Crotonia momitoi, Colloff, Matthew J. & Perdomo, Giselle, 2009

Colloff, Matthew J. & Perdomo, Giselle, 2009, New species of Crotonia (Acari: Oribatida: Camisiidae) from Nothofagus and Eucalyptus forests in Victoria, Australia, with a redescription of the fossil species Crotonia ramus (Womersley, 1957), Zootaxa 2217, pp. 1-36 : 10-16

Crotonia momitoi sp. nov.

( Figs. 4–7 , 15 , 17–19 )

Dimensions. Holotype female length 1056, breadth 538; paratype females (n = 5): mean length 1069 (range 1010–1105); mean breadth 502 (461–550); paratype male length 947, breadth 474. Mean ratio of length of prodorsum to total length: 0.31 (both sexes). Deutonymph length 485, breadth 202; Tritonymph length 751, breadth 300. Ratio of length of prodorsum to total length: deutonymph 0.4; tritonymph 0.39.

Female. Prodorsum: rostrum well-developed, with very prominent naso, lateral edges incurved; rostral setae (ro) 45, curved, smooth ( Fig. 4 a). Lamellar setae (le) 360, recurved, smooth, flagelliform. Lamellar apophyses 105, half as long as their mutual distance; extending anteriorly almost as far as apices of rostral setae. Interlamellar apophyses three times as long as broad; interlamellar setae (in) slender, 360, flagelliform, smooth; extending anteriorly as far as arc of lamellar setae. Prodorsal ridges extending half the distance between interlamellar and lamellar apophyses. Bothridia with elongated cuticular ridges extending anteriolaterally. With well-developed posterior inter-bothridial ridge in the form of two flat curves; cuticle posterior of ridge smooth. Median field of muscle sigilla present. Prodorsum porose.

Subcapitulum: mentum with dense porose regions laterally, smooth medially; spiniform setae m 20, with phylliform cerotegument. With only two setae on gena: a 18; m 6. Oral setae or 1 slender, bifurcate, sparsely barbed bilaterally; or 2 and or 3 spiniform, curved, subequal, 21 ( Fig. 15 c). Palp setal (and solenidial) formula: 1-1-2-9(1).

Notogaster: ratio of length to breadth 1.45; broadest between bases of setae e 2 and f 1 ( Fig. 4 a). Dorsosejugal suture discrete, simple. With 13 pairs of notogastral setae; those of f and h series barbed, others smooth. Pre-notogastral shield bearing long (160), flagelliform setae c 1 and separated from notogastral shield by transverse hyaline strip. Apophyses of setae c 3 prominent, 30, at least twice as long as broad; setae c 3 flagelliform, 330, extending as far as bases of lamellar apophyses. Notogastral shield discrete, porose; bordered laterally by two narrow strips of small tubercles extending posteriorly almost as far as setae f 1. Caudal region with sparse tubercles, extending onto lateral notogastral plates. Lateral hyaline strip (suprapleural scissure) well developed, bearing tubercles of setae cp and e 2 Tubercles of setae f 2 short (22) but projecting beyond lateral margin. Flagelliform, proximally-barbed setae f 2 180; cp 150; e 2 120. Setae d 2 very long, 130, flagelliform. Opisthosomal gland opening gla positioned at level slightly anterior of f 2. Flagelliform setae f 1 125, their apophyses projecting posteriolaterally, slightly separated from, and parallel with, those of h 1. Setae h 2 75, spinose, barbed; their apophyses long, 120, parallel for most of their length, diverging apically; caudal margin between them transverse, apophyses of setae h 3 positioned ventral of h 1 when viewed dorsally. Apophyses of setae f 1 and h 1 25–30, cylindrical, subequal; those of h 3 15, squat.

Ven t er: epimeres porose ( Fig. 5 a); epimeral setae smooth, spiniform, formula 3-1-3-3; setae 4a longer than others, 3c on well-developed tubercle. Genital plates sub-circular. Each plate 174 long, 110 broad with eight spiniform setae; two pairs of aggenital setae, subequal in length to genital setae. Anal plate 20 broad, 220 long with three spiniform setae on posterior half of anal plate; three pairs of spiniform adanal setae. Ventral margin of notogaster surrounding anal plates U-shaped. Setae of p series smooth, flagelliform, p 3 65, p 2 72, p 1 195, on short tubercles; setae p 1 separated by distance twice the width of their tubercles ( Fig. 5 a).

