Eueremaeus granulatus (Mihelčič)

Badamdorj, 2003, The soil mite family Eremaeidae (Acari: Oribatida) in Mongolia, with remarks on distribution and diversity of known genera, Journal of Natural History 37, pp. 1571-1610: 1583-1586

publication ID

1464-5262

persistent identifier

http://treatment.plazi.org/id/6C3CB436-E650-FFF8-3E6A-A332FE7E645D

treatment provided by

Felipe

scientific name

Eueremaeus granulatus (Mihelčič)
status

 

Eueremaeus granulatus (Mihelčič)  

(figure 8)

Eremaeus granulatus Mihelčič, 1955: 308   , figure 3; 1963: 596.

Eremaeus figuratus Winkler, 1956: 308   ; Mihelčič, 1963: 596.

Eremaeus silvestris Forsslund, 1957: 213   , figures 7–10.

Eueremaeus silvestris (Forsslund)   : Mihelčič, 1963: 585, figure 3; Rajski, 1967: 154; Bulanova- Zachvatkina, 1967: 173, pl. 11, figure 166; 1975: 160, figure 307; Marshall et al., 1987: 162.

Eueremaeus granulatus (Mihelčič)   : Pérez-Iñigo, 1970: 301, figures 52–54.

Diagnosis. Medium in size (565–584 m m); costulae relatively short, thin, nearly parallel or very slightly diverging anteriorly and posteriorly, transcostular ridge absent or very weakly developed; sensilli relatively long, thin, slightly expanded distally; interlamellar setae relatively long, attenuate, finely barbed; tubercles La large, situated posterior to each bothridium; 10 pairs of thin, finely barbed notogastral setae; five or six pairs of anal and five pairs of adanal setae; postanal process nearly V-shaped; posteromarginal sclerite not evident; genu III with seta d coupled with solenidion s.

Measurements. Body length 565–584 (575) m m; length of notogaster 384–392 (388) m m; width of notogaster 304–326 (315) m m. Two specimens were measured.

Integument. Body colour yellowish brown. Surface of body and basal part of leg segments with thin cerotegument. Microtuberculate on prodorsal tubercles, interlamellar region and around leg acetabula. Notogaster and ventral plate weakly foveate.

Prodorsum. Rostrum rounded in dorsal view, but distinctly projecting anteroventrally in lateral view. Rostral seta thin, 44–50 m m long, barbed. Lamellar seta thin, longer than ro (54–60 m m), barbed. Costula about 38–46 m m long, thin, nearly parallel or slightly diverging anteriorly and posteriorly; transcostular ridge absent or very faintly developed; minimum distance between costulae about same or slightly greater than half costular length. Shape of costulae somewhat variable. Interlamellar seta 38–40 m m long, weakly barbed, attenuate, directed anterolaterad. Distance between bases of in–in slightly greater than that of ro–ro. Exobothridial seta 20–22 m m long, smooth, directed anterolaterad. Sensillus relatively long (114– 120 m m), thin, barbed in distal two-thirds, slightly expanded distally. Tubercle La large, situated posterior to bothridium (figures 8A, B).

Notogaster. Oval, about 1.2 times as long as wide; relatively flat in lateral view and slightly flattened anteriorly. Anterior margin almost straight, posterior margin broadly rounded in dorsal view. Humeral projection poorly developed. Ten pairs of relatively long (70–82 m m), finely barbed notogastral setae; setae of ps series shorter (40–46 m m) than others. Opisthosomal gland opening (gla) and lyrifissures ia, im, ih, ips and ip well developed. Posteromarginal sclerite not evident (figure 8A).

Gnathosoma   . Infracapitular mentum slightly longer than wide, without noticeable microtubercles. Hypostomal setae h and a medium long, thin; seta m longer and thicker than others, all smooth (figure 8C). Chelicera and palp normal for family, similar to those of E. hepaticus   ; palpal setation: 0-2-1-3-9(1).

Epimeral region. Sejugal, II and III apodemes well developed, aligned obliquely and nearly parallel to one another. Epimeral setal formula 3-2-3-3, all setae smooth. Discidium rounded distally (figure 8C).

Ano-genital region. Genital aperture nearly elongate pentagonal, slightly widened anteriorly, longer than wide; anal aperture widened posteriorly. Six pairs of genital, one pair of aggenital, five or six pairs of anal and five pairs of adanal setae. All ano-genital setae smooth. One of two specimens examined had five pairs, the other six pairs of anal setae. Preanal organ well developed long. Postanal process nearly V-shaped (figure 8C, D).

Legs. Measurements of leg segments given in table 3. Seta d present on genu III coupled with solenidion s; genua I, II and tibiae I–IV without setae d. Formula of leg setation (including famulus) I (1-5-3-4-19), II (1-5-3-4-17), III (2-3-3-3-15); 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). Structure and setation of legs typical for genus and similar to those of former species.

Material examined. One specimen (male): Mt Bulgan, District Erdenebulgan, Province Arkhangai, litter of birch forest ( Betula platyphylla Sukatchev, 1911   ), 48°20∞N, 101°25∞E, elevation 1840 m, 18 May 1996; one specimen (male): Mt Khangai, District Bulgan, Province Arkhangai, litter of larch forest ( Larix sibiricus Ledebour, 1833   ), 47°10∞N, 100°40∞E, elevation 2300 m   , 24 June 1990, Leg. B. Bayartogtokh.

Remarks. The character states of Mongolian specimens are well in accord with those of European material given in the description or redescription by Mihelčič (1955, 1963), Forsslund (1957), Bulanova-Zachvatkina (1967, 1975) and Pérez- Iñigo (1970). Forsslund (1957) illustrated six pairs of adanal and five pairs of anal setae, but mentioned five or six pairs of adanal setae in the description. Later, Mihelčič (1963) and Pérez-Iñigo (1970) illustrated only five pairs of setae on both the anal and adanal plates. In the specimens examined here I found only five pairs of adanal setae, but the number of anal setae was variable (five or six pairs). Thus, the number of anal and adanal setae and the shape of costulae are considered variable characters in this species.

Eu. granulatus (Mihelčič, 1955)   has been confused in the literature since Mihelčič (1963) problematically proposed this species as a junior synonym of Eu. silvestris (Forsslund, 1957)   . Mihelčič’s description had been published prior to Forsslund’s work (the journal issue of the latter work was numbered by two different years as 1956 and 1957). Thus, according to article 23.1 of International Code of Zoological Nomenclature, Eu. granulatus   should have priority over Eu. silvestris   .

Distribution. This is a widely distributed species in Europe and also is recorded from some regions of Asia. Reeves (1967) recorded this species in North America, but Behan-Pelletier (1993) considered that this record might have been based on a misidentification.

Kingdom

Animalia

Phylum

Arthropoda

Class

Arachnida

Order

Sarcoptiformes

Family

Eremaeidae

Genus

Eueremaeus

Loc

Eueremaeus granulatus (Mihelčič)

Badamdorj 2003
2003
Loc

Eremaeus silvestris

Forsslund 1957: 213
1957
Loc

Eremaeus figuratus

Winkler 1956: 308
1956
Loc

Eremaeus granulatus Mihelčič, 1955: 308

Mihelcic 1955: 308
1955