Aporisticeras Gustafsson & Bush, 2017

Bush, Sarah E., 2017, Morphological revision of the hyperdiverse Brueelia - complex (Insecta: Phthiraptera: Ischnocera: Philopteridae) with new taxa, checklists and generic key, Zootaxa 4313 (1), pp. 1-443 : 314-315

Aporisticeras Gustafsson & Bush , new genus

Brueelia Kéler, 1936a: 257 (in partim).

Type species. Brueelia athertona Williams, 1981

Diagnosis. Aporisticeras n. gen. is most similar to Couala n. gen., but both genera are very distinct, and similarities may be superficial. No representative of Aporisticeras was included in the phylogeny of Bush et al. (2016), and its position within the Brueelia- complex is unknown.

Aporisticeras ( Fig. 526 ) and Couala ( Figs 514 , 520 ) share the following head characters: dorsal preantennal suture absent; ventral carinae continuous with marginal carina; marginal carina displaced at osculum; pns present, microsetae; preocular nodi prominent; mandibular adductor muscles prominent. In addition, while the proximal mesosome does not appear to be fused to the basal apodeme in Aporisticeras ( Figs 527–528 ) as it is in Couala ( Figs 515–516 , 521–522 ), the structure is very similar between the two genera, especially between Aporisticeras and Couala dodekopter n. sp. ( Figs 515–516 ), as is the fact that the mesosomal lobes are not very prominent, much wider than long, and both have gonopores that are similar in size relative to the mesosome. However, there are differences in the abdominal chaetotaxy ( Table 2), and head chaetotaxy, with as3 present in Aporisticeras ( Fig. 526 ), but absent in Couala ( Figs 514 , 520 ). Antennal canals are absent in Aportisticeras ( Fig. 526 ), but present in Couala ( Figs 514 , 520 ), and while the mst2 is modified in Couala , it is not in Aportisticeras. The female subgenital plate in Aporisticeras ( Fig. 531 ) forms a broad cross-piece at the vulval margin, but no such cross-piece is present in Couala ( Figs 517 , 523 ); however, in both genera the vss are microsetae, and not thorn-like. Many of the characters of the male genitalia of Aporisticeras ( Figs 527–530 ) are unique within the Brueelia -complex, and these characters separate Aporisticeras from all other genera treated here: parameres wrinkled with diaphanous median margins ( Fig. 530 ); ventral transversal sclerite connected to anterior portion of main mesosome ( Fig. 528 ); small hole penetrating dorsal surface of mesosome dorsal to gonopore; 3 pst present on each paramere, two sensilla and one terminal microseta.

Description. Both sexes. Head broad, rounded triangular ( Fig. 526 ). Marginal carina uninterrupted; displaced dorsally and posteriorly at osculum. Dorsal preantennal suture absent. Ventral anterior plate absent. Ventral carinae continuous with marginal carina. Head setae as in Fig. 526 . Coni small. Antennae monomorphic. Temporal carinae not visible; mts 3 only macrosetae. Gular plate pentagonal, with prominent median point.

Prothorax ( Figs 524–525 ) rectangular. ppss on posteto-lateral corners. Proepimera slender; median ends blunt or hook-shaped. Pterothorax trapezoidal; lateral margins divergent; posterior margin flat or slightly rounded; mms widely separated medianly. Meso- and metasterna fused; 2 setae on each side. Metepisterna moderate; median ends blunt. Leg chaetotaxy as in Fig. 25 , except fI-p2, fI-v4, fII-v2, fIII-v2, absent.

Abdomen oblong ( Figs 524–525 ). Abdominal chaetotaxy as in Table 2 and Figs 524–525 . Tergopleurites rectangular; tergopleurites II–IX+X in male and tergopleurites II–VIII in female moderately separated medianly; tergopleurites IX+X and XI fused in female. Sternal plates rectangular, do not approach pleurites. Pleural incrassations large. Ventral section of tergo-pleurites broad. Re-entrant heads slight, broad. Male subgenital plate roughly rectangular, lateral margins irregular, reaching posterior margin of abdomen. Female subgenital plate oval, reaching vulval margin where it flares into broad cross-piece ( Fig. 531 ). Vulval margin with slender vms, thorn-like vss; vos follow lateral margins of subgenital plate, not approaching vss ( Fig. 531 ).