Male. Prodorsum and Notogaster: As for female, except rostrum less prominent and rostral setae (ro) straight ( Fig. 4 b); setae c 1 and d 2 shorter, cp slightly longer and e 2, f 1 and h 1 markedly longer; p 1 shorter relative to p 2 and p 3 ( Fig. 5 b); anal, genital aggenital and epimeral setae (except 3c) slender, fine.

Lateral view: Caudal margin perpendicular to notogastral shield ( Fig. 17 a); distance between dorsal and ventral surface ca. 330. Apophyses of setae f 1, h 1 and h 2 directed dorsolaterally; those of h 3 positioned ventrally at point between apophyses of f 1 and h 1, directed ventrolaterally. Apophyses of setae p 1 positioned most dorsally on caudal region, then p 2, then p 3. Distance between apophyses of p 1 and h 3 190.

Deutonymph. Prodorsum: rostrum with prominent naso, lateral edges incurved; rostral setae (ro) 42 curved, smooth ( Fig. 6 a). Lamellar setae (le) 185 recurved, smooth. Lamellar apophyses 45, a third as long as their mutual distance; extending anteriorly as far as apices of rostral setae. Interlamellar setae (in) 205, flagelliform, smooth; extending anteriorly almost as far as arc of lamellar setae. Prodorsal ridges extending half the distance between interlamellar and lamellar apophyses. Bothridia with elongated cuticular ridges extending anteriolaterally. With well-developed posterior inter-bothridial ridge in the form of straight, flat Vshape. Median field of muscle sigilla present. Prodorsum porose; region posterior of interbothridial ridge with striate unsclerotised cuticle.

Notogaster: ratio of length to breadth 1.44; broadest at base of apophyses of setae c 3 ( Fig. 6 a). Dorsosejugal suture marked by series of diagonal striae. With 13 pairs of notogastral setae, all smooth. Each setae c 1, 52, situated at lateral end of oval porose sclerite. Setae d 2 37, not on sclerite. Apophyses of lateral setae prominent tubular extensions of ovoid porose sclerites. Apophyses of setae c 3 longest, 37, of lateral series. Lateral setae flagelliform, c 3 155, cp 215, e 2 170, f 2 110, f 1 175, h 1 205. Setae h 2 stout, incurved, 115, with flattened point or notched apically; apophyses elongated, tubular, 135, attenuated apically, divergent. Notogaster with series of longitudinal lines of tubercles interspersed by striate unsclerotised cuticle.

Ven t er: epimeres porose ( Fig. 6 b), with median unsclerotised longitudinally striate integument, diverging laterally and becoming transverse posterior of genital plates. Epimeral setae smooth, spiniform, some with bacilliform cerotegument, formula 3-1-3-3; setae 3c longer than others, on well-developed tubercle. Genital plates elongate, ovoid; each plate 62 long 19 broad with four spiniform setae; one pair of aggenital setae, subequal in length to genital setae. Anal plate 124 long, 22 broad; three pairs of spiniform adanal setae; ad 1 longer than others, on prominent tubercle. Setae of p series on sclerotised apophyses; p 2, 46, and p 3, 87 setiform, p 1 flagelliform, 120, their apophyses adjacent. Posterior region of venter tuberculate.

Tritonymph: Prodorsum: rostrum as for protonymph ( Fig. 7 a). Lamellar setae (le) 280 recurved, smooth. Lamellar apophyses 68, half as long as their mutual distance; extending anteriorly almost as far as apices of rostral setae (ro). Interlamellar setae (in) 285, flagelliform, smooth; extending anteriorly almost as far as arc of lamellar setae. Prodorsal ridges extending two-thirds of the distance between interlamellar and lamellar apophyses. Bothridia with narrow, elongated cuticular ridges extending anteriolaterally. With well-developed posterior inter-bothridial ridge in the form of straight, flat U-shape. Median field of muscle sigilla present. Prodorsum porose; region posterior of interbothridial ridge with striate unsclerotised cuticle.

