Crotonia raveni, Colloff, Matthew J., 2010

Colloff, Matthew J., 2010, The Gondwanan relict oribatid genus Crotonia (Acari: Oribatida: Crotoniidae) from rainforests in Queensland and Northern New South Wales: new species show a mixed pattern of short-range and long-range endemism, Zootaxa 2649, pp. 1-51 : 40-45

publication ID	https://doi.org/ 10.5281/zenodo.198744
DOI	https://doi.org/10.5281/zenodo.6204658
persistent identifier	https://treatment.plazi.org/id/BB5587C4-A403-A610-FF7A-565F5D59FD75
treatment provided by	Plazi
scientific name	Crotonia raveni
status	sp. nov.

Treatment

Crotonia raveni View in CoL sp. nov.

( Figs. 15–21 View FIGURE 15 View FIGURE 16 View FIGURE 17 View FIGURE 18 View FIGURE 19 View FIGURE 20 View FIGURE 21 )

Dimensions: holotype female length 1662, breadth 692. Paratypes: females (n = 19): mean length 1637 (range 1541–1778); mean breadth 700 (range 577–780; males (n = 12): mean length 1411 (range 1319–1485); mean breadth 546 (range 435–616). Ratio of length of prodorsum to total body length: 0.31 (holotype).

Description of female. Prodorsum: ratio of length to breadth 1.03. Rostrum with squat naso, barely projecting beyond rostrum; lateral edges parallel; rostral seta 130, reflexed, spiniform, smooth ( Fig. 15 View FIGURE 15 a). Lamellar seta 420, recurved, smooth. Lamellar apophyses 197, straight, thin, slightly diverging apically, shorter than their mutual distance by a quarter; extending beyond apices of rostral setae. Interlamellar apophyses twice as long as broad; interlamellar seta 485, flagelliform, smooth; extending beyond apex of curve of lamellar setae. Prodorsal ridges absent. Diameter of bothridium 47; auriculate ridge of bothridium a blunt, sub-rectangular projection, with a series of sub-parallel ridges; hexagonal reticulations of operculum with concentric and parallel ridges and with point of origin near centre of bothridium, not near lateral margin ( Fig. 18 View FIGURE 18 o). Inter-bothridial ridge and median field of muscle sigilla absent. Prodorsal microsculpture smooth, porose.

Notogaster: ratio of length of notogaster to breadth of notogastral shield 1.47; dorsal notogastral shield broadest at bases of setae e 2 ( Fig. 15 View FIGURE 15 a); ratio of width of shield to entire notogastral width 0.8; lateral margins of notogastral shield oval, inflated. Dorsosejugal suture a discrete single ridge, rounded laterally. Region posterior of apophyses of setae c 3 concave, waisted, containing lyrifissure ia (46). With 14 pairs of smooth notogastral setae. Pre-notogastral shield separated from notogastral shield by narrow transverse hyaline strip, with blunt lateral projections, bearing long, well-developed, flagelliform setae c 1-3, subequal in length (715– 755) on long, cylindrical apophyses (50 long, 21 broad), those of setae c 1 on posterior margin of prenotogastral shield, those of c 2 located anteriomedially of them. Notogastral shield smooth, lateral margins convex, tapering to U-shape anterior of caudal apophyses, bordered laterally by narrow ridge extending to caudal region. Lateral hyaline strip (suprapleural scissure) very wide, bearing apophyses of setae cp, e 2 and f 2. Setae d 2 short (38), on alveoli ca 102 apart; same distance as between setae c 1. Setae cp (756) and e 2 (630) long, flagelliform. Opisthosomal gland opening gla positioned anteriomedial of setae f 2. Caudal apophyses bilobed, emerging direct from caudal margin. Apophysis of seta f 1 the longest of the caudal series (193), irregular, directed posteriolaterally, inflated basally; caudal margin between them convex. Apophysis of seta h 1 a quarter of the length of those of f 1, considerably thinner, emerging from medial region of apophyses of f 1. Apophyses of setae h 2 and h 3 located ventral of those of f 1 and h 1, separate, h 2 directed posteriolaterally, h 3 posteriomedially. Seta f 1 long, flagelliform, 672; h 1 105, h 2 117, h 3 457.

Ven te r: epimeral microsculpture smooth, porose ( Fig. 16 View FIGURE 16 a); epimeral setae smooth, spiniform, on welldeveloped cylindrical apophyses, formula 3-1-3-3; 25–35 long; 3c on well-developed tubercle. With lcs narrow, transverse, curved, forming slightly obtuse angle (ca. 105°) with pcs. Anteriolateral margin of adanal plate with narrow, deep indentation. Genital plates sub-circular. Perigenital and adanal region densely tuberculate. Each plate 284 long, 138 broad, with eight setiform setae, variable in length (52–95), on welldeveloped cylindrical apophyses; two pairs of aggenital setae, 34–43. Anal plate tuberculate, 77 broad 370 long, with three thick setae (30–44) on central region of plate; adanal setae spiniform; ad 2-3 32, ad 1 95. Margin of notogaster surrounding anal plates U-shaped. Setae of p series setiform; p 3 77, p 2 curved 108, p 1 flagelliform apically, 125; mutual distance between tubercles of p 1 about the same as length of tubercle. Tubercles of setae h 3 broad, sub-conical, on posteriolateral margins of bases of apophyses of setae h 2.

