Psammonirmus Bush 2017, new genus
Creators: name: Bush, Sarah E.
Publisher: name: Zenodo
Year: 2017
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Phthiraptera
Philopteridae
Psammonirmus

description: Psammonirmus Gustafsson & Bush, new genus
Type species. Psammonirmus lunatipectus new species
Diagnosis. Psammonirmus n. gen. does not appear to be closely related to any other genus treated here. pns is absent in Psammonirmus (Fig. 148) as in Brueelia s. str (Fig. 44), and like in Brueelia s. str. (Figs 42–43) females of Psammonirmus (Fig. 147) have very few abdominal setae, while males (Fig. 146) have few setae in anterior segments and several tps in more posterior segments (see Table 2). Moreover, Brueelia s. str. lack as3 (Fig. 44), but as3 is present in Psammonirmus (Fig. 148). With the exception of Br. phasmasoma n. sp. (Fig. 58), no known Brueelia s. str. have a dorsal preantennal suture, but this is present in Psammonirmus (Fig. 148), and extends as in some Acronirmus (Fig. 85). Psammonirmus is separated from species of Brueelia s. str. with dorsal preantennal suture and Acronirmus by the following characters: s4 present in Psammonirmus (Fig. 148) but absent in Brueelia s. str. (Fig. 58) and Acronirmus (Fig. 85); pos absent in Psammonirmus (Fig. 148) and Acronirmus (Fig. 85) but present in Brueelia s. str. (Fig. 58); female tergopleurites IX+X and XI partially fused in Psammonirmus (Fig. 147) but not fused in Brueelia s. str. (Fig. 57) and Acronirmus (Fig. 84); ss present on male tergopleurites II–IV, psps present on male tergopleurite IV, and tps present on male tergopleurites V–VI in Psammonirmus (Fig. 146), but all these sets of setae absent in Brueelia s. str. (Fig. 56) and Acronirmus (Fig. 83); mesosomal lobes extended laterally overlapping with parameres in Psammonirmus (Fig. 149) but not extended in Brueelia s. str. (Fig. 59) or Acronirmus (Fig. 86).
The male genitalia of Psammonirmus (Figs 149–151) are similar only to those of Hecatrishula n. gen. (e.g. Figs 134–136, 142–144) and Ceratocista n. gen. (Figs 157–159). As in Hecatrishula (Figs 134–135, 142–143), the mesosomal lobes are extended laterally, overlapping the parameres in Psammornirmus (Figs 149–150); in both genera the gonopore is slightly elongated distally, the proximal mesosome is small, the parameral heads are at least bifid (Figs 136, 144, 151), and the lateral margins of the mesosomal lobes are pectinate. However, in Psammonirmus (Fig. 149) the lateral extensions of the mesosomal lobes are dorsal to the parameres, whereas in Hecatrishula they are ventral (Figs 134, 142). In addition, the ventral U- or V-shaped sclerite present in Hecatrishula (Figs 135, 143) is absent in Psammonirmus (Fig. 150), and while the pmes are visible as stout setae positioned on the postero-ventral surface of the lobes in Hecatrishula (Figs 135, 143), these are much smaller and positioned on the lobes in Psammonirmus (Fig. 150). Abdominal chaetotaxy differs between the two genera (Table 2), with Hecatrishula having psps and tps on all segments in both sexes (Figs 130–131, 138–139), whereas in Psammonirmus anterior segments of the male (Fig. 146) have only ss and are entirely nude in female (Fig. 147). as3 is present in both Hecatrishula (Figs 132, 140) and Psammonirmus (Fig. 148), but pns is present in Hecatrishula and absent in Psammonirmus.
Lateral extensions of the mesosomal lobes are found also in Ceratocista (Figs 157–158), and in both this genus and Psammonirmus these extensions are dorsal. The abdominal chaetotaxy is remarkably similar in the two genera (Table 2). In both Ceratocista (Fig. 154) and Psammonirmus (Figs 147) female tergopleurites IX+X and XI are partially fused. The female subgenital plates of both genera are also very similar, however the cross-piece is medianly displaced in Ceratocista (Fig. 160) but medianly continuous in Psammonirmus (Fig. 152). Antennae are sexually dimorphic in Ceratocista (Figs 155–156) but not in Psammonirmus (Fig. 148), and the preantennal structure is very different in these two genera. In Ceratocista (Fig. 155) the frons is sclerotized dorsally as in Resartor n. gen. (Fig. 163) or Turdinirmus (Fig. 182), but in Psammonirmus (Fig. 148) the frons is hyaline, and the dorsal preantennal suture completely separates the dorsal anterior plate from the main head plate.
