Demodex phocidi (Acariformes: Demodecidae) from Phoca vitulina (Carnivora: Phocidae) – the second observation in the world and a supplement to the species description
, , and | Mar 06, 2020
About this article
Article Category: Research Article
Published Online: Mar 06, 2020
Page range: 49 - 55
Received: May 27, 2019
Accepted: Jul 26, 2019
DOI: https://doi.org/10.1515/ohs-2020-0005
© 2020 Faculty of Oceanography and Geography, University of Gdańsk, Poland
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Figure 1
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Figure 3
Density of Demodex phocidi found in the skin of Phoca vitulina
| Body region | Number of parasites in the examined skin samples | Mean density/1 cm2 of skin |
|---|---|---|
| Hairy skin of the head | 373 | 46.6 |
| Regions of the neck | 181 | 45.3 |
| Back and abdomen | 580 | 36.3 |
| Fore-flippers | 117 | 29.3 |
| Hind-flippers | 40 | 10.0 |
| Tail | 4 | 1.0 |
| Total | 1295 | 32.4 |
Metrical features (micrometers) of Demodex phocidi immatures collected from Phoca vitulina in the Baltic Sea in comparison with the original description
| Feature | Present | |||||
|---|---|---|---|---|---|---|
| Larva |
Protonymph |
Deutonymph |
Larva |
Protonymph |
Deutonymph |
|
| Gnathosoma length | 12 (10–13), SD 1 | 12 (11–13), SD 1 | 14 (13–20), SD 2 | 14 (13–15) | 15 (15–16) | 14 (12–15) |
| Podosoma length | 31 (18–44), SD 6 | 37 (28–48), SD 5 | 49 (38–58), SD 5 | 35 (32–37) | 40 (37–43) | 56 (47–60) |
| Opisthosoma length | 44 (28–55), SD 6 | 71 (55–100), SD 13 | 95 (68–118), SD 13 | 46 (37–59) | 89 (84–93) | 96 (62–116) |
| Gnathosoma width | 12 (10–16), SD 1 | 14 (11–20), SD 2 | 17 (13–23), SD 2 | 17 (16–18) | 17 (15–19) | 18 (16–21) |
| Podosoma width | 26 (15–38), SD 5 | 31 (25–40), SD 4 | 37 (28–50), SD 5 | 26 (21–29) | 29 (26–35) | 35 (29–41) |
| Opisthosoma width | 23 (15–35), SD 4 | 28 (23–35), SD 4 | 32 (23–48), SD 5 | 23 (21–25) | 26 (23–31) | 30 (24–37) |
| Opisthosoma length to body length ratio (%) | 50 (42–56), SD 3 | 59 (51–68), SD 4 | 60 (52–65), SD 3 | 48a | 62a | 58a |
| Body length to width ratio | 3.4:1 (2.2–4.6:1), |
4.0:1 (2.7–5.3:1), |
4.4:1 (3.3–5.7:1), |
3.7:1b | 5.0:1b | 2.9:1b |
| Total body length | 87 (63–110), SD 12 | 120 (97–148), |
158 (120–191), |
96 (82–109) | 144 (135– |
165 (128– |
Metrical features (micrometers) of Demodex phocidi adults and eggs collected from Phoca vitulina in the Baltic Sea in comparison with the original description
| Feature | Present | |||
|---|---|---|---|---|
| ♂(n=100) | ♀(n=100) | ♂(n=12) | ♀(n=20) | |
| Gnathosoma length | 13 (11–15), SD 1 | 15 (11–18), SD 1 | 13 (12–13) | 15 (15–16) |
| Podosoma length | 47 (40–58), SD 4 | 55 (43–63), SD 4 | 43 (40–46) | 52 (47–54) |
| Opisthosoma length | 114 (90–138), SD 11 | 137 (100–175), SD 17 | 115 (103–134) | 117 (104–134) |
| Gnathosoma width | 16 (13–20), SD 2 | 18 (13–22), SD 2 | 17 (15–19) | 19 (18–22) |
| Podosoma width | 38 (28–50), SD 4 | 45 (33–53), SD 4 | 36 (32–40) | 45 (40–49) |
| Opisthosoma width | 34 (25–43), SD 4 | 38 (28–48), SD 4 | 27 (24–29) | 33 (29–38) |
| Vulva length | – | 8 (7–13), SD 1 | – | 7 (6–7) |
| Aedeagus length | 21 (18–28), SD 2 | – | 18a | – |
| Opisthosoma length to body length ratio (%) | 65 (59–70), SD 3 | 66 (60–71), SD 3 | 67b | 67b |
| Body length to width ratio | 4.6:1 (3.4–5.6:1), SD 0.5:1 | 4.6:1 (3.7–6.2:1), SD 0.5:1 | 4.8:1c | 3.9:1c |
| Total body length | 173 (148–202), SD 11 | 207 (159–249), SD 19 | 172 (162–193) | 174 (169–203) |
| Egg | 59 (50–65), SD 4 x 30 (23–36), SD 3d | 57 (53–60) × 31 (29–32)e | ||
| Egg length to width ratio | 2.0:1 (1.7–2.6:1), SD 0.2:1 | 1.8:1f | ||