Corvonirmus Eichler 1944
Creators: name: Bush, Sarah E.
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Phthiraptera
Philopteridae
Corvonirmus

description: Corvonirmus Eichler, 1944
Docophorus Nitzsch, 1818: 289 (in partim). Nirmus Nitzsch, 1818: 291 (in partim). Degeeriella Neumann, 1906: 60 (in partim). Brueelia Kéler, 1936a: 257 (in partim). Corvonirmus Eichler, 1944: 80.
Type species. Nirmus uncinosus Burmeister, 1838: 430, by original designation.
Diagnosis. Corvonirmus is superficially similar to Hecatrishula n. gen., expecially the He. atherae species group, with which it shares the following characters: tergopleurites reduced, not or barely reaching lateral margins of abdomen (Figs 130–131, 319–320); one or more fenestrae on tergopleurites, which may be perforated medianly (Figs 130–131, 319–320); pigmentation limited; dorsal preantennal suture absent (Figs 132, 321); marginal carina not interrupted but displaced dorsally and posteriorly at osculum (Figs 132, 321); antennae may be sexually dimorphic (Figs 132–133, 319–320); accessory sts on at least some segments in both sexes (Figs 130–131, 319– 320); ppss median to pronotal spiracle opening (Figs 130–131, 319–320); psps present on tergopleurite III in both sexes (Figs 130–131, 319–320); tps present on tergopleurites III–IV in at least male (Figs 130–131, 319–320). Corvonirmus can be separated from Hecatrishula by the following characters: aps present on at least some segments in male Corvonirmus (Table 2), but absent in all segments in Hecatrishula; female subgenital plate flares into cross-piece in Corvonirmus (Fig. 326) but not in Hecatrishula (Fig. 137); tps present on tergopleurite II in female Hecatrishula (Fig. 131) but absent in female Corvonirmus (Fig. 320); as3 is present in both sexes of Hecatrishula (Fig. 132), but is absent in Corvonirmus (Fig. 321). Males of Corvonirmus are best separated from male Hecatrishula by the genitalia: proximal mesosome small with little or no overlap with basal apodeme in Hecatrishula (Fig. 134), whereas in Corvonirmus (Fig. 323) the proximal mesosome is large and overlaps substantially with the basal apodeme; parameral heads complicated and at least bifid (Fig. 136) in Hecatrishula, but rectangular and folded medianly in Corvonirmus (Fig. 325); mesosomal lobes splayed, not fused distally in Hecatrishula (Figs 135), but gently rounded, fused distally in Corvonirmus (Figs 323–324); parameres strongly convergent distal to mesosome in Hecatrishula (Fig. 134), but much elongated and gently tapering in Corvonirmus (Fig. 325); pst1 lateral microseta in Hecatrishula (Fig. 136), but central sensillus in Corvonirmus (Fig. 325).
Description. Both sexes. Head indented-dome shaped (Fig. 321), but variable between species. Marginal carina uninterrupted, displaced dorsally and posteriorly at osculum. Ventral carinae typically continuous with marginal carina. Dorsal preantennal suture, dorsal anterior plate, and ventral anterior plate absent. Head setae as in Fig. 321; as3 absent; pns microseta. Preantennal nodi large, often with “hollowed-out” look. Coni typically broad but short, blunt, largely triangular. Antennae typically sexually dimorphic, scapes longer and thicker in males than in females; in some species antennae are almost monomorphic. Preocular nodi located median to eyes. Temporal carinae not visible; mts 3 only macrosetae. Gular plate triangular. Patterns of pigmentation on head often diagnostic to species level.
Prothorax rectangular (Figs 319–320); ppss located median to spiracle opening. Proepimera slender, long, reaching around coxae II. Pterothorax pentagonal; lateral margins widely divergent; posterior margin convergent to median point; mms widely separated medianly. Meso- and metasterna not fused; 1 seta on posterior margin on each side of each plate. Metepisterna slender, median ends blunt. Leg chaetotaxy as in Fig. 25, except fI-p2 absent; fI-v4 long, spike-like.
