Pristina jenkinae ( Stephenson, 1931 )

Schmelz, Rüdiger M., Jocque, Merlijn & Collado, Rut, 2015, Microdrile Oligochaeta in bromeliad pools of a Honduran cloud forest, Zootaxa 3947 (4), pp. 508-526 : 519

Pristina jenkinae ( Stephenson, 1931)

Naidium jenkinae Stephenson, 1931: 39 –41, text fig. 1.

Naidium roseum Piguet. Marcus 1943: 130 –131, pl. 25 fig. 105, pl. 26 fig. 106. Pristina jenkinae (Stephenson) . Sperber 1948: 224 –225. Brinkhurst 1971: 396, fig. 7.23A– B. Timm 2009: 74 –75. Pristina idrensis Sperber, 1948: 220 –222, fig. 23D–F, pl. 20, 21 fig. 1. Timm 2009: 74 –75. Pristinella jenkinae (Stephenson) . Brinkhurst 1985: 472. Kathman 1985: 1022 –1026, fig. 1a–j. Pristina taita Stout, 1956: 99 –101, figs 5–7.

Pristina nothofagi Stout, 1958: 289 –292, figs 1–6.

Material examined. Five specimens, unstained whole mounts, IG 327183-28 to IG 327183-32, [15.497351- 88.21247, 15.513328 -882.1247, 15.530322 -88.27633], 2070 m, 1670 m and 1608 m asl, respectively, M. Jocque 06/08/2013. Two anterior zooids, incomplete posteriorly, two posterior zooids, one specimen complete with regenerating anterior end.

Description. Specimens strongly contracted, ill-preserved, diameter c. 0.24 mm. Prostomium without proboscis. Dorsally one hair and one needle per bundle, needles with parallel teeth, lower c. 2x as thick and long as upper, hair chaetae max. 20 Μm long. Ventral chaetae bifid, 5–7 per bundle anteriorly. Pharyngeal glands in IV, V, discrete packages, stomach in posterior of VI and in VII. Coelomocytes spherical, diameter 6–10 Μm.

Remarks. This cosmopolitan freshwater species has one previous record from bromeliad tanks in Brazil ( Marcus 1943: 131). Specimens were identified as Naidium roseum Piguet but later considered to be P. j e n ki n ae ( Sperber 1948). There are also several records from forest soil habitats (see below, discussion), beginning with Stout's descriptions of P. taita and P. nothofagi from New Zealand, both synonymized with P. jenkinae by Kathman (1985). Several authors ( Marcus 1943; Righi & Hamoui 2002; Van Haaren & Soors 2013) consider P. jenkinae a junior synonym of P. ro s ea Piguet, 1906, but we prefer to follow Timm (2009) who maintains P. jenkinae as a separate species. Comparing the original descriptions ( Piguet 1906; Stephenson 1931), the intestine widens in VIII in P. rosea and in VII in P. jenkinae ; this seems to make a clearcut difference, apart from the much-debated differences in details of the chaetae. The taxonomy of P. jenkinae and its possible synonyms is problematic ( Collado & Schmelz 2001; Righi & Hamoui 2002; Van Haaren & Soors 2013) and in need of revision. The visible details in the Honduras specimens agree with specimens from soil sites in the Brazilian Amazon ( Collado & Schmelz 2001) and the Mata Atlântica (Schmelz, unpublished), studied in vivo and identified as P. jenkinae . In these specimens the stomach widens in the posterior of VI and in VII, and commissural vessels in I–III are simple, not anastomosing; both details disagree with the diagnoses of P. ro s e a ( Piguet 1906; Sperber 1948).