Atractides tuberosus

Gerecke, Reinhard, 2003, Water mites of the genus Atractides Koch, 1837 (Acari: Parasitengona: Hygrobatidae) in the western Palaearctic region: a revision, Zoological Journal of the Linnean Society 138, pp. 141-378 : 192-193

ATRACTIDES TUBEROSUS (K. VIETS, 1919)

Megapus tuberosus K. Viets, 1919

Species dubia

Type series: Holotype ♀ SMF 2116 Atractides tuberosus (Viets) ♀ Type Oelkassen a. Vogler Wabach 4.9.1911. Viets coll. 2116. State of conservation: mounting medium with numerous precipitations covering the subjects; dorsum/ventrum lying separate, both I-L and both palps separate, in lateral view.

Material examined: NHMB ♂ without collecting site indication, ex coll. Piersig Megapus tuberosus Walter. ; Typus; = walteri IIX /38–39, Pr.479–479a idiosoma and gnathosoma on separate slides. Walter planned to describe this specimen under the preoccupied name of tuberosus ; some years later it became the type of A. walteri (K. Viets, 1925) .

Description. Female (original description and holotype): idiosoma total L 660, W 420 Mm; integument finely lineated (8/10 Mm) 15 Mm thick, Dgl diameter 27 Mm; coxae rather slender, W on the level of Cx- 4360 Mm, gnathosomal bay L 100, central W 55 Mm, Cx-3 L 215 Mm; legs, mainly I-L, with numerous nodule-like formations; I-L-5 dL 150, HB 40, I-L-6 dL 115 Mm distally little enlarged; genital field L 165, W 150 Mm, gonopore L 150, genital plates L 90, Ac-3 L 30 Mm, Ac arranged in a curved line, pregen rather large; chelicera total L, 195, claw L 50 Mm palp measurements (L/H, P-1–5): 25/22, 61/47, 78/43, 96/31, 29/ 11 Mm; P-4 ventrally straight, dorsally equally convex, ventral hair insertions dividing the segment into three equal parts, sword seta in the centre of the segment; numerous, more or less hemispheric swellings at or near the insertions of the numerous fine hairs (as in A. tuberipalpis (K. Viets, 1913) from Cameroon) a few such nodules also at the terminal segment of the palp.

Discussion: The field of densely arranged dorsal setae on P- 4 in Atractides is possibly associated with glandular activity. Specimens with droplets accumulated in that area are found frequently in several species. It is clearly visible in the holotype that the nodules after which it is named are not projections from the sclerotized integument of the segment; they vary in size and are more or less detached from the integumental surface.

Since the first description, only a few finds of A. tuberosus have been published (Schwoerbel, 1959; Bader, 1975) and K. Viets & K. O. Viets (1960) designated it species incerta. From the drawings published by Bader (1975) who gave the first description of a male, one can deduce that he examined specimens of A. vaginalis covered with oil-like droplets. The completely different shape of the genital field of his females confirms that his specimens do not belong to what the Viets called A. tuberosus . As the preparation is in a poor state of conservation, and the species description was based on a single female, it makes little sense to discuss it if it represents one of the species described later on. I consider A. tuberosus a species dubia.

ATRACTIDES FONTICOLUS (K. VIETS, 1920)

( FIG. 26A–G )

Megapus nodipalpis fonticolus K. Viets, 1920

separate species: Georgiev, 1957

Syn. A. soproniensis ( Szalay, 1929) : syn. nov.; A. petkovskii Schwoerbel, 1963 : syn. nov.

Type series: Lectotype ♂, here designated: SMF 2542 Type; Bremen. Stoteler Wald , 25.7.1919. Nord-Quelle. Viets leg. State of conservation: good, mounting medium with large crystals; the preparation contains two specimens, one entire, and one dissected: idiosoma entire, gnathosoma and one chelicera in situ, one chelicera missing, both palps separate, laterally, left I-L- and III-L separate, but not in horizontal position, Gsk separate, in posterior view; the dis-sected specimen is designated as lectotype . Paralectotypes (further specimens from the locus typicus, but collecting date 29.5.1920; as the publication appeared in August 1920, they can be considered as syntypes): SMF 6279 , 1 ♂, 1 ♀. Loci typici of the original description: springs at the Ratzeburger See and near Bremen .

Material examined: Germany, Bühlertal ( TÜ) Hungerbrunnenbach, 22.8.1984, 1 ♂, 1 ♀, Gerecke .

Description:

General features dorsal integument: lineated (4–5/10); muscle attachments: unsclerotized I-L: I-L-5 longish, dorsal and ventral margins subparallel, S-1 and -2 closely to each other, S-2 extremely enlarged I-L-6 relatively short, sausage-shaped, genital field: Ac in an obtuse triangle, subtriangular in shape excretory pore: smooth; Vgl-1: sexual dimorphism, fused to Vgl- 2 in males,

separate in females palp: strong sexual dimorphism

Males

Paralectotype SMF 6279, in parentheses specimen from south-west Germany genital field: anterior margin convex, posterior margin deeply indented; genital setae: 60 palp: ventral margin P-2 laterally nose-like extended, medially with a more strongly projecting truncate and irregularly rough protrusion, P-3 slightly concave, P-4 maximum H near insertion of the proximoventral hair,

1: 1: 1, sword seta curved, on the level of the distoventral hair idiosoma L/W 660/530; glandularia 28 coxal field L 350; Cx-3 W 405; Cx-1 + 2 mL (105), IL (250), W (305) I-L-5 dL 192, vL 154, dL/vL 1.25, HA-HC 45, 52, 73, dL/HB 3.69 S-1 L 73, L/ W 9.1, S-2 L 55, L/ W 3.9, interspace 12, L S-1/2 1.33 I-L-6 L 111, HA-HC 25, 22, 24, dL/HB 5.04; L I-L-5/6 1.73 genital field L/W 121/134, Ac-1–3 L 35, 41, 38 gnathosoma vL 148; chelicera –

Figures

Figure 26. Atractides fonticolus. A, paralectotype ♂, B–D, lectotype ♂, E-G paralectotype ♀. A, ♂ I-L-5 and -6; B, ♂ genital field; C, ♂ palp, lateral view; D, ♂ palp, medial view; E, ♀ genital field; F, ♀ palp, medial view; G, ♀ palp, lateral view. Scale bars = 100 µm.