Atractides

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 : 233-234

ATRACTIDES INTERMEDIUS ( SOAREC, 1939)

Megapus nodipalpis intermedius Soarec, 1939 separate species, Motaş & Tanasachi, 1962

Species dubia

Type series: Missing. Locus typicus: Pârâul Secu. (Leg. J. Soarec 1938) 2 ♂, 1 ♀. Further records published by Soarec (1942), not referring to type material: Carpathes orientales: Bassin du Siret, Bistritza au confluent de Bicaz 550 m, 8 août, 1939; Bassin de la Moldova-Monts de Neamtz, Ruisseau Secu, affl. de l’Ozana, Monastère Secu 500 m, 3 août, 1939; Monts Vrancei et Monts Harghita; Rivière Olt, à Sfântul Gheorghe 500 m 12 juillet, 1939 .

Description. Male (detailed description, 1942, female unknown): idiosoma L/W 540/410 Mm; coxae with completely fused Cx-1–4 (no separating suture line visible between Cx-2 and -3); I-L-5 dL 174, L/W S-1 75/7, S-2 65/? (Soarec: 75 surely erroneous), setal interspace 22 Mm; I-L-6 L 148 Mm, strongly curved, L ratio I-L-5/ 6 1.18; genital field L 171 (Soarec: W = 109 surely erroneous, Fig. 94 shows a genital field wider than long), with equally convex anterior and indented posterior margins; gnathosoma vL 104; palp measurements not usable (strong contradictions between published values, with L P-2 = 74 Mm, P-3 = 50 Mm, but in Fig. 93 both segments nearly equal in L); P-2 with strongly protruding ventrodistal edge, P-4 inflated and with dense dorsal hair cover, sword seta arranged distally from the distoventral hair.

Discussion: Soarec’s first description was a brief diagnosis, without measurements and drawings, and without specification of the sex of the treated specimens, designating it an intermediate variety between A. fonticolus and A. pennatus . The description provided in 1942 was based on three males from three different collecting sites, obviously not including the types, without making any reference to females. A. intermedius has not been recorded since the original description which leaves many open questions and creates additional problems due to obvious measurement mistakes. The diagnosis is based on a juvenile (excretory pore close to posterior idiosoma margin, inflated P-4). This could be the reason for Cx-2 + 3 appearing fused to each other because in juveniles they can be closely examined without encountering the strip of membranous integument separating the two plates in older specimens. A. intermedius is similar to A. fonticolus both in the shape of palps and genital field, and in the shape and position of S-1 and -2 (but following Soarec S-2 less thickened than in A. fonticolus ). Further differences concern the generally lower measurements and differing dimensions of I-L-5 and -6; a low ratio of 1.18 (from this point, Soarec’s measurements and drawing agree) is not found in any of the nodipalpis - like Atractides species.

In view of the numerous obvious errors in the original description, the loss of the types and the fact that A. intermedius was probably described from juveniles, this taxon should be considered a species dubia. However, the name could be ‘reanimated’ if in the type region fonticolus -like Atractides with a low L ratio I-L- 5/6 are found.

Figures

Figure 93. Atractides orghidani, Sicily. A, ♂ I-L-5 and -6, posteriorly; B, ♂ palp, medial view; C, ♀ I-L-5 and -6, anteriorly; D, ♀ genital field and right Vgl-3/4; E, ♂ ventrum, partial view. Scale bars = 100 µm.

Figure 94. Atractides hystricipes. A, D, G, H, holotype ♂ SMNH 2898; B, C, E, F, paratype ♀ SMNH 2899. A, ♂ I-L; B, ♀ I-L; C, ♀ palp, medial view; D, ♂ palp, medial view; E, ♀ Vgl-1/2 and excretory pore; F, ♀ genital field; G, ♂ coxal field; H, ♂ genital field. Scale bars = 100 µm.