Schizosairhynchus erysichthoni Gustafsson & Bush

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: 279-282

publication ID

https://doi.org/10.11646/zootaxa.4313.1.1

publication LSID

lsid:zoobank.org:pub:A5Fdfba5-F992-44A8-84C2-1756C943C19B

persistent identifier

http://treatment.plazi.org/id/832187E9-FE9C-FEDA-FF74-6298FB62FC9B

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Plazi

scientific name

Schizosairhynchus erysichthoni Gustafsson & Bush
status

new species

Schizosairhynchus erysichthoni Gustafsson & Bush  , new species

( Figs 463–469View FIGURES 463 – 464View FIGURES 465 – 469)

Type host. Aplonis metallica metallica (Temminck, 1824)  —metallic starling. Type locality. Morobe District, Papua New Guinea.

Other host. Aplonis metallica nitida (Grey, 1858)  —metallic starling.

Diagnosis. Male Schizosairhynchus erysichthoni  n. sp. is separated from the other two species in the genus by the following characters: distal mesosome relatively slender in Sc. erysichthoni  ( Fig. 467View FIGURES 465 – 469), but much wider in Sc. minovenator  n. sp. ( Fig. 474View FIGURES 472 – 476) and Sc. philippensis  (the distal mesosome of undescribed species of Schizosairhynchus  n. gen. on Aplonis  spp. are similar to that of Sc. erysichthoni  ; unpub. data); ventral sclerite does not extend distal to gonopore in Sc. erysichthoni  ( Fig. 467View FIGURES 465 – 469) but does extend lateral and distal to gonopore in the other two species ( Fig. 474View FIGURES 472 – 476); rugose nodi small, oblong in Sc. erysichthoni  ( Fig. 467View FIGURES 465 – 469) but larger and rounded in the other two species ( Fig. 474View FIGURES 472 – 476); pmes situated antero-lateral to rugose nodi in Sc. minovenator  ( Fig. 474View FIGURES 472 – 476) and Sc. philippensis  , but postero-lateral to nodi in Sc. erysichthoni  (fig. 467); thickening of anterior margin of proximal mesosome transversally continuous in Sc. minovenator  ( Fig. 474View FIGURES 472 – 476) and Sc. philippensis  but only lateral in Sc. erysichthoni  ( Fig. 467View FIGURES 465 – 469). Note that in the original description of Sc. philippensis  ( Tandan & Kumar 1969: fig. 7), neither the ventral sclerite, the rugose nodi, the pmes, or the anterior thickening of the proximal mesosome is illustrated. Yet, even in this illustration, the shape of the mesosome and the presence of the small paired nodi just distal to the gonopore separates this species from Sc. erysichthoni  .

Female Schizosairhynchus erysichthoni  separated from the other two species in the genus by the partial crosspiece of the subgenital plate ( Fig. 469View FIGURES 465 – 469); no such cross-piece exists in Sc. minovenator  ( Fig. 476View FIGURES 472 – 476), and in Sc. philippensis  the subgenital plate not reach the vulval margin. Both Sc. minovenator  ( Fig. 476View FIGURES 472 – 476) and Sc. philippensis  have more than 22 vss on each side, whereas Sc. erysichthoni  ( Fig. 469View FIGURES 465 – 469) only has 12–16.

Description. Both sexes. Head shape, structure, and chaetotaxy as in genus description and Fig. 465View FIGURES 465 – 469. Lateral margins of dorsal anterior plate shallowly convex. Thoracic and abdominal segments as in genus description and Figs 463–464View FIGURES 463 – 464. Tergopleural and sternal plates light brown; antero-lateral corners of tergopleurites and pleurites darker.

Male. Abdominal chaetotaxy as in Table 2 and Fig. 463View FIGURES 463 – 464. Sternal plates IV –VI and subgenital plate with small accessory plates laterally ( Fig. 463View FIGURES 463 – 464); 2 accessory plates lateral to subgenital plate on each side. Basal apodeme ( Fig. 466View FIGURES 465 – 469) rounded rectangular to trapezoidal. Proximal mesosome quadratic, anterior margin flat to slightly concave, with distinct thickenings laterally. Gonopore ( Fig. 467View FIGURES 465 – 469) ventral, narrowly open distally, with pair of slender sclerites attached to anterior margin. Mesosomal lobes wide, fused distally, with distal margin thickened. Rugose nodi slight, flattened. Ventral sclerite (VS in Fig. 467View FIGURES 465 – 469) does not extend distal to gonopore; sclerite not thickened anteriorly; 2 ames microsetae on each side of ventral sclerite; 2 pmes microsetae on each side, postero-lateral to rugose nodi. Parameral heads ( Fig. 468View FIGURES 465 – 469) roughly triangular. Parameral blades gently curved, somewhat irregular, tapering slowly, not extended distally; pst1–2 as in genus description. Measurements ex Aplonis metallica metallica  (n = 15): TL = 1.25–1.37 (1.31); HL = 0.45–0.51 (0.47); HW = 0.45–0.49 (0.46); PRW = 0.26–0.30 (0.28); PTW = 0.39–0.44 (0.41); AW = 0.54–0.68 (0.61). Ex A. m. nitida  (n = 5 except n = 4 for AW, TL): TL = 1.31–1.38; HL = 0.45–0.49; HW = 0.45–0.49; PRW = 0.27–0.31; PTW = 0.40–0.44; AW = 0.59–0.67.

