Halacarellus Viets 1927

• Main Author: Bartsch, Ilse
• Format: Text
• Language: unknown
• Published: Zenodo 2015
• Subjects: Biodiversity; Taxonomy; Animalia; Arthropoda; Arachnida; Trombidiformes; Halacaridae; Halacarellus; Antarctic; Newell; Antarc*; Mite
• Online Access: https://dx.doi.org/10.5281/zenodo.5696471; https://zenodo.org/record/5696471

Halacarellus Viets, 1927 (Figs 44–46) Type species. Halacarus balticus Lohmann, 1889. Adults. Female and male with GA. Female GA with two to four (rarely seven) pairs of pgs, genital sclerites with zero to five pairs of sgs. Three pairs of internal acetabula always distinct, in freshwater inhabiting species enlarged (Viets 1928 a: fig. 49; Bartsch & Gerecke 2011: fig. 1 H). Acetabula arranged in line along genital slit, anterior pair anterior or posterior to level of mid-GO (Fig. 44; Otto 1994: fig. 27). Ovipositor at rest often extending beyond GO. Ovipositor with two basal and eight or ten apical genital spines. Basal pair of genital spines papilli- or setiform. Apical genital spines dissimilar in shape, robust and with tines, slender and spiniform, or reduced to small papillae (Figs 45, 46; Womersley 1937: pl. 6, fig. 12; Bartsch 1998 b: figs 31, 61, 2007 b: fig. 6 G). Male GA with 10–50 pairs of pgs and in general five pairs of sgs (rarely less). In the majority of species all three pairs of acetabula internal, arranged along genital slit; in a few species (of the H. capuzinus group) three pairs of acetabula arranged in posterior part of GO, within a fovea that opens to the exterior (Bartsch 1998 b: fig. 48). In freshwater species two pairs of gac posterior to GO, enlarged and external, one pair of gac small, near middle of GO (Viets 1928 a: fig. 48; Bartsch 1998 b: fig. 15). AE without epimeral pores. Juveniles. With larva and two nymphal stages. Nymphs of northern hemisphere species with genital and anal plate fused to a GA (e.g. in the type species H. balticus ), most southern hemisphere species with GP and AP separated. Deutonymphal GA with two pairs of pgs, zero to two pairs of sgs and two pairs of gac (Newell 1951: figs 3, 19; Bartsch 1972: figs 25 B, 28 B, 1995 a: fig. 19, 1998 b: figs 24, 41, 63, 82, 101, 1990 c: fig. 137, 1999 c: fig. 3 F). Acetabula of nymphs small and internal, large and internal or large and external (e.g. in H. hyrcanus (Viets, 1928) and H. fontinalis Bartsch & Gerecke 2011 (Bartsch 1998 b: fig. 24; Bartsch & Gerecke 2011: fig. 2 G). Protonymphal GA generally with pair of internal gac; pgs and sgs lacking (Bartsch 1972: figs 25 D, 28 F, 1995 a: fig. 11, 1998 b: figs 44, 85, 1999 c: fig. 3 G). Larva with pair of epimeral pores on AE (Bartsch & Panesar 2000: fig. 3). Larval anal plate often with large ventral part (Bartsch 1972: fig. 25 F, 1998 b: figs 67, 88). Remarks. The genus, with about 50 species, is spread world-wide (Bartsch 2009 a). Several of the species can be assigned to distinct species groups (Bartsch 1997 a). Representatives of the northern Atlantic Ocean groups are not found on the southern hemisphere and vice versa (Bartsch 1997 a). : Published as part of Bartsch, Ilse, 2015, The genital area of Halacaridae (Acari), life stages and development of morphological characters and implication on the classification, pp. 201-259 in Zootaxa 3919 (2) on page 218, DOI: 10.11646/zootaxa.3919.2.1, http://zenodo.org/record/245246 : {"references": ["Viets, K. (1927) Die Halacaridae der Nordsee. Zeitschrift fur Wissenschaftliche Zoologie, 130, 83 - 173.", "Lohmann, H. (1889) Die Unterfamilie der Halacaridae Murr. und die Meeresmilben der Ostsee. Zoologische Jahrbucher, Abteilung fur Systematik, Okologie und Geographie der Tiere, 4, 269 - 408.", "Viets, K. (1928 a) Wassermilben aus dem Schwarzen Meer, dem Kaspischen Meer und dem Aral-See. Abhandlungen. Naturwissenschaftlicher Verein zu Bremen, 27, 47 - 80.", "Bartsch, I. & Gerecke, R. (2011) A new freshwater mite of the marine genus Halacarellus (Acari: Halacaridae) from the Austrian Alps (Styria, Gesause National Park): Description and reflections on its origin. Zoologischer Anzeiger, 250, 151 - 159. http: // dx. doi. org / 10.1016 / j. jcz. 2011.02.003", "Otto, J. C. (1994) New species of Halacaridae from Australia (Acarina: Prostigmata). Acarologia, 35, 31 - 48.", "Womersley, H. (1937) Acarina. Australasian Antarctic Expedition 1911 - 1914, Scientific Reports, Series C, 10 (6), 1 - 24.", "Bartsch, I. (1998 b) Halacarinae (Acari, Halacaroidea) from the northwestern Black Sea: A review. Mitteilungen aus dem Hamburgischen Zoologischen Museum und Institut, 95, 143 - 178.", "Newell, I. M. (1951) New species of Agaue and Thalassarachna from the Aleutians (Acari, Halacaridae). American Museum Novitates, 1489, 1 - 19.", "Bartsch, I. (1972) Ein Beitrag zur Systematik, Biologie und Okologie der Halacaridae (Acari) aus dem Litoral der Nord- und Ostsee. I. Systematik und Biologie. Abhandlungen und Verhandlungen des Naturwissenschaftlichen Vereins zu Hamburg, Neue Folge, 16, 155 - 230.", "Bartsch, I. & Panesar, A. R. (2000) Die Meeresmilbe Caspihalacarus hyrcanus in der Donau bei Wien, ein ponto-kaspisches Relikt. Natur und Museum, 130 (8), 258 - 263.", "Bartsch, I. (2009 a) Checklist of marine and freshwater halacarid mite genera and species (Halacaridae: Acari) with notes on synonyms, habitats, distribution and descriptions of the taxa. Zootaxa, 1998, 1 - 170.", "Bartsch, I. (1997 a) Thalassarachna and Halacarellus (Halacaridae: Acari): two separate genera. Journal of Natural History, 31, 1223 - 1236. http: // dx. doi. org / 10.1080 / 00222939700770661"]}