Myrsidea fasciata Sychra & Kounek sp. nov.

(Figs 1, 2 A–B)

Type host. Campylorhynchus fasciatus (Swainson, 1838) – Fasciated cactus-wren.

Type locality. Peru, Cascay near Huanuco, 1845 m a.s.l., 9°50'S, 76°80'W.

Type material. HOLOTYPE: ♀ (MMBC), labelled ‘ O. Sychra PE01 / Myrsidea fasciata / Sychra & Kounek sp. nov . / HOLOTYPE (red) // Campylorhynchus fasciatus / PERÚ: Cascay / near Huanuco / 20.viii.2011 / Literák leg. ’. PARATYPES: 3 ♀♀ 3 33, same label data as holotype except ‘O. Sychra PE01–05’.

Description. Female (n = 4). As in Figs 1A and 2A. Hypopharyngeal sclerites weakly developed (Fig. 1B). Length of dorsal head seta (DHS) 10, 0.070 –0.090; DHS 11, 0.095 –0.100; ratio DHS 10/11, 0.70–0.90. Gula with 5–6 setae on each side. Metasternal plate with 5–6 setae; metanotum not enlarged, with 11–12 marginal setae (all setae are counted). First tibia with 3 outer lateral ventral and 4 dorsal setae. Femur III with 19–20 setae in ventral setal brush.

Tergites not enlarged, tergites II–IV with a slightly convex medioposterior margin each (Fig. 1C). Tergal setae with median gap in each row, and setal numbers as follows (postspiracular setae and short associated setae are included): tergite I, 12–15; II, 17–19; III, 17–18; IV, 16–19; V, 18–20; VI, 17–20; VII, 14–16; VIII, 8–9. Postspiracular setae very long on II, IV, VII and VIII (0.45–0.50); long on VI (0.33–0.43) as well as on I and III (0.26–0.32); short on V (0.13–0.19). Sternal setae: II, 5–6 in each aster, 16–20 marginal setae between asters, 4–6 anterior; III, 25–31; IV, 39–43; V, 35–41; VI, 26–34; VII, 17–20; VIII–IX, 22–27 including 11–14 setae on deeply serrated vulval margin; without medioanterior setae on sternites III–VII. Inner posterior seta of last tergum not longer than anal fringe setae with length 0.06–0.08; length of short lateral marginal seta of last tergum, 0.04–0.05. Anal fringe formed by 36–40 setae on both dorsal and ventral side. Dimensions: TW, 0.45–0.49; HL, 0.29–0.32; PW, 0.32–0.33; MW, 0.45–0.51; AW, 0.73–0.74; ANW, 0.29; TL, 1.59–1.74.

Male (n = 3). As in Fig. 2B. Length of DHS 10, 0.070 –0.080; DHS 11, 0.100; ratio DHS 10 /11, 0.70–0.80. Gula with 5–7 setae on each side. Metanotum with 7–9 setae on posterior margin. Femur III with 14–18 setae in ventral setal brush .

Tergal setae with median gap in each row, and setal numbers as follows: tergite I, 11–12; II, 16; III, 16–17; IV, 17–19; V 17–20; VI 16–18; VII, 14–19; VIII, 10–11. Postspiracular setae very long on II, IV (0.45–0.48); long on VII (0.40); shorter on I, III and VI (0.21–0.26); and short on V (0.11–0.14). Sternal setae: II, 5–6 in each aster, 16–18 marginal setae between asters, 6–8 anterior; III, 23–27; IV, 31–36; V, 39–40; VI, 30–31; VII,20; VIII, 10–11, without medioanterior setae. Genital sac sclerite with a slender subapical projection on each side, a straight or slightly convex posterior margin (not well visible on all males examined), and with a short, dark medioposterior line (Fig. 1D). Dimensions: TW, 0.43–0.45; HL, 0.27–0.29; PW, 0.29–0.31; MW, 0.39–0.41; AW, 0.56–0.58; TL, 1.39–1.48; GW, 0.13; GSL, 0.10–0.11.

Differential diagnosis. Its weakly developed hypopharyngeal sclerites place M. fasciata close to M. whitemani Price, Johnson & Dalgleish, 2008a from Campylorhynchus rufinucha (Lesson, 1838) and M. faccioae Valim & Weckstein, 2013 from Cyphorhinus arada (Hermann, 1783) . Females of M. fasciata can be separated from those of M. whitemani by their smaller number of setae on tergites VI–VII (together 31–36 vs. 39–42) and sternites IV–V (together 74–84 vs. 99–111), shorter postspiracular seta V (0.13–0.19 vs. 0.35) and smaller temple width (0.45–0.49 vs. 0.51–0.53). Males of M. fasciata can be separated from those of M. whitemani by their larger number of setae on tergite VIII (10–11 vs. 8), smaller number of setae on sternite IV (31–36 vs. 40–42) and smaller temple width (0.43–0.45 vs. 0.46–0.47). Females of M. fasciata can be separated from those of M. faccioae by their tergites III–IV having a slightly convex medioposterior margin (vs. straight in M. faccioae), larger DHS 10/11 ratio (0.70–0.80 vs. 0.42–0.46), smaller number of setae on tergite III–IV (together 33–37 vs. 40–41, including postspiracular setae and short associated setae) and sternite VII (17–20 vs. 29). Males of M. fasciata can be separated from those of M. faccioae by their smaller number of setae on tergite V (17–20 vs. 22–23) and sternite VII (20 vs. 29), as well as by a larger temple width (0.43–0.45 vs. 0.41).

A portion of the mitochondrial cytochrome oxidase I (COI) gene of Myrsidea fasciata was sequenced, indicating that the species is highly differentiated (p-distance exceeding 17.5 % in all cases) from other Neotropical Myrsidea .

Etymology. From Latin adjective fasciatus (-a, -um) = banded. The species name is derived from the species name of the type host.

Host. Myrsidea fasciata sp. nov. is the first louse species recorded from Campylorhynchus fasciatus .