Crotonia queenslandiae, 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 : 35-37

Crotonia queenslandiae sp. nov.

( Figs. 13 , 18 m, 21)

Dimensions: holotype female length 1210, breadth 640. Paratype females length 1209, 1193; breadth 624, 630. Paratype males length 1043, 1035, 1059; breadth 521, 514, 577. Ratio of length of prodorsum to total body length: 0.33 (holotype).

Description of female. Prodorsum: ratio of length to breadth 1.0. Rostrum with squat naso, barely projecting beyond rostrum; lateral edges concave; rostral seta thin, short, spiniform, smooth ( Fig. 13 a). Lamellar seta 295, recurved, smooth. Lamellar apophyses 105, slightly inflexed, broadening basally, just under half as long as their mutual distance; extending anteriorly as far as apices of rostral setae. Interlamellar apophyses cylindrical (25 long, 10 broad); interlamellar seta 353, flagelliform, smooth; extending anteriorly as far as apex of curve of lamellar setae. Prodorsal ridges well-developed, curved medially, extending anteriorly almost half the distance between bases of interlamellar and lamellar apophyses. Diameter of each bothridium 47; anteriolateral auriculate ridge of bothridium a blunt, curved projection, longer than broad, bearing a series of invaginated ridges; hexagonal reticulations of operculum relatively small, not with point of origin near lateral margin; with dense parallel ridges and punctate borders ( Fig. 18 m). Inter-bothridial ridge and median field of muscle sigilla not apparent. Prodorsal microsculpture smooth, porose.

Notogaster: ratio of length of notogaster to breadth of notogastral shield 1.38; notogastral shield broadest at level of bases of setae e 2 ( Fig. 13 a); ratio of width of shield to entire notogastral width 0.95; margins of shield convex, sub-hexagonal. Dorsosejugal suture well-defined, with single discrete ridge. Lyrifissure ia 45 long. With 13 pairs of smooth notogastral setae (c 2 absent). Pre-notogastral shield separated from notogastral shield by narrow hyaline strip, and bearing long (364), flagelliform seta c 3 on long, cylindrical apophysis directed posteriolaterally and dorsally and well-developed, setiform, seta c 1 (224) emerging from squat tubercle on posterior margin. Notogastral shield uniformly porose except for narrow lateral region of small plaques between setae f 1 and f 2; notogastral margin in this region straight, sloping diagonally. Lateral hyaline strip (suprapleural scissure) narrow, bearing well-developed tubercles of curved, setiform setae cp and e 2 (both ca. 170). Seta d 2 thin, 34, setiform; mutual distance (162) the same as that between setae c 1. Setiform seta f 2 (123) on squat tubercle just projecting beyond margin of notogastral shield. Opisthosomal gland opening gla positioned anteriomedial of setae f 2. Caudal apophyses bi-lobed, broadly separated by transverse caudal margin; no caudal stalk present. Apophyses of h 2 straight, short (62), though longer than others, directed posteriolaterally, a third as long as their mutual distance, positioned at obtusely-angled junction between transverse and posteriolateral caudal margins. Apophyses of h 1 (28) emerging on posteriolateral caudal margin, separate from apophyses of h 2; apophyses of f 1 (22) projecting dorsolaterally, separated from, and anterior of, those of h 1. Apophysis of seta h 3 positioned ventral and medial of those of h 2. Caudal setae short, smooth, flagelliform apically; f 1 and h 1 reflexed, (95–115), h 2 straight, 132 spiniform, flagelliform apically, h 3 48.

Ven te r: epimeral microsculpture smooth, porose ( Fig. 13 b); epimeral setae short (11–17), smooth, spiniform, formula 3-1-3-3; 4a longer than others (33; Fig. 13 d); 3c on well-developed tubercle. With lcs broad, diagonal, curved, forming a broad obtuse angle (ca. 150°) with pcs. Anteriolateral margin of adanal plate with a narrow, deep indentation. Genital plates circular; posterior margin rounded. Perigenital region smooth, porose. Each genital plate 198 long, 110 broad, with eight short, spiniform setae; two pairs of aggenital setae, subequal in length to epimeral setae. Anal plate 55 broad, 281 long, with three short (22) spiniform setae on central region; three pairs of spiniform adanal setae, ad 2-3 shorter (22) and thinner than ad 1 (38). Distance between ad 2 and ad 3 half that between ad 1 and ad 2. Ventral margin of notogaster surrounding anal plates acutely V-shaped, apex projecting beyond caudal margin. Setae of p series flagelliform apically, p 1 and p 2 subequal in length (63–74), mutual distance between tubercles of p 1 about the same as width of tubercle.

