Goniocotes Burmeister, 1838

Gustafsson, Daniel R., Tian, Chunpo & Zou, Fasheng, 2021, New species of ischnoceran chewing lice (Phthiraptera: Philopteridae) from Chinese birds, Zootaxa 4990 (2), pp. 305-328 : 309

Goniocotes Burmeister, 1838

Goniocotes Burmeister, 1838: 431 . Type species: Ricinus gallinae De Geer, 1778 .

Dictyocotes Kéler, 1939: 153 . Type species: “ Goniocotes haplogonus (Nitzsch) ”.

Remarks. The morphological separation of Goniocotes and Goniodes Nitzsch, 1818 has never been clearly established, and Clay (1951) suggested that these two genera would “seem to grade into each other” if sufficient species were examined. Characters that are often used to separate these genera include sexually dimorphic antennae in Goniodes , but monomorphic antennae in Goniocotes ; relatively narrow head with rounded temples in Goniocotes , but relatively wide head with angular temples in Goniodes ; simple, solenoid genitalia in Goniocotes compared to the more complex genitalia in Goniodes . (see Mjöberg 1910; Kéler 1939; Keirans 1967; Ledger 1980; Mey 1997; Price et al. 2003).

However, neither these characters, nor the combination of some or all of them, clearly separate Goniocotes from Goniodes . For example, the two species described below have wide heads with angular temples as in Goniodes (Figs 7, 10), but have sexually monomorphic antennae as in Goniocotes . The male genitalia of Goniocotes kristinae new species (Fig. 8) are simple and solenoid as in Goniocotes , whereas those of Goniocotes rolandi new species ( Figs 14–15 ) are more complex, and intermediate between those of Goniodes and those of Goniocotes . Moreover, species such as Goniocotes mayuri Lakshminarayana & Emerson, 1971 have sexually dimorphic antennae, whereas the antennae of Goniodes macrocephalus ( Taschenberg, 1882) are not appreciably dimorphic. Also, Goniodes dissimilis Denny, 1842 has male temples and genitalia that are more similar to those of Goniocotes than to those of most other Goniodes .

A thorough study of this large group of species is needed to resolve what characters may separate Goniodes and Goniocotes or if they should be merged as one genus. Alternatively, this group may have to be subdivided into several genera, resurrecting some of the many current junior synonyms (see Hopkins & Clay 1952: 146, 150). We here provisionally place these two new species in Goniocotes due to their small size and the fact that their ocular setae are sexually dimorphic ( Mey 1997). However, Goniocotes rolandi is more closely related to the species Kéler (1939) included in Dictyocotes , whereas Goniocotes kristinae would belong to either Goniocotes sensu stricto or another yet undescribed genus.

Figures

FIGURES 14–15. Male genitalia of Goniocotes rolandi new species. 14, dorsal view. 15, ventral view.