Parametriocnemus lundbeckii

Parametriocnemus lundbeckii (Johannsen)

Figs 27A–F

Diagnosis. Labrum as in Fig. 27A; SI seta plumose; premandible with 2 apical teeth; antenna (Fig. 27B) 5-segmented, 3 rd segment is shorter than 4 th, LO large enveloping the 3 rd, AR 1.2–1.4; mandible (Fig. 27C) with 3 inner teeth, 2 nd lateral slightly recessed; mentum (Fig. 27D) with two median teeth, and 4 + 1 tiny lateral teeth (occasionally worn off), lateral margins extended posteriorly as a dorsal plate with a black spot (Fig. 27E); ventromental plates raised distally and ending just past setae submenti; posterior end of abdomen as in Fig. 27F; procercus with 7 apical setae; anal tubules tapering, as long or slightly longer than posterior parapods.

Notes. The lava is in agreement with species description given by Simpson & Bode (1980: 56) and larvae reared from another project. This species is similar to the Nearctic P. eoclivus, but the latter has larger antennal LO that extend to segment 4, also AR is higher, (1.9–2.0). The larva of the Palearctic Parametriocnemus stylatus (Kieffer) is very similar to P. lundbeckii. In the Holarctic key (Cranston et al. 1983) the mentum shown (fig. 9.54 A) for this species, correctly interprets the VM plate on the left side, but the “second plate” added on the right side is actually a dorsomental plate connected to the posterolateral extension of the mentum.

Ecology and habitat. Larvae occur in clean streams of piedmont and mountains. This species is not tolerant of high turbidity or low oxygen (Simpson & Bode 1980).

Sampling sites. We found the larvae inhabiting streams in all the provincial parks and districts located in our study area.

Nearctic distribution. Canada: Alberta, Québec, Saskatchewan, first record for Ontario. Greenland. USA: Alabama, Arizona, California, Florida, Georgia, Michigan, New Mexico, New York, North Carolina, Ohio, South Carolina, Texas.