Jugatala angulata

Bayartogtokh, B. & Schatz, H., 2008, Trichoribates and Jugatala (Acari: Oribatida: Ceratozetidae) from the Central and Southern Alps, with notes on their distribution, Zootaxa 1948, pp. 1-35 : 24-27

Jugatala angulata (C. L. Koch, 1839)

(Figs. 13, 14)

Oribates angulatus C. L. Koch 1839, fasc. 30(21).

Jugatala angulata : Sellnick 1928, p. 11, fig. 14; Willmann 1931, p. 158, fig. 283; Weigmann 2006, p. 387, fig. 207c, d, e.

Diagnosis. Rostrum broadly rounded, without lateral dens, with a nose-like protuberance dorsally; all prodorsal setae finely barbed; lamella narrow, with long, but thin translamella; lamellar cusp short, blunt at tip, without distinct dens; sensillus short, with smooth capitate head; tutorium very narrow, gradually narrowed firom basis to distal end and pointed distally; 11 pairs of notogastral setae of medium length, relatively thick, blunt at tip, barbed, dp present; porose areas round to oval; lenticulus absent; adanal setae barbed, much thicker than other ventral setae.

Measurements. (n = 1) Body length 486 µm; length of notogaster 403 µm; width of notogaster 312 µm.

Integument. Body colour yellowish brown. Cerotegument thin, roughened by reticulate granules, forming a network-like structure on the notogaster. Faintly microtuberculate on cuticle of prodorsum, ventral plate, leg segments and subcapitular mentum.

Prodorsum (Fig. 13A, B, D). Rostrum broadly rounded, smooth, without lateral dens, with a nose-like protuberance dorsally. All prodorsal setae finely barbed; rostral seta slightly longer than others; interlamellar seta just reaching end of lamellar cusp. Lamella narrow, with long, thin translamella; lamellar cusp short, blunt at tip, without distinct dens (Fig. 13B). Sensillus short, with smooth capitate head. Bothridium small, with slightly pointed bothridial scale svm. Tutorium very narrow, gradually narrowed firom its basis to distal end, and sharply pointed distally, just reaching alveolus of rostral seta (Fig. 13D).

Notogaster (Figs. 13A, D, 14A). About 1.3 x longer than wide. Notogastral surface covered by cerotegument with reticulate granules, forming a network-like structure. Anterior margin of notogaster arched anteriad, lenticulus absent. Pteromorph small, curved ventrally. Eleven pairs of notogastral setae, dp present, all setae relatively thick, blunt at tip, barbed. Porose areas small, round to oval, Aa and A1 larger than A2 and A3. Lyrifissures ia, im, ih, ips, ip and opisthosomal gland opening small.

Gnathosoma (Fig. 13C). Subcapitular mentum conspicuously wider than long, with microtubercles. Hypostomal setae a, h, m of medium length, thin, smooth. Palp and chelicera typical for family as those in the next species.

Epimeral region (Fig. 13C). Epimeral setae thin, smooth; seta lc conspicuously longer and thicker than other setae, setal formula 3-1-3-3. Custodium short, not reaching anterior margin of pedotectum II; discidium conspicuously projecting laterally.

Ano-genital region (Figs. 13C, 14A). Anal and genital apertures nearly equal in size, anal and genital plates smooth. Genital, aggenital and anal setae thin, smooth, adanal setae barbed, much thicker than other ventral setae; adanal lyrifissure iad short. Postanal porose area narrowly elongate, longer than distance between bases of adanal setae ad2 (14A).

Legs (Fig. 14 B–E). Medial claw slightly thicker than lateral claws. Formula of leg setation (including famulus): I (1-5-3-4-20); II (1-5-3-4-15); III (2-3-1-3-15); IV (1-2-2-3-12); formula of solenidia: I (1-2-2); II (1-1-2); III (1-1-0); IV (0-1-0). Most leg setae distinctly barbed, except (p) and (u) on tarsi I–IV. Setae l ” on tibiae and genua I–IV thicker than other setae, heavily barbed.

Material examined. Austria, East Tyrol, Kalser Dorfertal - Daberklamm , in moist moss on rock (1820 m a.s.l., 17 August 1989: 1 female, leg. H. Schatz).

Remarks. The character states of the present specimen agree with those of the material examined by Sellnick (1928) and Weigmann (2006). The only observed differences are the body size – our specimen is smaller (length 486 µm) than the specimens studied by the other authors (520 – 665 µm), and the notogastral setae in our material are thick and blunt rather than thin and pointed.

Willmann (1953) described Jugatala rotunda (with a question mark on generic placement of his newly described species) from "Toten Gebirge" in the Eastern Alps, later found in Moravia, Czech Republic, and is a species very similar to J. angulata . According to the description and the figure given by Willmann, the shape of the lamellae, the lamellar cusps, the size of prodorsal setae, the shape of sensilli, and the reticulate structure of the notogaster are identical to those of J. angulata . The main differences of J. rotunda are a relatively wide and almost circular notogaster, and thin, smooth notogastral setae, but these characters might be in the intraspecific variation range as mentioned above. In this respect, J. rotunda might be a possible junior synonym of J. angulata , but the examination of type material is required.

The two pairs of adalar porose areas illustrated by Willmann seem to be improbable. Sellnick (1928) and Willmann (1953) stated that the genus Jugatala is characterized by a waved posterior part of the notogaster ( “ Abdomen gegen das Ende hin gerunzelt und dort mit mehr oder weniger kegeligen Erhöhungen, die symmetrisch auftreten ”). This specific character is not mentioned in Willmann (1931) and Sellnick (1960), nor in Balogh (1972) or later publications. On the other hand, Willmann (1931) mentioned this character in his key for J. angulata , and according to Sellnick (1960) the waved posterior edge occurs occasionally in that species, but Weigmann (2006) did not mention it. It should also be mentioned that in some studied specimens of J. angulata the porose areas A3 or rarely both A2 and A3 are on small tubercles as shown by Behan-Pelletier (2000) in J. tuberosa Ewing, 1913. Starý (2000b, 2006) reported J. rotunda in the faunas of Czech and Slovak Republics, based on published or unpublished data by other researchers.

Distribution. Jugatala angulata is a Central European species, and until the present time it has been recorded in Germany, Poland, Czech and Slovak Republics, Austria, Northern Italy (Provincia di Trento) and Slovenia (Tarman 1983; Olszanowski et al. 1996; Schatz & Gerecke 1996; Weigmann 2006; Starý 2000a, 2000b, 2006).