Lateral view: Caudal margin irregular, complex series of folds more-or-less perpendicular to notogastral shield ( Fig. 15 View FIGURE 15 c). Dorsal and ventral surfaces parallel, distance between them perpendicular of seta f 2 ca. 577; ventral surface curved in posterior part. Caudal apophyses positioned at level of notogastral shield. Apophysis of seta f 1 curved, horizontal, pointing posteriorly, h 1 pointing ventrally; those of h 2 and h 3 positioned ventral of apophysis of seta f 1, a quarter of the distance between dorsal and ventral surfaces. Apophysis of seta p 1 at junction between ventral surface and caudal margin; seta p 2 half the distance to p 3 as to p 1. Pleuraspis smooth.

Caudal view: Opisthosoma sub-hexagonal in cross section, with dorsolateral ridges ( Fig. 17 View FIGURE 17 a). Caudal apophyses separated into two groups: f 1 and h 1 dorsally, h 2 and h 3 ventrally; originating at points slightly below level of notogastral plate. Semi-circular ridge present ventral of p series, with short dorsal fissures lateral of setae p 3. Caudal region smooth.

Description of male. As for female except with the following characters. Prodorsum: rostral seta straight, spiniform, 61 long. Apophysis of lamellar seta 130 long ( Fig. 15 View FIGURE 15 b). Notogaster: ratio of length to breadth 1.58 ( Fig. 15 View FIGURE 15 b). Dorsosejugal suture with lateral blunt projections. Setae c 1-3 subequal in length (445–545) on long, cylindrical apophyses (40–60). Notogastral shield smooth, narrow, margins sub-parallel. Setae d 2, minute (25) emerging from alveoli ca 75 apart; same distance as between bases of setae c 1. Setae cp 675, e 2 545. Seta f 1 short (80), spiniform; h 1 recurved, setiform, 100; h 2 76. Ven te r: Perigenital and adanal region densely tuberculate; anal plate tuberculate anteriorly ( Fig. 16 View FIGURE 16 b). Anteriolateral margin of adanal plate without indentation. Each genital plate 197 long, 106 broad, with eight setiform setae (36–58) emerging from short tubercles. Margin of notogaster surrounding anal plates truncated; margin straight, horizontal. Setae p 2-3 setiform; p 1 flagelliform.

Material examined. Holotype female. Paratypes: ten females, six males, QM S26056 View Materials , litter, closed forest, Gold Creek Reservoir, Brookfield, Queensland, 27°30'S 152°55'E, 135 m., coll. V.T. Davies & R.J. Raven, 23.vi.1980. Paratypes: two females, two males, QM S26057 View Materials , litter, closed forest, Gold Creek Reservoir, Brookfield, Queensland, 27°30'S 152°55'E, coll. R.J. Raven, 28.i.1981. Paratypes: three females, two males, QM S26058 View Materials , litter, closed forest, Gold Creek Reservoir, Brookfield, Queensland, 27°30'S 152°55'E, coll. V.T. Davies & R.J. Raven, 15.x.1980. Paratypes: five females, two males, QM S26059 View Materials , litter, closed forest, Gold Creek Reservoir, Brookfield, Queensland, 27°30'S 152°55'E, coll. V.T. Davies & R.J. Raven, 15.x.1980. Paratype male, QM S26060 View Materials , litter, closed forest, Gold Creek Reservoir, Brookfield, Queensland, 27°30'S 152°55'E, coll. V.T. Davies & R.J. Raven, 1.x.1980. Holotype and paratypes deposited in the Queensland Museum, Brisbane.

Etymology. Crotonia raveni is named in honour of Dr Robert Raven (Queensland Museum), in recognition of his contribution to Australian arachnology.

Remarks. Crotonia raveni differs from all other Crotonia spp. by the following combination of characters: 1) the longest caudal apophysis is that of seta f 1, not h 2; 2) all lateral notogastral setae are greatly elongated and flagelliform; 3) the full complement of setae in the c series; 4) the apophyses of setae c 1-2 are very long and those of c 1 are positioned posterior to those of c 2; 5) the caudal apophyses are separated into two groups: f 1 and h 1 positioned dorsally and h 2 and h 3 ventrally; 6) the broad strip of smooth, porous cuticle lateral of suprapleural scissure bearing lyrifissures im and ip and the apophyses of setae e 2 and f 2; 7) well-developed pre-notogastral shield with blunt lateral projections; 8) the epimeral and genital setae are on well-developed cylindrical apophyses; 9) the anal plates are tuberculate.

The association of the male and the female of C. raveni is based on the relative lengths and arrangement of the notogastral setae and the morphology of the caudal apophyses. The female has long setae f 1 whereas they are short in the male.

Crotonia raveni has no close morphological affiliation with any other members of the genus, primarily because the arrangement of the caudal apophyses in two separate groups is unique.