Basal apodeme ( Fig. 527 ) rounded rectangular. Proximal mesosome small, convex. Anterior transverse sclerite (ATS in Fig. 528 ) across proximal mesosome unique in Brueelia -complex. Gonopore ( Fig. 528 ) prominent, terminal, margins not thickened, open distally. Mesosomal lobes wide, overlapping parameres. Distal transverse sclerite (DTS in Fig. 528 ) just posterior and dorsal to gonopore unique in Brueelia -complex; ames absent; 2 pmes microsetae on lateral margins of mesosomal lobes. Parameral heads ( Figs 529–530 ) blunt, with distinct grove into which the lateral ends of mesosomal lobes fit. Parameral blades convergent, median margin diaphanous in proximal section, lateral margin with ventral wrinkles; 3 pst per paramere, 2 as central sensilla and 1 as a terminal microseta.

Host distribution. Aporisticeras is monotypic, known only from two species of bee-eaters in the genus Nyctyornis Jardine & Selby, 1830 .

Geographical range. South and Southeast Asia.

Etymology. Aporisticeras is formed by the Greek prefix “ aporeía ” for “puzzlement, confusion”, referring to the general structure of the male genitalia ( Fig. 527 ), which are very different from those of other members of the Brueelia -complex and difficult to interpret, together with the Greek suffixes “ istío ” for “sail” and “ kérato ” for horn, referring to the sail-shaped parameres ( Figs 529–530 ). Gender: masculine.

Included species

* Aporisticeras athertona ( Williams, 1981: 517) n. comb. [in Brueelia ]

Figures

FIGURES 25. Dorso-ventral views of coxae I – III, trochanters I – III, and femora I – III, showing terminology of the leg setae used here. Other parts of the thorax removed for clarity. Setae situated marginally are illustrated and named on both dorsal (lefthand) and ventral (right-hand) sides. Terminology for individual seta as used in the text obtained by combining the leg segment (larger font) and the setal name (smaller font). Abbreviations: a 1 – 5, anterior setae 1 – 5; cI – III, coxae I – III; d 1 – 3, dorsal setae 1 – 3; dm 1 – 4, distal marginal setae 1 – 4; fI – III, femur I – III; p 1 – 3, posterior setae 1 – 3; s 1 – 6, sensilla 1 – 6; tI – III, trochanter I – III; v 1 – 4, ventral setae 1 – 4.

FIGURES 526 – 531. Aporisticeras athertona (Williams, 1981) n. comb. ex Nyctyornis athertoni athertoni: 526, male head, dorsal and ventral views. 527, male genitalia, dorsal view. 528, male mesosome, ventral view. 529, male paramere, dorsal view. 530, male paramere, ventral view. 531. female subgenital plate and vulval margin, ventral view. Abbreviations: ATS, anterior transverse sclerite; DTS, distal transverse sclerite.

FIGURES 514 – 517. Couala dodekopter n. gen. & n. sp. ex Coua cristata pyropyga: 514, male head, dorsal and ventral views. 515, male genitalia, dorsal view. 516, distal male genitalia, ventral view. 517, female subgenital plate and vulval margin, ventral view.

FIGURES 520 – 523 Couala angulata (Piaget, 1880) n. comb. ex Coua caerulea: 520, male head, dorsal and ventral views. 521, male genitalia, dorsal view. 522, male mesosome and parameres, ventral view. 523, female subgenital plate and vulval margin, ventral view.

FIGURES 524 – 525. Aporisticeras athertona (Williams, 1981) n. comb. ex Nyctyornis athertoni athertoni: 524, male habitus, dorsal and ventral views. 525, female habitus, dorsal and ventral views.