The Goniodidae (Phthiraptera: Ischnocera) of peafowl (Aves: Galliformes: Pavo), with description of a new genus Author Gustafsson, Daniel R. Author Grossi, Alexandra A. Author Ren, Mengjiao Author Zou, Fasheng text Journal of Natural History 2023 2023-07-14 57 17 - 20 996 1048 http://dx.doi.org/10.1080/00222933.2023.2226375 journal article 264215 10.1080/00222933.2023.2226375 79c6cc16-cda1-4ea6-9ffb-05855d9cbfcf 1464-5262 8270799 FFDF1435-92D6-4C19-9B51-3AB61E1BD7DA Goniodes pavonis ( Linnaeus, 1758 ) Pediculus pavoni Linnaeus, 1758: 613 [misprint for pavonis ; see von Kéler 1940: 39 ]. Ricinus pavonis Linnaeus [1758] ; Latreille 1802: 389 . Nirmus tetragonocephalus Olfers, 1816: 90 [unnecessary replacement name for P. pavonis ]. Goniodes falcicornis Nitzsch, 1818: 293 [unnecessary replacement name for P. pavonis ]. ̍ Nirmus pavonis Herm ̾.; Kirby and Spence 1823: 321 . Goniodes ( Philopedon ) falcicornis (Nitzsch) ; Stephens 1829: 333 . Goniodes falcicornis Nitzsch ,in Burmeister 1838 ; Harrison 1916: 76 [as synonym of G. pavonis ] Goniodes pavonis Linné, 1758, 1916: 78 . Goniodes tetragonocephalus Olfers, 1816, 1916: 79 [as synonym of G. pavonis ]. ( Figures 1–9 ) Type host Pavo cristatus Linnaeus, 1758 – Indian peafowl. Neotype locality India ( Clay 1940 , p. 7). Other hosts Pavo muticus imperator Delacour, 1949 (Ref: Emerson and Elbel 1957 ). Description Both sexes. Head broader than long ( Figure 3 ), frons gently rounded to somewhat flattened medianly. Marginal carina uninterrupted, but slightly indented laterally at site of as1 and as2 . Preantennal nodi elongated. Coni strongly curved posteriorly. Antennae sexually dimorphic. Head chaetotaxy as in Figure 3 ; as1–3, avs1 and pcs clearly ventral; os sexually dimorphic. Temples rounded, but extended posteriorly at site of mts4–5 , more distinct in male than in female. Temporal carinae clearly visible. Prothorax with anterior margin indented ( Figures 1–2 ); rhombic sclerite not fused to pronotum, with posterior margin indented. Postero-lateral corner of pronotum with single ppss on each side. Proepimera not fused medianly, mesofurcal pit lateral. Mesosternal plate present, oval. Sternal setae present on both meso- and metathorax. Postero-lateral corner of pteronotum modified so that ipts are more or less posterior to lpts . Small sensillum associated with smns; mpts absent. Posterior margin of pteronotum separate from tergopleurite II in both sexes, median end gently rounded. Abdominal plates and chaetotaxy as in Figures 1–2 ; tergopleurites II–VIII extended medianly. Intertergal plates absent. Accessory lateral sternal plates present on segments II–VI as elongated, oblique ovals; central sternal plates absent. Tergopleurites IX–XI sexually dimorphic. Measurements as in Table 1 . Figure 2. Goniodes pavonis ( Linnaeus, 1758 ) , female habitus, dorsal and ventral views. Figures 3–7. Goniodes pavonis ( Linnaeus, 1758 ) . 3 , male head, dorsal and ventral views. 4 , female antenna and conus, ventral view. 5 , male genitalia, dorsal view. 6 , male genitalia, ventral view. 7 , female genitalia and abdominal segments VII–XI, ventral view. Figures 8–9. Goniodes pavonis ( Linnaeus, 1758 ) . 8 , male abdominal segments IX–XI, dorsal view, showing the inner margin of the ano-genital opening; grey line indicates the approximate outline of the central dorsal plate of abdominal segment IX+X. 9 , male abdominal segments IX–XI, dorsal and ventral views, showing the outer surface. Plates and setae shown in Figure 8 are located underneath the central plate of segment IX+X. Table 1. Measurements (in millimetres) of the species treated here. Abbreviations: TL = total length (along midline); HL = head length (along midline); HW = head width (at temples); PRW = prothoracic width; PTW = pterothoracic width; AW = abdominal width (at segment V, for consistency, AW is measured at segment V even in Pavoniocotes , but the abdomen is wider at the posterior end of segment IV in some specimens of this genus). One specimen of Pavoniocotes parviceps ( Piaget, 1880 ) which appears to be either a tenereal male or an exuvium is not measured.

