Descriptions And Recognition Of Larvae Of Some Northern North American Species Of Ilybius Erichson (Coleoptera: Dytiscidae)
Author
Hicks, B. J.
College of the North Atlantic P. O. Box 60, Carbonear Newfoundland, A 1 Y 1 B 5, Canada & Institute of Terrestrial Ecology, Edinburgh Research Station, Bush Estate, Penicuik, Midlothian, EH 9 0 QB, UK
Author
Larson, D. J.
Department of Biology Memorial University of Newfoundland St. John’s Newfoundland, A 1 B 3 X 9, Canada
text
The Coleopterists Bulletin
2000
2000-03-01
54
1
36
59
journal article
310609
10.1649/0010-065x(2000)054[0036:darolo]2.0.co;2
9d8a79bd-5ec5-449e-9d9d-cec8ee872c0a
1938-4394
4900141
Table 3. Measurements, ratios and number of secondary setae of various anatomical parts of the larvae of three species of Ilybius Erichson. Values are given as means ± SD; number in parentheses represents the number of specimens observed. See text for explanation of abbreviations.| Character | I. biguttulus | I. discedens | | | I. discedens | | I. pleuriticus | |
|---|
| I | II | III | I | II | Character | III | I | II | III |
|---|
| HL | | 1.07 ±.01 (5) | 1.54 ±.09 (5) | 2.09 ±.09 (6) | 0.95 ±.01 (6) | 1.27 ±.04 (5) | HL | | 1.73 ±.03 (6) | 1.18 ±.03 (6) | 1.72 ±.05 (6) | 2.44 ±.05 (6) |
|---|
| HW | | 0.93 ±.06 (5) | 1.39 ±.01 (6) | 1.89 ±.06 (6) | 0.89 ±.01 (6) | 1.16 ±.04 (6) | HW | | 1.53 ±.07 (6) | 1.09 ±.06 (6) | 1.61 ±.04 (6) | 2.29 ±.13 (6) |
|---|
| Temporal spines | | | 7–8 (6) | 6–8 (6) | | 3–4 (6) | Temporal spines | | 3–5 (6) | | 6–8 (6) | 6–8 (6) |
|---|
| LAS | | 0.69 ±.01 (8) | 1.17 ±.02 (6) | 1.79 ±.07 (6) | 0.63 ±.07 (6) | 0.88 ±.04 (6) | LAS | | 1.41 ±.05 (6) | 0.78 ±.02 (6) | 1.34 ±.07 (6) | 2.12 ±.07 (6) |
|---|
| SI | | 0.28 ±.01 (6) | 0.33 ±.02 (6) | 0.34 ±.01 (6) | 0.27 ±.04 (5) | 0.28 ±.01 (4) | SI | | 0.25 ±.02 (6) | 0.30 ±.02 (6) | 0.29 ±.01 (6) | 0.25 ± 0 (6) |
|---|
| UP | | 0.35 ±.02 (8) | 0.52 ±.03 (6) | 0.70 ±.03 (6) | 0.29 ±.01 (6) | 0.37 ±.03 (6) | UP | | 0.48 ±.02 (6) | 0.50 ±.03 (6) | 0.77 ±.05 (5) | 1.09 ±.04 (4) |
|---|
| UT | | 1.39 ±.08 (8) | 1.98 ±.14 (6) | 2.62 ±.2 (6) | 1.06 ±.03 (6) | 1.25 ±.07 (6) | UT | | 1.65 ±.05 (5) | 1.79 ±.05 (5) | 2.58 ±.07 (5) | 3.33 ±.05 (4) |
|---|
| A4 | | 0.16 ± 0 (8) | 0.15 ±.01 (6) | 0.14 ±.01 (5) | 0.15 ± 0 (6) | 0.15 ± 0 (5) | A4 | | 0.15 ±.01 (6) | 0.17 ±.01 (6) | 0.18 ±.01 (6) | 0.18 ±.01 (6) |