Notogaster: ratio of length to breadth 1.58; broadest at base of apophyses of setae e 2 ( Fig. 7 a). Dorsosejugal suture marked by conjunction of diagonal striae and tuberculate cuticle. With 13 pairs of notogastral setae, all smooth. Each setae c 1, 84, situated at lateral end of oval porose sclerite. Setae d 2 103, on tubercles. Apophyses of lateral setae prominent tubular extensions of ovoid porose sclerites. Apophyses of setae c 3 the longest, 73, of lateral series. Lateral setae flagelliform, c 3 258, cp 345, e 2 280, f 2 188, f 1 352, h 1 375. Setae h 2 stout, curved, 202, with flattened point or notched apically; apophyses greatly elongated, tubular, 220, attenuated apically, divergent. Notogaster with series of longitudinal lines of tubercles interspersed by striate unsclerotised cuticle.

Ven t er: epimeres porose ( Fig. 7 b), with median unsclerotised longitudinally striate integument, diverging laterally and becoming transverse posterior of genital plates. Epimeral setae smooth, spiniform, some with bacilliform cerotegument, formula 3-1-3-3; setae 3c markedly longer than others, on well-developed tubercle. Genital plates elongate, ovoid; each plate 80 long 24 broad with six spiniform setae; one pair of aggenital setae, subequal in length to genital setae. Anal plate 164 long, 35 broad; three pairs of spiniform subequal adanal setae. Flagelliform setae of p series on sclerotised apophyses; setae p 2 80, p 3 120 setiform, p 1 160, their apophyses adjacent. Posterior region of venter closely tuberculate.

Material Examined and Locality Data. Holotype female, one paratype female and one paratype male, from moss, Dicranoloma billardierei, The Beeches, Lady Talbot Drive , near. Warburton, Yarra Ranges National Park, Victoria, 37°29'13.53"S 145°49'59"E, 800 m, coll. G. Perdomo, ix.2008. One paratype female, sieved litter, Eucalyptus forest, near summit of Mount Donna Buang, ca. 6 km NNW of Warburton, 37°42'25"S 145°40'43"E, 1240 m, coll. D. Black, 27.v.1990. One paratype male, litter, wet sclerophyll forest, Mt. Donna Buang, Yarra Ranges National Park, Victoria, 37°42’S, 145°41’E, 1050 m, coll. R.W. Taylor & R.J. Bartell, 5.xi.1970 ( ANIC Berlesate no. 299). One paratype female, sieved litter and rotting wood, open Eucalyptus forest, ca. 860 m, on Acheron Way, 2 km south of junction with Marysville Rd., ca. 18 km NE of Healesville, Victoria, 37°33'38"S 145°40'49"E, 440 m, coll. D. Black, 4.iii.1990. Four paratype females, two paratype males, moss and litter, rainforest with Nothofagus cunninghami, Cumberland Creek Valley , near Cumberland Memorial Picnic Area [Cumberland Scenic Reserve], Yarra Ranges National Park, Victoria. 37°34’S 145°52’E, 920 m, coll. R.W. Taylor & R.J. Bartell, 4.xi.1970 ( ANIC Berlesate no.297). Three paratype males, two paratype females, litter, Snowgum forest ( Eucalyptus pauciflora ), Lake Mountain, Yarra Ranges National Park, Victoria. 37°30’S 145°53’E, 1200 m, coll. R.W. Taylor & R.J. Bartell, 4.xi.1970 ( ANIC Berlesate no.296). Two paratype females, sieved litter, Eucalyptus forest, 4 km W. of Balook near west entrance to Tarra-Bulga National Park, Victoria, 38°26'20.59"S 146°31'17.29"E, 590 m, coll. D. Black, 26.i.1990. Ten paratype females, five paratype males, moss on trunk of Sassafras ( Atherosperma moschatum ), cool temperate rainforest, 1077 m, Errinundra Saddle, Errinundra National Park, Victoria, 37°19’18”S 148°51’11”E, 1030 m, coll. M.J. Colloff, 30.v.2009 ( ANIC Berlesate sample no. 4016).

Other Material: one protonymph, one tritonymph, same data as ANIC Berlesate no.297; ten nymphs, same data as ANIC Berlesate sample no. 4016.

Holotype and paratypes from The Beeches and Mt. Donna Buang deposited in Department of Entomology, Museum Victoria, Melbourne. Remaining paratypes in Australian National Insect Collection, CSIRO Entomology, Canberra.