Louse species	Host species	Sex	N	TL	HL	HW	PRW	PTW	AW
Goniocotes	Pavo cristatus	M	1	1.04	0.35	0.41	0.25	0.38	0.54
rectangulatus	Linnaeus, 1758
(Nitzsch [in
Giebel] 1866)
F	1	1.34	0.42	0.51	0.26	0.43	0.65
Goniodes	Pavo cristatus	M a	2	3.69	0.83–0.86	1.04–1.09	0.81–0.90	1.15–1.29	1.94
meinertzhageni	Linnaeus, 1758
( Clay, 1940 )
F	1	3.62	0.94	1.34	0.83	1.18	1.85
Goniodes pavonis	Pavo cristatus	M	7	2.86–3.87	0.91–0.98	1.12–1.15	0.83–0.91	1.19–1.23	2.09–2.19
( Linnaeus, 1758 )	Linnaeus, 1758
F	6	3.80–4.15	0.98–1.07	1.33–1.42	0.83–0.92	1.22–1.27	2.04–2.34
Pavoniocotes mayuri	Pavo cristatus	M	1	2.37	0.55	0.62	0.49	0.78	1.24
(Lakshminarayana	Linnaeus, 1758
and Emerson,
1971)
F	4	1.78–2.10	0.49–0.55	0.67–0.81	0.44–0.53	0.63–0.76	0.97–1.14
Pavoniocotes	Pavo cristatus	M	6	1.87–2.16	0.46–0.49	0.44–0.51	0.50–0.60	0.68–0.81	1.07–1.25
parviceps	Linnaeus, 1758
( Piaget, 1880 )
F	4	1.95–2.04	0.53–0.57	0.74–0.81	0.46–0.54	0.75–0.78	1.06–1.16
Pavo muticus	M	6	1.98–2.23	0.47–0.51	0.48–0.51	0.52–0.61	0.75–0.84	1.10–1.29
Linnaeus, 1766
F b	10	1.96–2.17	0.51–0.57	0.69–0.81	0.47–0.53	0.67–0.78	1.05–1.18
(0.54)	(0.75)	(0.50)	(0.72)	(1.11)

a N = 1 for TL and AW. b N = 9 for TL. Male. Conus bent strongly posteriorly. Antennae modified ( Figure 3 ): scape very swollen and elongated, with single squamous thumb-like process and thickened seta on posterior margin; pedicel slightly curved with slight bulge on posterior margin in distal end; distal flagellomere I extended posteriorly, posterior margin rugose; flagellomeres II–III more or less as in female. Post-antennal head with 10–13 sensilla on each side in curved band anterior to temporal carinae; s1–2 present most posteriorly and s6 present anterior to preantennal nodi. Many dorsal head setae slightly longer in male than in female, most conspicuously the os . Temple margin more sinuous and posterior extension at mts4–5 more distinct in male. Tergopleurites II–VIII with most or all tps microsetae; only tps situated median to tergopleurites macrosetae. Abdominal segments IX–XI highly modified: tergopleurite IX small, roughly circular; medianly continuous tergopleurite X extended antero-laterally to tergopleurite IX to reach near tergopleurite VIII ( Figure 9 ). Genital opening hidden underneath posterior end of tergopleurite X, with small sclerite (tergopleurite XI?) present just posterior to genital opening ( Figure 8 ). Genital opening with row of microsetae distinct from row across tergopleurite X. Subgenital plate as in Figure 9 . Male genitalia as in Figures 5–6 . Basal apodeme shorter than more distal elements, widening distally, with central Y-shaped thickening on ventral side. Mesosome somewhat asymmetrical dorsally; elongated and deeply divided in distal end. Antero-lateral margins extended laterally into hook-shaped dorsal structures that interlock with parameral heads. Ventral mesosome with thickened anterior margin, paired distal sclerotised extensions, and more hyaline lateral lobes at around mid-length. In anterior end a U-shaped sclerite with rugose lateral margins. Parameres widened distally, blunt, with pst1–2 as microsetae on distal margin. Female. Coni bent posteriorly, but not as distinct as in male ( Figure 4 ). Female antennae stout, but not modified ( Figure 4 ). Post-antennal head with only s2 and 2 more central sensilla visible on each side; most head setae shorter than male. Temple margin more straight and with less prominent extension at mts4–5 . Tergopleurites II–VI with all or most tps macrosetae; tergopleurites VII–VIII with numerous tps microsetae on each side. Tergopleurites IX–XI fused, medianly continuous, with posterior margins indented sublaterally. Subgenital plate absent ( Figure 7 ). Internal sclerite of genitalia elongated, present on one side only. Vulval margin concave, with chaetotaxy as in Figure 7 . Subvulval plates present as small, oval plates near terminal margin of abdomen. Material examined Neoparatypes. 2♂, 4♀ , India (Zoo), 1937, leg . R . Meinertzhagen, 8321, NHMUK010676937 ( NHML ) . 3♂, India (Zoo), Jan. 1938 , leg. R . Meinertzhagen, 11,135, NHMUK010676956 ( NHML ) . Non-types: 2♂, 2♀ , no locality, 3 September 1967 , leg. R . S. Balter , Brit . Mus . 1967–599, NHMUK010676934–5 ( NHML ) . Remarks Clay (1940 , p. 5) considered G. pavonis to be connected to her species group B through Goniodes meinertzhageni Clay, 1940 (see below). However, group B is itself not morphologically homogeneous, and comprises three different species groups. Structures such as male and female genitalia, head shape, structure of the scape, head chaeto- and sensillotaxy, and abdominal chaetotaxy suggest that species groups A and B sensu Clay (1940) comprise four different groups, though the relationships between these are difficult to assess. No other species of Goniodes is similar to G. pavonis .