Abdomen broad, rounded (Figs 319–320), largely translucent, with tergopleurites and sternal plates densely pigmented. Abdominal chaetotaxy as in Table 2; accessory sternal setae may be present. Tergopleurites do not or just barely reach the lateral margins of the abdomen; often much reduced (except in Indo-Malayan and Australasian species) to small, roughly hook-shaped plates; one or more fenestrae on most tergopleurites, the median-most of which may be penetrated medianly; tergopleurites II–IX+X in male and II–VIII in female widely separated medianly. Pleural incrassations typically absent, but narrow incrassations present on at least some tergopleurites in some Indo-Malayan and Australasian species (not illustrated). Sternal plates rectangular, wide, short, not approaching lateral margins of abdomen. Male subgenital plate broadly triangular, reaching posterior margin of abdomen. Female subgenital plate roughly triangular, reaching to vulval margin. Lateral submarginal extensions or cross-piece present. Abdominal chaetotaxy as in Table 2 and Figs 319–320. Vulval margin (Fig. 326) with slender vms, thorn-like vss; vos follows lateral margins of subgenital plate.
Male genitalia (Figs 323–325) large, often reaching anteriorly to segment V or VI, variable in shape. Basal apodeme rounded or rectangular. Proximal mesosome large, rectangular, overlapping with basal apodeme. Prominent ventral ridges converge on gonopore. Gonopore (Fig. 324) subterminal, open distally, with broad, scaled lateral extensions. Mesosomal lobes broad, blunt, fused distally; 2 ames microsetae on each side submedianly anterior to gonopore; 1 pmes sensillus on each side on lateral extensions of gonopore; 1 pmes sensillus on each side on lateral margin of mesosome. Parameral heads (Fig. 325) folded, more or less rectangular, typically oblique. Parameral blades elongated, triangular; pst1–2 sensilla, central, near distal end of parameres.
Host distribution. Species of Corvonirmus are known only from members of the host genus Corvus Linnaeus, 1758.
Geographical range. Global except the Neotropics. This may reflect the fact that, apart from Central America and the Caribbean, there are no species of the genus Corvus in the Neotropics (Madge & Burn 1999).
Remarks. In the phylogeny of Bush et al. (2016), Corvonirmus was represented by only two species, which were placed in disparate parts of the tree, in both cases with very low support. Thus we cannot be certain about this phylogenetic placement. Future phylogenetic analyses with additional species will help to elucidate the position of Corvonirmus within the Brueelia -complex.
Included species
* Corvonirmus afzali (Ansari, 1957a: 154) n. comb. [in Brueelia] * Corvonirmus argulus (Burmeister, 1838: 430) [in Nirmus] [1] * Corvonirmus hamatofasciatus (Piaget, 1890: 225) n. comb. [in Docophorus] * Corvonirmus latifasciatus (Piaget, 1880: 143) n. comb. [in Nirmus] * Corvonirmus leucocephalus (Nitzsch [in Giebel], 1866: 365) n. comb. [in Nirmus] * Corvonirmus mollii (Ansari, 1957a: 160) n. comb. [in Brueelia]
* Corvonirmus perwienae (Ansari, 1957a: 168) n. comb. [in Brueelia]
* Corvonirmus quadrangularis (Rudow, 1869: 18) n. comb. [in Nirmus] Nirmus bipunctatus Rudow, 1870: 467
* Corvonirmus rotundatus (Osborn, 1896: 226) n. comb. [in Nirmus]
* Corvonirmus saliemi (Ansari, 1957a: 158) n. comb. [in Brueelia]
* Corvonirmus tasniemae (Ansari, 1957a: 152) [in Brueelia]
* Corvonirmus theresae (Ansari, 1957a: 150) n. comb. [in Brueelia]
* Corvonirmus uncinosus (Burmeister, 1838: 430) [in Nirmus] Brueelia uncinosa plena Ansari, 1957a: 158
* Corvonirmus variegatus (Ansari, 1957a: 153) n. comb. [in Brueelia]
[1] Ansari (1957b: 157) stated that material from Corvus corax ruficollis [as Corvus ruficollis] in the Meinertzhagen collection was "indistinguishable" from Brueelia argula. Further, he noted (ibid.: 163) that additional material from the same host species was indistinguishable from Brueelia atherae. In both cases, Ansari refers to 20 males and 6 females. All the material we have examined from this host in the Meinertzhagen collection belongs to an undescribed species of Hecatrishula. We assume that Ansari (1957b) inadvertently referred to the same material twice, and therefore we have removed Corvus ruficollis as a host of Corvonirmus argulus.
description: Published as part of Bush, Sarah E., 2017, Morphological revision of the hyperdiverse Brueelia - complex (Insecta: Phthiraptera: Ischnocera: Philopteridae) with new taxa, checklists and generic key, pp. 1-443 in Zootaxa 4313 (1) on pages 193-195, DOI: 10.11646/zootaxa.4313.1.1, http://zenodo.org/record/883161