal plate 157 μm long, 27 μm broad, smooth, with two pairs of spiniform smooth setae. Adanal setae spiniform, smooth, setae sub-equal in length (16–24 μm) to anal setae.

Material examined. Holotype female, seven paratype females, 19 paratype males, ANIC 770, 771, 772, litter under Nothofagus moorei, Wiangaree State Forest, New South Wales, 28°22'S 153°05'E, 1050 m., coll. T. Weir & A. Calder, 10–12.ii.1983. Non-type material: 35 nymphs, ANIC 770, 771, 772. Holotype and paratypes deposited in the Australian National Insect Collection, CSIRO Ecosystem Sciences, Canberra. Two paratypes in Roy A. Norton Collection, College of Environmental Science and Forestry, State University of New York, Syracuse.

Etymology. The specific name is from the Latin corona, ‘crown’, and spinosus, ‘thorny’, referring to the crown-like series of spiniform lateral prodorsal setae.

Remarks. Novonothrus coronospinosus differs from other members of the genus by the following combination of characters: 1) lateral margin of prodorsum with three short, spiniform setae (l 1-3) between setae ro and le; 2) interlamellar seta barbed; 3) notogastral setae barbed and covered with cerotegument except spiniform seta p 3; 4) setae on epimeral plates I and II positioned on anterior, medial and posterior part of plate; 5) the thick, elongated seta g 5; 6) the elongated lyrifissure ia; 7) with seta l ' of femur I markedly longer than the others.

Novonothrus coronospinosus View in CoL is morphologically most similar to N. flagellatus Hammer, 1966 View in CoL . Both species have three lateral prodorsal setae (l 1-3). Hammer (1966) described setae l 1-3 in the adult of N. flagellatus View in CoL (her Fig. 31a). As far as I am aware, the neotrichy of the lateral prodorsal region is unique to these two species within the Oribatida View in CoL . In N. coronospinosus View in CoL these setae appear in an ontogenetic sequence, with the posteriormost seta (l 1), present in the deutonymph, two in the tritonymph and all three present in the adult. It is on the basis of this character state, combined with the barbed anterior and posterior notogastral setae and their presence in the same samples, that the immatures are associated with the adults. Larvae and protonymphs of N. coronospinosus View in CoL were not recovered, so whether l 1 is present or absent in these stages is not known. Novonothrus coronospinosus View in CoL and N. flagellatus View in CoL also have all notogastral setae barbed except p 3; eight or nine setae on epimere I, as opposed to five or six in all other members of the genus and both species have a pattern of closely-spaced, irregular alveoli on the notogaster, quite different from that of other members of the genus. The species differ in that N. coronospinosus View in CoL is less elongated and more pear-shaped than N. flagellatus View in CoL , it has one pair of notogastral ridges rather than two, and its interlamellar setae are barbed rather than smooth.