Scapheremaeus cheloniella, Colloff, Matthew J., 2009

Colloff, Matthew J., 2009, Comparative morphology and species-groups of the oribatid mite genus Scapheremaeus (Acari: Oribatida: Cymbaeremaeidae), with new species from South Australia, Zootaxa 2213, pp. 1-46 : 13-16

publication ID	https://doi.org/ 10.5281/zenodo.189889
DOI	https://doi.org/10.5281/zenodo.6212618
persistent identifier	https://treatment.plazi.org/id/4B789008-4848-FFB7-DBCC-3A63B1ADFC05
treatment provided by	Plazi
scientific name	Scapheremaeus cheloniella
status	sp. nov.

Treatment

Scapheremaeus cheloniella View in CoL sp. nov.

( Figs. 4 View FIGURE 4 , 5 View FIGURE 5 )

Dimensions: Length: holotype: 529; paratype: 533. Breadth: holotype: 280; paratype: 293.

Prodorsum. Tuberculate laterally, with rugose pattern of poorly-defined ridges medially between costulae. Rostrum pointed, rostral setae (ro) smooth, curved, ca. 19 long; lamellar setae (le; ca. 16 long) on small tubercles (ca. 5 long) slightly longer than broad, connected by translamella. Costulae well developed, moreor-less parallel, bowed laterally, not extending posteriorly as far as bothridia. Alveoli of interlamellar setae (in) present. Sensillus club-shaped, darkly-pigmented; head ca. 20 broad with tuberculate microsculpture, apex extending beyond prodorsal margin.

Notogaster. Length 430 Μm. Circumdorsal scissure entire, with diagonal extensions into humeral region. Lenticulus present (ca. 38 long, 30 broad). Cerotegument consisting of dark, coarse nodules. Centrodorsal region 398 long, 205 broad; with microsculpture of linearly-arranged tubercles of cerotegument overlaying colliculate plaques. Microsculpture of region lateral of circumdorsal scissure consisting of parallel ridges and troughs posteriorly and scattered tubercles anteriorly. Ten pairs of smooth, spiniform notogastral setae borne on short tubercles; lm and lp positioned on centrodorsal region. Caudal region indented slightly. Lyrifissurae ih, ips and ip arranged radially on posterior half of laterodorsal region.

Ventral region. Epimeral setal formula, numbers of aggenital, anal and adanal setae typical of genus; 6 pairs of genital setae; g 2 offset laterally from g 1. Ventral microsculpture similar to that of centrodorsal region. Lyrifissurae iad in para-anal position.

Lateral aspect. Prodorsal microsculpture composed of round, oval and elongate tubercles arranged in linear patterns. Costulae projecting markedly above surface of prodorsum; tubercle of lamellar seta free of prodorsal surface. Carina an angular ridge ventral of lamella; cusp or free projection absent. Pedotectum I auriculate, covering acetabulum I; pedoctectum II midway between acetabula II and III, apex directly ventral of short humeral spine.

Gnathosoma . Typical of family. Tectum of mentum slight, not extending anteriorly as far as bases of setae a.

Legs. Setal formulae: legs I: 1-4-2(1)-4(2)-14(2); legs II: 1-3-3(1)-3(1)-12(1); legs III: 1-3-2-3(1)-12; legs IV: 1-2-2-3(1)-12. Lengths of leg segments (femur to tarsus): legs I: 100, 33, 67, 32; legs II: 91, 33, 58, 30; legs III: 70, 32, 57, 34; legs IV: 77, 32, 68, 36. Femora I-IV with tuberculate microsculpture on antiaxial surface and series of parallel ridges on paraxial surface; circular porose areas present on paraxial surfaces. Elongate porose area present on paraxial surface of tibia IV. Claws heterotridactylous.

Material examined: Holotype and paratype: pitfall trap, Mallee eucalypt vegetation on dune, 14 km WNW Renmark, 34°07’S 140°37’E, South Australia; coll. A. Lambie, 4-24 July, 1995. Types in ANIC.

Etymology: The specific name, cheloniella , is Latinised Greek for ‘little tortoise’.

Remarks. Scapheremaeus cheloniella sp. nov. can be distinguished from other members of the genus by the following combination of characters: 1) microtuberculate, tesellated centrodorsal microsculpture; 2) a complete circumdorsal scissure with humeral extensions; 3) 10 pairs of setiform notogastral setae, those of the p series on dorsal circumnotogastral plate; 4) alveolus of interlamellar seta present; 5) caudal margin indented; 6) prodorsal microsculpture tuberculate; 7) humeral process short, sub-triangular.

This species is most similar morphologically to S. lambieae in the pattern of the centrodorsal microsculpture, but the latter species has no caudal indentation, a posterior centrodorsal rige with lateral concavities and tuberculate protuberances on either side of the lenticulus.