Hesperoperla hoguei

Sandberg, John B., 2009, Vibrational Communication (Drumming) Of The Western Nearctic Stonefly Genus Hesperoperla (Plecoptera: Perlidae), Illiesia 5 (13), pp. 146-155 : 150

Hesperoperla hoguei – New Signal Description

Hesperoperla hoguei was recorded and analyzed in 2006 and 2007. Seven call signals were obtained from one male on 01 October 2006, collected live and recorded the same day (Table 2). The typical 13–22 beat call was monophasic ( Fig. 1 ) with 21 mode beats (19.9 3.1), and 240.6 38.5 msec overall average interbeat intervals (Table 2). The mean duration of male calls was 4537 956 msec. The average interbeat interval call pattern indicated by white bars ( Fig. 5A ), decreased over the first five beats (i1–i4), increased gradually with occasional stalls through i16, and then increased more rapidly over the remaining 5 beats (i17–i21). This trend of initial call pattern decrease followed by a gradual increase was observed for both Hesperoperla species ( Figs. 5–6 ), where individual (not overall) averages for each interbeat (i) or intergroup interval (igi) are graphically expressed in bar charts.

In 2007, drumming was analyzed separately for adults that were collected live or reared. Forty-six calls and 23 answer signals were recorded from two males and one female, respectively, field-collected on 21 September and recorded 23 September. The males had call signals with 20 mode beats (20.6 1.2) and overall average interbeat intervals of 188.5 29.7 msec (Table 2). The average male call duration was 3688 285 msec. The female answer signal had 6 mode beats (7.1 2.7) and overall average interbeat intervals of 147.1 47.7 msec. The typical malefemale 2-way exchange was monophasic ( Fig. 2 ) with a mean duration of 6236 255 msec. The average interbeat interval call pattern indicated by gray bars ( Fig. 5B ), decreased over the first 5 beats (i1–i4), and then increased over the remaining 6–23 beats (i5–i22).

Reared H. hoguei adults – Eighty and 64 signals were recorded from three 1–2 day old and one 2–3 day old males and female, respectively, between 29 August and 18 September 2007. The males had call signals with 20 mode beats (17.9 2.6) and overall average interbeat intervals of 149.9 35.9 msec (Table 2). The average male call duration was 2660 476 msec. The female answer signal had 16 mode beats (14.0 2.6) and overall average interbeat intervals of 92.9 27.6 msec. The typical male-female 2-way exchange was monophasic with a mean duration of 5069 512 msec. The average interbeat interval call

pattern indicated by black bars ( Fig. 5C ), increased over the first 22 beats (i1–i21) and then decreased over the last intervals i22–i23. The four individual monophasic calls that made up average intervals i22– i23 had increasing interval patterns.

Figures

Fig. 1. Hesperoperla hoguei 23 beat monophasic male call. Collected from Domingo Spring, Plumas Co., CA, J. Sandberg, October 2006. Arrow = First call beat, a = Interbeat interval 21 (i21) and ♂C = male call.

Fig. 5. Hesperoperla hoguei simple monophasic 13-24 beat call patterns based upon individual average interbeat intervals i1-i23 (msec) for three Domingo Spring analysis groups.A) White bars = 2006 collected male calls (N=7), B) Gray bars = 2007 collected male calls (N=46) and C) Black bars = 2007 reared male calls (N=80). Y-axis ranges from 100-325 msec.

Fig. 2. Hesperoperla hoguei 2-way monophasic exchange. Collected from Domingo Spring, Plumas Co., CA, J. Sandberg, September 2007. ♀= female answer, a = ♂ interbeat interval, b = (♂C-♀) exchange interval, c = ♀ interbeat interval.