|---|
| A3 | | 0.21 ± 0 (8) | 0.26 ±.01 (6) | 0.33 ±.01 (6) | 0.19 ± 0 (6) | 0.23 ±.01 (6) | A3 | | 0.26 ±.02 (6) | 0.24 ±.01 (6) | 0.31 ±.02 (6) | 0.38 ±.01 (6) |
|---|
| HL/HW | | 1.14 ±.07 (5) | 1.12 ±.01 (5) | 1.10 ±.05 (6) | 1.07 ±.01 (6) | 1.09 ±.02 (5) | HL/HW | | 1.13 ±.06 (6) | 1.09 ±.04 (6) | 1.07 ±.02 (6) | 1.07 ±.06 (6) |
|---|
| A4/A3 | | 0.74 ±.02 (8) | 0.60 ±.04 (6) | 0.44 ±.02 (6) | 0.78 ±.02 (6) | 0.64 ±.03 () | A4/A3 | | 0.57 ±.03 (6) | 0.71 ±.02 (6) | 0.60 ±.01 (6) | 0.48 ±.01 (6) |
|---|
| LAS/UT | | 0.51 ±.03 (8) | 0.59 ±.05 (6) | 0.69 ±.06 (5) | 0.60 ±.06 (6) | 0.70 ±.04 (6) | LAS/UT | | 0.86 ±.02 (5) | 0.43 ±.01 (5) | 0.53 ±.02 (5) | 0.63 ±.02 (4) |
|---|
| SI/LAS | | 0.41 ±.02 (8) | 0.28 ±.01 (6) | 0.19 ±.01 (6) | 0.42 ±.10 (5) | 0.32 ±.02 (4) | SI/LAS | | 0.18 ±.02 (6) | 0.38 ±.03 (6) | 0.22 ±.02 (5) | 0.12 ± 0 (4) |
|---|
| UP/UT | | 0.26 ±.01 (8) | 0.25 ±.01 (6) | 0.27 ±.02 (6) | 0.27 ±.01 (6) | 0.30 ±.01 (6) | UP/UT | | 0.29 ±.02 (5) | 0.28 ±.01 (5) | 0.30 ±.01 (5) | 0.33 ±.01 (4) |
|---|
| Metaleg/HW | | 1.90 ±.12 (5) | 1.89 ±.08 (6) | 1.96 ±.11 (8) | 1.63 ±.03 (6) | 1.68 ±.06 (5) | Metaleg/HW | | 1.74 ±.08 (6) | 1.96 ±.07 (6) | 1.87 ±.07 (6) | 1.95 ±.08 (4) |
|---|
| Foreleg (total length) | 1.20 ±.05 (8) | 1.74 ±.06 (6) | 2.35 ±.10 (6) | 1.05 ±.01 (6) | 1.37 ±.04 (6) | Foreleg (total length) | 1.84 ±.05 (6) | 1.42 ±.11 (6) | 1.94 ±.06 (6) | 2.81 ±.08 (5) |
|---|
| Mesoleg (total length) | 1.39 ±.03 (8) | 2.06 ±.08 (6) | 2.90 ±.10 (5) | 1.16 ±.02 (6) | 1.55 ±.05 (5) | Mesoleg (total length) | 2.12 ±.04 (6) | 1.59 ±.10 (5) | 2.32 ±.08 (6) | 3.38 ±.25 (4) |
|---|
| Metaleg (total length) | 1.76 ±.04 (7) | 2.63 ±.12 (6) | 3.70 ±.19 (6) | 1.45 ±.03 (5) | 1.94 ±.09 (5) | Metaleg (total length) | 2.65 ±.05 (6) | 2.13 ±.12 (6) | 3.00 ±.12 (6) | 4.53 ±.12 (4) |
|---|
| ProFE | AV | | 0–1 | 0–1 | | 1 | ProFE | AV | 0–1 | | 0–1 | 1–0 |
|---|
| D | | 4–5 | 4–6 | | 3–5 | D | 4–7 | | 4–5 | 4–6 |
| PV | | 5–9 | 5–9 | | 6–9 | PV | 5–9 | | 8–12 | 8–10 |
| Range | | 10–14 | 10–14 | | 10–14 | Range | 10–14 | | 14–17 | 11–16 |
| ProTB | AV | | 1 | 1 | | 0 | ProTB | AV | 0 | | 0–2 | 1–3 |
|---|
| D | | 1 | 1 | | 0 | D | 0 | | 1 | 1 |
| PD | | 1 | 1 | | — | PD | — | | 1–2 | 1–2 |
| PV | | 0 | 0 | | 0 | PV | 0 | | 0–1 | 0 |
| Range | | 3 | 3 | | — | Range | — | | 3–5 | 3–6 |