Etymology. This species is named in memory of the second author’s grandfather, Pedro Perdomo, known affectionately as ‘Momito’.

Remarks. The association of the male and the female of Crotonia momitoi sp. nov. is based on the following shared characters: 1) the morphology of the caudal apophyseal cluster and its barbed, elongate flagelliform setae f 1, h 1 and h 3; 2) the long, smooth flagelliform setae p 1; 3) the short anal plates, removed some distance from the caudal margin; 4) the concordant dimensions of some of the non-caudal notogastral setae, particularly c 1, c 3, d 2 and f 2; 5) the prominent tubercles of setae c 3 and 6) the position and dimensions of the apophyses of setae h 3. As well as being smaller, the male differs from the female in having relatively longer setae cp and e 2. The association of immatures with adults is based upon samples from Errinundra National Park, which contains only this species and C. blacki sp. nov. Like the adults, the immatures of C. momitoi sp. nov. have longer setae c 1, d 2, p 1, setae h 2 and their apophyses, as well as narrow, elongate, anteriolateral bothridial auriculae, compared with those of C. blacki sp. nov.

Crotonia momitoi sp. nov. is a member of the Cophinaria species group ( Wallwork, 1977; Luxton, 1982; Colloff, 2009b). It differs from all other species in the genus as follows: 1) female with setae c 1 very long: longer than cp and e 2; subequal in length to f 1; 2) setae d 2 very long, only slightly shorter than c 1 in both sexes, as long as cp and e 2 in female; 3) setae f 1, f 2, h 1 long, flagelliform, lightly barbed proximally; 4) large, broad curved rostral setae; 5) setae p 1 unusually long, flagelliform, positioned some distance from caudal margin; 6) anal plates short, attenuated; 7) bothridia with elongated cuticular ridges extending anteriolaterally. Other species have a short ridge or prominence in the region anteriolateral of each bothridium, but the only other species with a structure of similar elongated shape and dimensions is C. jethurmerae Lee, 1985 .

Crotonia momitoi sp. nov. is morphologically most similar to C. blacki sp. nov. (cf. below) and Crotonia pyemaireneri Colloff 2009 from Tasmania, especially in the morphology and microsculpture of the notogastral shield and the caudal setae, as well as the relative dimensions of the c series and the prominent apophyses of setae c 3. It differs from these in having flagelliform, proximally-barbed setae f 2, much longer setae d 2 and in the shape of the caudal apophyseal cluster.

Figures

FIGURE 4. Crotonia momitoi sp. nov. Dorsal a) holotype female; b) paratype male

FIGURE 5. Crotonia momitoi sp. nov. ventral a) holotype female; b) paratype male

FIGURE 7. Crotonia momitoi sp. nov. tritonymph a) dorsal; b) ventral

FIGURE 15. Crotonia gadubanudi sp. nov. paratype female a) subcapitulum b) Oral setae (or). Oral setae of c) C. momitoi sp. nov. paratype female; d) C. blacki sp. nov. paratype female; e) C. alpina sp. nov.; f) C. cornuta sp. nov.; g) C. victoriae sp. nov. AS = adoral sclerite; G = gena; H = mentum; RU = rutellum.

FIGURE 17. Posteriolateral views of a) Crotonia momitoi sp. nov., male paratype; b) Crotonia blacki sp. nov. female paratype; c) Crotonia gadubanudi sp. nov.; d) Crotonia alpina sp. nov.; e) Crotonia cornuta sp. nov.; f) Crotonia victoriae sp. nov.

FIGURE 18. Details of bothridia of a) Crotonia momitoi sp. nov.; b) Crotonia blacki sp. nov.; c) Crotonia gadubanudi sp. nov.; d) Crotonia alpina sp. nov.; e) Crotonia cornuta sp. nov.; f) Crotonia victoriae sp. nov.

FIGURE 19. Distribution map of Crotonia spp. in Victoria. Stippled area is the distribution of the broad vegetation group categorised as ‘ wet or damp forests’ (Department of Sustainability and Environment, 2005). NP = National Park; SF = State Forest. Black circles are towns and cities, provided for spatial reference. Inset: 30 - year means of annual rainfall (source: Australian Bureau of Meteorology, www. bom. gov. au).