Synorthocladius sp. 1

Namayandeh, Armin, Bilyj, Bohdan, Beresford, David V., Somers, Keith M. & Dillon, Peter J., 2012, 3324, Zootaxa 3324, pp. 1-65 : 48-49

Synorthocladius sp. 1

Figs 39A–C

Diagnosis. Small larva 3.0 mm. SI seta simple; premandible with one apical tooth, no brush; antenna 5-segmented, 3 rd segment long, membranous or very lightly sclerotized, blade longer than flagellum, AR 1.0; mandible ( Fig. 39A) with three inner teeth, with inner spine below the large seta subdentalis, no seta interna; mentum ( Fig. 39B) triangular with pair of large projecting median teeth, 4 lateral teeth, at the base a stellate group of long, setae some apically branched; large paddle-shaped VM plates; abdominal segments 7–10, each with alternating (2) simple and (2) plumose setae ( Fig. 39C); anal tubules, tubular longer than posterior parapods.

Notes. The larva closely matches the one described and figured in Simpson & Bode (1980: 59) and Oliver et al. (1978, fig.150). They considered it to be an undescribed species similar to Synorthocladius semivirens (Kieffer) , although, no separating characters were given. There appears to be differences in the form of the median teeth, when compared side by side. Based on reared larvae, in S. semivirens the median teeth are less projecting with broadly tapered sides ( Fig. 39D); whereas, in the undescribed species they are much more elongate with narrowly tapered sides.

Ecology and habitat. Simpson and Bode (1980) classified the species as rheobiontic and found in small to moderate sized rivers, with clean to mildly enriched waters.

Sampling sites. Mississagi and Algonquin Provincial Parks.

Nearctic distribution. Canada: NWT, first Ontario record. USA: New York.