Echiniscus militaris Murray, 1911

Gąsiorek, Piotr & Vončina, Katarzyna, 2023, Atlas of the Echiniscidae (Heterotardigrada) of the World-part I: West Palaearctic Echiniscus species, Zootaxa 5344 (1), pp. 1-72 : 38-40

14. Echiniscus militaris Murray, 1911

Figures 21 , 38

Synonyms

Echiniscus hexacanthus Maucci, 1973 syn. nov., Echiniscus militaris hexacanthus Maucci, 1973 : Pilato (1977)

Echiniscus militaris hystrix Maucci, 1973 : Pilato (1977)

Echiniscus militaris quadrispinosus M. Bertolani, 1946 : Pilato (1977)

Locus typicus: Ireland, County Mayo, Castlebar.

Additional localities: (1) Italy, the Dolomites ( Ramazzotti 1972); (2) Ukraine, Crimea, Yalta ( Pilato 1977); (3) Croatia, Istria, Gračišće ( Maucci 1972); (4) Italy, vicinity of Trieste (Maucci 1973–4); (5) Norway, Nordland, vicinity of Bodø ( Durante Pasa & Maucci 1975b, 1979b); (6) France, Nice ( Séméria 1982); (7) 49°14’38’’N, 19°54’34’’E, 1644 m asl: Poland, the Tatras, Kobylarzowy Żleb ( Gąsiorek & Degma 2018); (8) 46°35’24’’N, 12°52’26’’E, 1485 m asl: Italy, the Carnic Alps, Monte Coglians (see Table 1 ).

Etymology: From Latin militaris = military (probably underlining an abundant chaetotaxy of this species). An adjective in nominative singular.

Shortened description: Variable in body length, small to large (ca. 160–320 μm). Body appendage configuration A-B-Bd- C-Cd- D-Dd- E, most of which are filamentous cirri, only appendages E can be formed as robust spines. High variability of chaetotaxy, but usually cirri B and Bd visibly thinner than the remaining appendages ( Fig. 21A ). Dorsal plate sculpturing comprises large pores with polygonal edges (like in E. granulatus , E. blumi-canadensis complex, or Testechiniscus ). Genital plates present. Dentate collar IV with numerous elongated teeth. Claws long, with primary spurs widely divergent from branches. Larvae with a fully developed set of trunk appendages and dorsal sculpturing only slightly different from that of adults, as pores are faint and may be smaller in anterior portions of pI–II, m2, and the entire m3 ( Fig. 21B ).

Phylogenetic position: The closest relative is E. granulatus , but the nuclear markers failed to uncover them as sister species (Figs 1–2). Instead, E. militaris was inferred as embedded within populations of E. granulatus , yet with considerably longer branch. Unfortunately, COI did not amplify for the sequenced specimens.

Remarks: The species is endemic to the Western Palaearctic, being extremely rare ( Fig. 38 ). The only exception seemed to be the vicinity of Trieste and Istria, where abundant populations were found, and served in distinguishing several subspecies ( Maucci 1972, 1973–4) of a negligible systematic value ( Pilato 1977). Echiniscus hexacanthus Maucci, 1973 syn. nov. should be included within the scope of a considerable intraspecific variability of E. militaris given the lack of separating criteria. The high variability of chaetotaxy, an identical dorsal sculpturing ( Maucci 1986), and elongated claws fully support the close relationship between E. militaris and E. granulatus .

Figures

FIGURE 21. Echiniscus militaris (PCM): A—juvenile (Poland; Gąsiorek & Degma 2018), B—larva (Italy). Scale bars = 20 μm.

FIGURE 38. Records of E. militaris (red circles) and E. lichenorum (yellow circles) from Europe. See Gąsiorek et al. 2022 for extra-European records of E. lichenorum.