Female. Abdominal chaetotaxy as in Table 2 and Fig. 464View FIGURES 463 – 464. Sternal plates wide ( Fig. 464View FIGURES 463 – 464); sternal plates III –VI and subgenital plate with small accessory plates laterally. Subgenital plate roughly triangular, but anterior margin convex ( Fig. 469View FIGURES 465 – 469); distally subgenital plate reaches vulval margin and expands into partial cross-piece. Vulval margin ( Fig. 469View FIGURES 465 – 469) bulging slightly medianly, with 5–7 long, slender vms on each side, and 12–16 short, thorn-like vss on each side; 7–8 short, slender vos; proximal 4–5 vos scattered on subgenital plate, and distal 3 vos approaching vss. Measurements ex Aplonis metallica metallica  (n = 17 except n = 16 for HW and n = 15 for AW): TL = 1.49–1.74 (1.58); HL = 0.48–0.55 (0.51); HW = 0.47–0.54 (0.50); PRW = 0.29–0.34 (0.31); PTW = 0.39– 0.49 (0.45); AW = 0.62–0.82 (0.70). Ex A. m. nitida  (n = 6 except n = 4 for AW and n = 3 for TL): TL = 1.54–1.62; HL = 0.47–0.52; HW = 0.47–0.52; PRW = 0.29–0.32; PTW = 0.43–0.47; AW = 0.68–0.72.

Etymology. The species epithet is in honour of Erysichthon, the king of Thessaly who, after cutting down a sacred grove of trees devoted to Demeter, the goddess of harvests, was cursed to have Limos, the goddess of starvation, placed in his stomach. This drove him to insatiable hunger, and he eventually ate himself. While we do not suggest that this regularly happens to Schizosairhynchus erysichthoni  (for the days of the Old Gods seem to be over), it is a fitting name for a louse species that is prepared to eat a “metallic” starling.

Type material. Ex Aplonis metallica metallica  : Holotype ♂, 12 miles NE of Lae, elev. 100 ft, Silium Village, Bupu River, Morobe District, Papua New Guinea, 20 Apr. 1970, A.B. Mirza, BBM-NG-98658 ( BPBM)  . Paratypes: 3♂, 5♀, same data as holotype ( BPBM)  ; 1♂, 1♀, same data as holotype, except BBM-NG-98656 ( BPBM)  ; 1♀, 20 km N of Bulolo, elev. 1900 ft, Sum Sum , Morobe District, Papua New Guinea, 11 Feb. 1963, H. Clissold, BBM-NG-21215 ( BPBM)  ; 1♀, Sindeada , elev. 10 m, Milne Bay District, Papua New Guinea, 1 Apr. 1965, P.J. Shanahan, BBM-NG-24532 ( BPBM)  ; 1♀, Jumbora Plantation , elev. 25 m, Popondetta, Northern District, Papua New Guinea, BBM-NG-24925 ( BPBM)  ; 5♂, 8♀, Popondetta , elev. 200 m, Northern District, Papua New Guinea, 4 Sep. 1963, P.J. Shanahan, BBM-NG-28698, 28700, 28705, 28707 ( BPBM)  ; 2♂, Popondetta , elev. 60 m, Northern District, Papua New Guinea, 7 Sep. 1963, P.J. Shanahan, BBM-NG-28706 ( BPBM)  ; 3♂, 3♀, Soputa River , elev. 200 ft, Northern District, Papua New Guinea, 28–29 Sep. 1963, H. Clissold, BBM-NG-29718, 29850 ( BPBM)  ; 1♂, 2♀, same locality and collector as previous, 4–5 Oct. 1963, BBM-NG-29838 ( BPBM)  ; 3♂, 8♀, Zenani , elev. 400 ft, Northern District, Papua New Guinea, 11 Oct. 1963, H. Clissold, BBM-NG-29946–7, 29950–1, 29954–5 ( BPBM)  ; 2♂, Ahola , elev. 150 ft, Northern District, Papua New Guinea, 7 Oct. 1963, H. Clissold, BBM-NG-29879, 29949 ( BPBM)  ; 2♂, 1♀, Cape Killerton , elev. 10 ft, Northern District, Papua New Guinea, 20 Oct. 1963, H. Clissold, BBM-NG-29728 ( BPBM)  ; 2♂, Ambunti , elev. 200 ft, West Sepik District, Papua New Guinea, 7 May 1963, P. Temple, BBM-NG-22563, BBM-NG-22565 ( BPBM)  .

Ex Aplonis metallica nitida  : 3♂, 4♀, Broala , elev. 20 m, Santa Isabel Island, Solomon Islands, 24 Aug. 1964, P.J. Shanahan, BBM-SI-24282, 24210 ( BPBM)  ; 2♂, 3♀, elev. 20 m, Malaita Island, Solomon Islands, 29 Jun. 1964, P.J. Shanahan, BBM-NG-24074 ( BPBM)  .

Remarks. We found few differences between specimens from the two host subspecies. Material from A. metallica nitida  from Malaita Island is generally darker than that from other localities, and there are fewer vss (12– 14 compared to 13–16 in material from A. metallica metallica  ). Many females from A. m. nitida  have 6 mediansubmedian pairs of macrosetae on tergopleurites III –IV instead of the 5 pairs in material from A. m. metallica  . Amore thorough study of the Schizosairhynchus  from Aplonis  starlings is needed to determine the significance of these differences. Conservatively, we treat material from both host subspecies as one species.