Myrsidea Waterston

Price, Roger D., Johnson, Kevin P. & Dalgleish, Robert C., 2008, Myrsidea Waterston (Phthiraptera: Menoponidae) from wrens (Passeriformes: Troglodytidae), with descriptions of three new species, Zootaxa 1740, pp. 59-65 : 59-60

Genus Myrsidea Waterston

Myrsidea Waterston, 1915: 12 . Type species: Myrsidea victrix Waterston, 1915 , by original designation.

A thorough characterization of this genus may be found in Clay (1966). We provide here only the characters we have found to be pertinent to the delineation of the genus as it pertains to the wren lice.

Head evenly rounded anteriorly; lacking lateral slit or notch; with long inner and minute outer occipital seta on each side; each temple margin with 4 very long setae; without ventral sclerotized processes; gula with 5, less often 4 or 6, setae on each side with posterior seta heavier and longer than those anterior to it.

Thorax with pronotum lacking central setae; with 3 short setae at each lateral angle and 6 longer medioposterior marginal setae. Mesonotum well defined, with 2 minute medioanterior setae adjacent to postnotum and 2 minute setae at posterior margin. Metanotum ( Fig. 1 ) not enlarged, without central setae, but with 6 short anterior setae around periphery and with very long seta at lateroposterior corner in addition to other marginal setae. Prosternal plate well developed, elongate, with 2 short anterior setae; metasternal plate prominent, diamond shaped; venter of femur III with setal brush.

Abdomen ( Figs. 1, 3 ) having undivided tergites; without anterior setae except for very small seta near lateroanterior corner on each side of tergite I (not included in setal count); all tergal setal rows with pronounced gap in center of each row; sternite I small, without setae; sternite II enlarged, with aster of small number of heavy setae at each lateroposterior corner. Postspiracular setae very long on I (0.23–0.30), extremely long on II, IV, and VIII (at least 0.40). Pleurites without anterior setae. Female anus oval, without inner setae. Female subgenital plate of fused sternites VII–IX; setae given for VII represent those anteriorly located on region of segment VII, and those for VIII–IX are the remainder of the plate setae. Male subgenital plate of fused sternites VIII–IX; setae given for VIII represent those anteriorly located on region of segment VIII; remainder of plate setae not quantified; genitalia of characteristic shape ( Fig. 9 ), with spinous sac having distinctively shaped associated sclerite ( Figs. 4 , 8 ).

Sexual dimorphism limited to males having smaller dimensions, often sparser abdominal chaetotaxy, and differences associated with posterior abdomen. Both sexes with similar pattern of postspiracular setal lengths. The above-listed characters will not be repeated in the species descriptions.

Figures

FIGURES 1 – 4. Myrsidea whitemani. 1. Female dorsoventral metathorax and abdomen. 2. Female hypopharyngeal sclerites. 3. Male dorsoventral metathorax and abdomen. 4. Male genital sac sclerite.

FIGURES 5 – 11. 5 – 9. Myrsidea bessae. 5. Female dorsoventral metathorax and abdomen. 6. Female hypopharyngeal sclerites. 7. Male dorsoventral metathorax and abdomen. 8. Male genital sac sclerite. 9. Male genitalia. 10 – 11. M. troglodyti, third instar nymph. 10. Dorsoventral metathorax and abdomen. 11. Hypopharyngeal sclerites.