Guimaraesiella (Cicchinella) retusa Gustafsson, Clayton

Gustafsson, Daniel R., Clayton, Dale H. & Bush, Sarah E., 2019, Twelve new species of Guimaraesiella (Phthiraptera: Ischnocera: Philopteridae) from “ babblers ” (Passeriformes: Leiothrichidae, Pellorneidae, Timaliidae) with a description of a new subgenus and a key to its species, Zootaxa 4543 (4), pp. 451-497 : 458

Guimaraesiella (Cicchinella) retusa Gustafsson, Clayton & Bush, new species

( Figs 8–14 )

Type host. Trochalopteron milnei sinianum Stresemann, 1930 —red-tailed laughing-thrush ( Leiothrichidae ).

Type locality: Jingxin County, Guangxi Province , China .

Diagnosis. Guimaraesiella (C.) retusa is most similar to Guimaraesiella (C.) philiproundi n. sp., with which is shares the following characters: (1) female subgenital plate reticulated ( Figs 14 , 22 ); (2) anterior margin of TN broadly flattened ( Figs 12 , 20 ); and (3) mesosomal ventral sclerite without an anterior rugose area ( Figs 12 , 20 ). However, these two species can be separated by the following characters: (1) lateral margins of preantennal head straight to slightly concave in G. (C.) retusa ( Fig. 10 ) but convex in G. (C.) philiproundi ( Fig. 17 ); (2) antennae sexually dimorphic in G. (C.) philiproundi ( Figs 17–18 ) but not in G. (C.) retusa ( Fig. 10 ); (3) mesosomal ventral sclerite broad in G. (C.) retusa ( Fig. 12 ) but narrow in G. (C.) philiproundi ( Fig. 20 ); (4) lateral margins of mesosome more sinuous in G. (C.) retusa ( Fig. 12 ) than in G. (C.) philiproundi ( Fig. 20 ); (5) ames microsetae in G. (C.) retusa ( Fig. 12 ) but sensilla in G. (C.) philiproundi ( Fig. 20 ); and (6) reticulation of female subgenital plate more pronounced in G. (C.) philiproundi ( Fig. 22 ) than in G. (C.) retusa ( Fig. 14 ).

Description. Both sexes. Head pentagonal ( Fig. 10 ). Lateral margins of preantennal area straight to slightly concave. Dorsal preantennal suture reaches lateral margins of head, but does not completely separate dorsal anterior plate from mean head plate. Head chaetotaxy as in Fig. 10 ; pns sensilla. Coni short, not reaching distal margin of scapes. Antennae not sexually dimorphic. Gular plate triangular. Thoracic and abdominal segments as in Figs 8–9 . Reentrant heads of pleurites broad and long.

Male. Thoracic and abdominal chaetotaxy as in Fig. 8 . Male genitalia as in Figs 11–13 . Basal apodeme broad ( Fig. 11 ), roughly rectangular. Proximal mesosome rectangular ( Fig. 12 ), with sinuous lateral margins. Mesosomal lobes also with sinuous lateral margins. Marginal thickening of lobes not displaced medianly in anterior end. Large trapezoidal nodi with flat anterior margins on distal mesosome. Gonopore open distally, shapes as in Fig. 12 ; 2 ames microsetae on each side near antero-lateral corners of mesosomal lobes; gpmes not visible in examined material; 2 lpmes microsetae on each side in concave section of lateral margins of mesosome. Parameral heads irregular ( Fig. 13 ). Parameral blades slightly elongated, tapering only distally; pst1–2 close together. Measurements (n = 1): TL = 1.15; HL = 0.32; HW = 0.33; PRW = 0.19; PTW = 0.30; AW = 0.42.

Female. Thoracic and abdominal chaetotaxy as in Fig. 9 ; ss of tergopleurite VIII much shorter than ss of tergopleurites II–VII, not visible in all examined females. Subgenital plate ( Fig. 14 ) with central reticulation; crosspiece broad, with very broad connection to subgenital plate. Vulval margin rounded ( Fig. 14 ), with 3 slender vms and 7–8 short, thorn-like vss on each side (one specimen with 12 on one side); 3–4 long, slender vos on each side; distal vos median to vss. Measurements (n = 3): TL = 1.51–1.54; HL = 0.36–0.38; HW = 0.37–0.38; PRW = 0.22– 0.23; PTW = 0.33–0.35; AW = 0.50–0.52.

Etymology. The species epithet is derived from “ retusa ”, Latin for “blunt”, referring to the broad, blunt preantennal area.

Type material. Ex Trochalopteron milnei sinianum : Holotype Ƌ, 23.122'N, 105.963'E, Jingxin County, Guangxi Province, China, 28 Sep. 2004, S.E. Bush , Bird ATP-2004-108, Louse P-314, PIPeR # 83 (NHML). Paratypes: 3♀, same data as holotype (PIPeR).

Figures

FIGURES 8–9. Guimaraesiella (Cicchinella) retusa n. sp. 8, male, whole body, dorsal and ventral views. 9, female, whole body, dorsal and ventral views.

FIGURES 10–14. Guimaraesiella (Cicchinella) retusa n. sp. 10, male head, dorsal and ventral views. 11, male genitalia, dorsal view. 12, male mesosome, ventral view. 13, male paramere, dorsal view. 14, female subgenital plate and vulval margin, ventral view.

FIGURES 17–22. Guimaraesiella (Cicchinella) philiproundi n. sp. 17, male head, dorsal and ventral views. 18, female antenna, ventral view. 19, male genitalia, dorsal view. 20, male mesosome, ventral view. 21, male paramere, dorsal view. 22, female subgenital plate and vulval margin, ventral view.

FIGURES 1–2. Guimaraesiella (Cicchinella) sehri (Ansari, 1955). 1, male, whole body, dorsal and ventral views. 2, female, whole body, dorsal and ventral views.