Myrsidea Waterston 1915

Myrsidea sp. 2 Material examined. Ex Leptopogon amaurocephalus Tschudi, 1846 —sepia-capped flycatcher: 2♀, 1♂ Centro URKU, Tarapoto, Perú (06°27'S, 76°21'W), 8 August 2011, I. Literak (MMBC); 4♀, 1♂ San Rafael National Park, Paraguay (26°30'S, 55°47'W), 18 and 20 August 2012, I. Literak (MMBC). Remarks. This is the first record of Myrsidea from Leptopogon amaurocephalus.Our specimens are very close to Myrsidea contopi Price, Hellenthal & Dalgleish, 2005 ex Contopus cinereus (Spix, 1825) from Trinidad & Tobago by the shape of metanotum and tergites of female and similar type of genital sac sclerite in male, but differ by setal counts and dimensions, as follows [data from Price et al. (2005) are in parentheses]: Female (n = 6). Metanotum with 8–11 (8–9) marginal setae. Tergal setae: I, 10–13 (6–8); II, 11–13 (9–11); III, 10–15 (11–13); IV, 9–13 (10–11); V, 9–12 (7–9); VI, 10–12 (7–9); VII, 6–11 (4); VIII, 4–6 (4). Sternal setae: II, with 14–19 marginal setae between asters, 4–7 medioanterior (in total 24 marginal and medioanterior setae); III, 22–24 (19–21); IV, 28–35 (30–32); V, 30–36 (34–35); VI, 25–36 (30); VII, 16–18 (12–14); VIII–IX, 7–11 (22–25 including vulvar setae); and 10–13 setae on deeply serrated vulvar margin. Anal fringe formed by 34–36 (35–36) dorsal setae. Dimensions: TW, 0.44–0.45 (0.43–0.44); HL, 0.29–0.31 (0.31–0.32); PW, 0.27–0.32 (0.27–0.28); MW, 0.39–0.41 (0.42–0.43); AWIV, 0.51–0.54 (0.56–0.58); ANW, 0.20–0.23 (0.20–0.21); TL, 1.40–1.42 (1.32– 1.37). Male (n = 2). Metanotum with 5–9 (7–8) marginal setae. Tergal setae: I, 8–10 (5–6); III, 14–15 (7–11); IV, 11– 15 (6–10); V, 11–14 (6–8); VI, 9–13 (6); VII, 7–15 (4–6); VIII, 5–7 (4). Sternal setae: III, 21 (17–20); IV, 25–30 (23–29); V, 29–32 (28–30); VI, 28–30 (22–27); VII, 16–21 (13–16); VIII, 8–11 (6–7). Genital sac sclerite as in Figs 36–37. Dimensions: TW, 0.37–0.40 (0.40–0.41); MW, 0.32–0.36 (0.36–0.37); AWIV, 0.40–0.44 (0.45–0.46); TL, 1.05–1.18 (1.18–1.23). Remarks. A portion of COI gene was sequenced from specimens of Myrsidea sp. 2 ex Leptopogon amaurocephalus from Paraguay (GenBank MF563537). Comparing our sequence with other known sequences of Neotropical Myrsidea, the divergences exceeded 16% in all cases including those of the two morphologically closest species: M. elaeniae Price, Hellenthal & Dalgleish, 2005 (ex Elaenia flavogaster (Thunberg, 1822), GenBank KF048117), with a p-distance of 19.5%, and M. cnemotriccola Valim & Weckstein, 2013 (ex Cnemotriccus fuscatus, GenBank KF048124), with a p-distance of 20.6%, both from species of Tyrannidae. The closest species was M. lightae Valim & Weckstein, 2013 from the Cardinalidae (GenBank EU289211), with a pdistance of 16.9%. These results show that our specimens differ from all Neotropical Myrsidea with known sequences of COI. Despite some morphological differences (especially the smaller number of setae on tergite I in both sexes), we found our specimens to be very close to M. contopi. However, molecular data from M. contopi from the type-host are necessary to confirm that our samples belong to M. contopi. Also, more morphological and genetic data are needed to evaluate the status of Myrsidea from Leptopogon amaurocephalus from different localities, especially because our single males from Paraguay and Perú show some differences in tergal setae (tergites VI–VII of male from Perú with 7–9 setae vs 13–15 in male from Paraguay) and measurements (TW 0.40 for male from Perú vs 0.37 for male from Paraguay). According to these characters, the male from Perú is conspecific with M. contopi, while the specimen from Paraguay could represent a separate species or subspecies. However, the male from Paraguay share the same shape of male genital sac sclerite with M. contopi, while that from Perú differs in this character (see Figs 36 and 37), but such difference maybe the result of a distortion. Contrary to Price et al. (2005), we think that it is not possible to use the tip of the male genital sac sclerite as a single character to separate species of Myrsidea. Although both host species (Contopus cinereus and Leptopogon amaurocephalus) are not closely related (Rheindt et al. 2008), they have almost the same geographical distribution (Clements et al. 2017), implying that host-switching of lice between these host species (see Price et al. 2003) is a possible explanation for the unusual host distribution of these specimens of Myrsidea.
Published as part of Kolencik, Stanislav, Sychra, Oldrich, Papousek, Ivo, Kuabara, Kamila M. D., Valim, Michel P. & Literak, Ivan, 2018, New species and additional data on the chewing louse genus Myrsidea (Phthiraptera: Menoponidae) from wild Neotropical Passeriformes (Aves), pp. 401-431 in Zootaxa 4418 (5) on page 423, DOI: 10.11646/zootaxa.4418.5.1, http://zenodo.org/record/1244956
{"references":["Price, R. D., Hellenthal, R. A. & Dalgleish, R. C. (2005) The genus Myrsidea Waterston (Phthiraptera: Menoponidae) from tyrant-flycatchers (Passeriformes: Tyrannidae), with descriptions of 13 new species. Zootaxa, 1048, 1 - 20.","Valim, M. P. & Weckstein, J. D. (2013) A drop in the bucket of the megadiverse chewing louse genus Myrsidea (Phthiraptera, Amblycera, Menoponidae): ten new species from Amazonian Brazil. Folia Parasitologica, 60, 377 - 400. https: // doi. org / 10.14411 / fp. 2013.040","Rheindt, F. E., Norman, J. A. & Christidis, L. (2008) Phylogenetic relationships of tyrant-flycatchers (Aves: Tyrannidae), with an emphasis on the elaeniine assemblage. Molecular Phylogenetics and Evolution, 46, 88 - 101. https: // doi. org / 10.1016 / j. ympev. 2007.09.011","Clements, J. F., Schulenberg, T. S., Iliff, M. J., Roberson, D., Fredericks, T. A., Sullivan, B. L. & Wood, C. L. (2017) The eBird / Clements checklist of birds of the world: v 2017. Available from: http: // www. birds. cornell. edu / clementschecklist / download / (accessed 14 June 2017)"]}