Lateral view: Caudal margin perpendicular to notogastral shield as far as apophyses of seta p 1, then angled anterioventrally ( Fig. 13 c). Dorsal and ventral surfaces not parallel, distance between them perpendicular of seta e 2 ca. 505, narrowing anteriorly. Caudal apophyses positioned at level lower than that of notogastral shield. Apophysis of seta f 1 pointing anteriodorsally, h 1 posteriodorsally; those of h 2 slightly less than twice the length of h 1, horizontal, pointing posteriorly; those of h 3 positioned ventral of h 2, pointing posteriorly. Apophysis of seta p 1 on caudal region, slightly more than a third of the distance between ventral and dorsal surfaces; p 2 positioned at junction between caudal margin and ventral surface; distances between p series subequal. Pleuraspis with scattered tubercles in dorsal half.

Material examined. Holotype female, QM S26062 , malaise trap, rainforest, Mount Glorious, Queensland, 27°20'S 152°46'E, 570 m., coll. A. Hiller, 26.v.–10.viii.1983. Paratype female, canopy fogging, subtropical rainforest (complex notophyll vine forest), Wishing Tree Track, O’Reilly’s Rainforest Retreat, Green Mountains, Queensland, 28°14'03"S, 153°08'16"E, ca. 900 m., coll. R.L. Kitching, 1989–1991 (Lam H5 89-91, bulked sample). Paratype female and three paratype males, same data as previous sample but coll. March, 1991 (L-20-3). Holotype and paratypes from QM samples deposited in the Queensland Museum, Brisbane; paratypes from Lamington National Park deposited in the Australian National Insect Collection, CSIRO Ecosystem Sciences, Canberra.

Etymology. This species is named for the State of Queensland.

Remarks. Crotonia queenslandiae differs from all other Crotonia spp. by the following combination of characters: 1) the sub-hexagonal notogastral shield, and especially the angular shape of the posterior part of the shield; 2) the short caudal apophyses separated from one another and with those of h 3 medial of those of h 2; 3) the porose notogastral shield with a narrow region of small plaques between setae f 1 and f 2; 4) the large, dorsoposteriolaterally-directed apophyses of setae c3; 5) the apparent absence of an interbothridial ridge or centroprodorsal muscle sigilla; 6) ventral margin of notogaster surrounding anal plates acutely V-shaped, projecting beyond caudal margin; 7) setae 4a longer than others.

The arrangement of the short, separate, lateral caudal apophyses of Crotonia queenslandiae is similar to those members of the Lanceolata species-group, except they have apophyses of setae h 3 the longest, not h 2 ( Colloff, 2009b). Although Crotonia queenslandiae is a member of the Cophinaria species-group, it is not morphologically particularly similar to any other member of the group. It has some character states in common with C. yeatesi , a member of the Capistrata group, particularly its outline in lateral view with a convex dorsal surface, with dorsal and ventral surfaces not parallel and the distance between the narrowing anteriorly, the caudal apophyses below the level of the dorsal shield, the relative lengths and arrangement of the caudal apophyses and the perpendicular caudal margin. The long, flagelliform setae c 3 and c 1 on welldeveloped apophyses are shared with all Queensland members of the Cophinaria species group described herein. The angular shape of the posterior part of the notogastral shield is shared with C. seemani sp. nov. and, to a lesser extent, C. eungella as well as C. yeatesi .

The material from O’Reilly’s Rainforest Retreat, Lamington National Park was collected by pyrethrin knockdown of rainforest canopy (see Walter et al., 1998 for ecological details).

Figures

FIGURE 13. Crotonia queenslandiae sp. nov. holotype female a) dorsal; b) ventral; c) lateral; d) detail of seta 4 a.

FIGURE 18. Details of bothridia of a) Crotonia sterigma sp. nov.; b) Crotonia borbora Luxton, 1987; c) Crotonia brisbanensis sp. nov.; d) Crotonia maculata sp. nov.; e) Crotonia capistrata Luxton, 1987; f) Crotonia ardala Luxton, 1987; g) Crotonia monteithi sp. nov.; h) Crotonia daviesae sp. nov.; i) Crotonia weiri sp. nov.; j) Crotonia yeatesi sp. nov.; k) Crotonia cameroni sp. nov.; l) Crotonia eungella sp. nov. m) Crotonia queenslandiae sp. nov.; n) Crotonia seemani sp. nov.; o) Crotonia raveni sp. nov.