Description. Both sexes. Head trapezoidal (Fig. 148). Marginal carina interrupted submedianly and laterally; absent at osculum. Dorsal preantennal suture continuous with hyaline margin, reaching dsms and ads, posteriorly separating dorsal anterior plate from main head plate. Ventral carinae diffuse anterior to pulvinus, and not clearly continuous with marginal carina. Ventral anterior plate absent. Head setae as in Fig. 148; pos and pns absent. Coni small, pointed. Antennae monomorphic. Temporal carinae not visible; mts 3 only macrosetae. Gular plate broad, pentagonal.
Prothorax rectangular (Figs 146–147); ppss on postero-lateral corner. Proepimera with hammer-shaped median ends. Pterothorax pentagonal, with posterior margin convergent to rounded median point, differing slightly in shape between sexes; mms widely separated medianly. Meso- and metasterna not fused; 1 seta on postero-lateral corner on each side of each plate. Metepisterna widened medianly. Leg chaetotaxy as in Fig. 25, except fI-v4, fI-p2, fII-v2, fIII-v2 absent.
Abdomen (Figs 146–147) oval in female, more teardrop-shaped in male. Tergopleurites rectangular, but triangular in more posterior tergopleurites in male; tergopleurites II–IX+X in male and tergopleurites II–VIII in female moderately separated medianly. Tergopleurite IX+X and XI fused in female. Sternal plates rectangular, transversally continuous, not approaching pleurites. Pleural incrassatons moderate. Re-entrant heads prominent. Abdominal chaetotaxy as in Table 2 and Figs 146–147; pss cannot be seen in any material examined, and lateralmost seta on all tergopleurites (except pleural setae) here tentatively interpreted as psps with shorter seta median to this in females tentatively interpreted as tps. Male subgenital plate trapezoidal, reaching posterior margin of abdomen. Female subgenital plate trapezoidal, but diffuse distally. Cross-piece present, but from the material examined it cannot be established whether this is detached or continuous with subgenital plate. Vulval margin (Fig. 152) with slender vms, numerous thorn-like vss; vos follow lateral margins of subgenital plate; distal setae not approaching vss.
Basal apodeme rounded rectangular (Fig. 149). Proximal mesosome small, constricted at about midpoint. Gonopore (Fig. 150) prominent, open distally, with lateral extensions in anterior end. Mesosomal lobes large, wing-like, overlapping with parameres. Distal margin of lobes pectinate; 2 pmes sensilla visible on each side of gonopore (Fig. 150). Parameral heads bifid (Fig. 151). Parameral blades slender, tapering; pst1–2 not visible.
Host distribution. Psammonirmus lunatipectus n. sp. is the first species of Brueelia -complex described from the Eurylaimides, and is presently know only from the Eurylaimidae. A pair of specimens (NHML, 1980-40 and 1934-570) from Psarisomus dalhousiae dalhousiae (Jameson, 1835) belong to this genus, but the male genitalia are too badly distorted to ascertain whether these are Ps. lunatipectus. Notably, the head shape of the material from P. d. dalhousie varies from that of Ps. lunatipectus from Serilophus lunatus.
We have examined material from other Eurylaimidae, including Eurylaimus steerei mayri Salomonsen, 1954, Cymbirhynchus macrorhynchus malaccensis Salvadori, 1874, Corydon sumatranus laoensis Meyer de Schauensee, 1929, and Calyptomena viridis caudacuta Swainson, 1838, but all specimens from these hosts belong to Guimaraesiella. We have seen no Brueelia -complex lice from the other members of Eurylaimides (Pittidae, Philepittidae, Sapayoa Hartert, 1903). The two known hosts of Psammonirmus are nested within the Eurylaimidae, but are not closely related within that family (Moyle et al. 2006). It is puzzling that these two hosts, but none of the others, are parasitised by Psammonirmus; poor sampling may be a factor.
Geographical range. Southeast Asia.
Etymology. The genus name is derived from Greek “ psammos ” for “sand”, and refers to the coloration of the only known species. “ Nirmus ” is a common generic suffix in louse taxonomy, referring to Nitzsch (1818) genus of the same name. Gender: masculine.
Remarks. No representative of Psammonirmus was included in the phylogeny of Bush et al. (2016), and its relationship to other genera treated here is presently unknown.
Included species
* Psammonirmus lunatipectus new species
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 95-97, DOI: 10.11646/zootaxa.4313.1.1, http://zenodo.org/record/883161