Crotonia aculeata, Colloff, Matthew J., 2009

Colloff, Matthew J., 2009, Species-group concepts and biogeography of the genus Crotonia (Acari: Oribatida: Crotoniidae), with new species from South and Central America, Zootaxa 2081, pp. 1-30 : 16-17

Crotonia aculeata sp. nov.

(Fig. 9)

Dimensions: holotype female and paratype female: length 1229, 1139; breadth 620, 627; ratio of length of prodorsum to total length: 0.3.

Female. Prodorsum: rostrum well-developed but not prominent, 16 long, 55 broad; rostral setae 25 long, straight, smooth (Fig. 9a). Lamellar setae recurved, ca. 395, smooth. Lamellar apophyses very well developed, 165 long, 40 broad, incurved, laminate, extending well beyond apices of rostral setae. Interlamellar apophyses twice as long as broad; interlamellar setae flagelliform, smooth, 440 long, extending as far as apex of arch of lamellar setae. Prodorsal ridges straight, angled obtusely halfway, extending about two thirds of the distance between interlamellar and lamellar apophyses; alveolate microsculpture lateral of ridges, otherwise porose. Sensillus globular, enclosed in bothridium, with veined microsculptural covering. Posterior interbothridial ridge angled, medial ridge straight; with well-developed alveolar field on posterior prodorsum.

Notogaster: 830 long; ratio of length to breadth 1.3; broadest at level of seta e 2 (Fig. 9a). With 13 pairs of notogastral setae; all smooth. Dorsosejugal suture complex, with well-defined waisted lateral margins and rectangular pre-notogastral shield, with alveolate microsculpture. Setae c 1 minute, 15 long, emerging from alveoli on small oval plates; setae c 3 405 long, extending anteriorly as far as bases of lamellar apophyses. With prominent apophyses of setae c 3 well-developed, twice as long as broad, positioned on posterior to waisted humeral region on transverse hyaline strip representing the anterior margin of notogastral shield. Lateral hyaline strip extending posteriorly as far as apophyses of setae f 2 and bearing tubercles of setiform, subequal setae cp and e 2. Notogastral shield alveolate-reticulate (Fig. 9d) bordered laterally by two broad strips of porose cuticle. Setae d 2 minute,15 long, on alveoli positioned relatively anteriorly on notogastral shield, posteriomedial of cp. Setae f 2 stout, straight, spiniform, 95 long, on prominent apophyses, 65 long, projecting posteriolaterally well beyond border of notogastral shield. With gla positioned immediately lateral of f 2. Setae f 1, h 1 and h 2 curved, smooth, slightly curved, subequal, 130; apophyses of f 1 and h 1 55 long, adjacent, parallel, projecting posteriolaterally. With tritonymphal exuvium attached to caudal region (Fig. 9e). Apophyses of h 2 curved, elongated, 210, directed posteriolaterally, 160 apart at base, 295 apically; caudal margin between them slightly concave. Setae h 3 positioned immediately ventral of, and in line with, apophyses of h 2; straight, spiniform, smooth; apophyses 65 long.

Ve n te r: epimeral microsculpture porose with broad foveolae (Fig. 9b); epimeral setae smooth, spiniform, minute, formula 3-1-3-3; seta 3c subequal to 3a and 3b, positioned on medial field or posterior border of epimere. Ventral margin of notogaster surrounding anal plates V-shaped; genital plates sub-circular; each plate 190 long, 120 broad with nine spiniform setae about same length and shape as epimeral setae. Aggenital setae subequal to epimeral setae. Anal plate 55 broad, 325 long; adanal setae ad 1 slightly longer than others; p 1 curved, subequal to p 3, on closely-adjacent tubercles (Fig. 9c).

Material examined and locality data. Type material: holotype and one paratype, ex. Berlese funnel extraction of roadside leaf litter in cloud forest, San Lorenzo, Guatemala, coll. J. M. Campbell, 6th July1986, ex. Canadian National Collection of Insects, Arachnids and Nematodes, Ottawa, Ontario, where the types are deposited.

Etymology. The specific name is derived from the Greek, akis, a point, needle or spine, and refers to the prominent, spiny setae f 2 and their apophyses.

Remarks. Crotonia aculeata can be differentiated from other species of the genus by the following combination of characters: 1) the very broad notogastral shield; 2) the massive lamellar apophyses; 3) the prominent apophyses of setae f 2; 4) the morphology of the prodorsal and interbothridial ridges and associated cuticular microsculpture and 5) the very long, well-developed setae c 3 and their apophyses, juxtaposed with the minute setae c 1.

This species has typical characteristics of the Cophinaria species-group. It is most similar to C. marlenae in the large broad notogastral shield prominent apophyses of setae f 2, strongly reduced setae d 2, and 9 pairs of genital setae, but C. marlenae has short setae c 1 and c 3, a porose centrodorsal shield and the epimeral setal formula 3-1-3-2 rather than 3-1-3-3.