Apomyrsidea, Kolencik & Sychra & Allen, 2021

Kolencik, Stanislav, Sychra, Oldřich & Allen, Julie M., 2021, Another puzzle piece in the systematics of the chewing louse genus Myrsidea, with a description of a new genus Apomyrsidea, European Journal of Taxonomy 748, pp. 36-50 : 39-43

Genus Apomyrsidea gen. nov.

urn:lsid:zoobank.org:act:5A86DF15-251D-4262-9BDF-92A3E1BE9C6C

Myrsidea Waterston, 1915: 12 (in partim).

Type species

Apomyrsidea klimesi (Sychra in Sychra et al., 2006: 55) gen. et comb. nov.

Diagnosis

Apomyrsidea can be characterized and distinguished from all other menoponid chewing lice genera with the combination of following characteristics:

Head

- rounded anteriorly, lacking lateral slit or notch, without sclerotized processes (oral spines) arising near the base of maxillary palpi ( Figs 1–3 );

- alveoli of dorsal head setae (dhs; marginal temporal setae by Clay 1969) 26 and 27 not closely associated ( Fig. 3 );

- dhs 18 (outer mid-dorsal head seta by Clay (1966) or dorsal head seta „d“ by Clay (1962) is missing;

- dhs 22 (outer occipital seta by Valim & Weckstein 2013 or posterior dorsal head seta „f“ by Clay 1962) approximately as long as dhs 21 (inner occipital seta by Valim & Weckstein 2013), both surpassing pronotal carina;

- dhs 23 (posterior dorsal head seta “e” in Clay 1962) present and anteriorly to line of bases of dhs 21 and 22 ( Fig. 3 );

- head sensilla 3–5 sensu Clay (1961) or c–e sensu Clay (1969) absent;

- characteristic gular plate with the greater length and thickness of the posterior pair of setae compared to the rest ones ( Figs 1–2 ).

Thorax

- prosternal plate well developed with straight anterior margin and two anterior setae ( Fig. 4 );

- pronotum with one pair of minute dorso-central pronotal setae lying near the transverse carina (dps 2 by Clay 1962) ( Fig. 3 );

- pronotum with anterolateral pronotal setae (marginal prothoracic setae 1–3, mps 1–3 in Clay 1962) in following arrangement: mps 1 and mps 3 spine-like, mps 2 fine and long; mps 1 and mps 2 located on each lateral corner of pronotum, with mps 3 posteriorly to mps 2 on pronotal margin ( Fig. 3 );

- mesonotum well defined with only two anterior setae;

- mesonotum without median division, but with a Y-shaped line just below postnotum, not forming a suture or even splitting mesonotum ( Fig. 3 ). This Y-shaped line slightly less evident, but also discernible in good specimens from other host families;

- strongly sclerotized ring-like mesothorax – mesothorax with sternum, pleura and tergum fused to form strongly sclerotized ring round the body;

- femur III without combs of spine-like setae but with thick or sparse brushes of setae.

Abdomen

- sternite I mostly surrounded by sternite II (it lies inside the wide notch of sternite II) ( Fig. 5 );

- sternite II enlarged with a clutch of heavy spine-like setae at each posterior-lateral margin called aster;

- male genitalia as in Fig. 6 .

- male genital sac sclerite with two roughly serrated spiculated lateral arms ( Figs 7–9 );

- female vulva with smooth posterior margin ( Fig. 1 );

- female ventral anal margin without lateral seta-bearing processes (see Clay 1969);

- sternite VII fused with VIII + IX+ X, forming female subgenital plate, although with a distinct transverse fenestra distinctly enclosed at lateral sides of subgenital plate where seventh and eighth segments fused (in A. circumsternata and A. isacantha ; see Valim & Weckstein 2013: fig. 11); in the case of A. klimesi – male abdominal sternite VIII and female sternite VII both separated from the subgenital plate, which is formed by a single sternite IX (in the male) or fusion of sternites VIII and IX (in the female) ( Figs 1–2 ).

Etymology

The generic name Apomyrsidea is formed by a combination of Greek word ‘ Apo ’ = ‘from’ and Myrsidea , referring that it is separated from the genus Myrsidea , where it was originally placed. The gender is feminine.

Included species

Three species are included in the Apomyrsidea gen. nov., all are restricted to formicariid hosts:

Apomyrsidea circumsternata ( Valim & Weckstein, 2013) gen. et comb. nov.

Apomyrsidea isacantha ( Valim & Weckstein, 2013) gen. et comb. nov.

Apomyrsidea klimesi (Sychra in Sychra et al., 2006) gen. et comb. nov.

Descriptions of all three species are well presented in the original papers ( Sychra et al. 2006; Valim & Weckstein 2013). Valim & Weckstein (2013) also presented a key to their identification.

Figures

Figs 1–2. Dorso-ventral view of Apomyrsidea klimesi (Sychra in Sychra et al., 2006) gen. et comb. nov. (CR15). 1. ♀. 2. ♂.

Figs 3–9. 3–6. Apomyrsidea klimesi (Sychra in Sychra et al., 2006) gen. et comb. nov. (CR15). 3. Dorsal view of head, prothorax and mesothorax of female. 4. Prosternal plate of female. 5. Metasternal plate and sternites I–III of female. 6. Male genitalia. – 7–9. Male genital sac sclerites. 7. A. klimesi gen. et comb. nov. 8. A. circumsternata (Valim & Weckstein, 2013) gen. et comb. nov. 9. A. isacantha (Valim & Weckstein, 2013) gen. et comb. nov. Abbreviations: a–b = head sensilla; dps = dorso-central pronotal setae; mps = marginal prothoracic setae; 8–30 = dorsal head setae. Figs 7–9 are drawn to the same scale.