Acylophorus acufer Lott

Lott, Derek A., 2012, Further studies of African Acylophorus Nordmann (Coleoptera: Staphylinidae: Staphylininae), Zootaxa 3168, pp. 39-52 : 49

Acylophorus acufer Lott , new species

( Figs 23–28 )

Description. Length 5.5 –6.5mm. Body black except for dark chestnut margins of pronotum and the apical abdominal tergites, which are paler at both base and apex. Abdomen iridescent to varying degrees. Legs red. Antennae pale or dark with segment I always pale at base. Maxillary palpi usually all pale.

Head small (pronotum 2.1x wider than head), more or less as long as wide with wide neck and temples barely suggested ( Fig. 23 ). Antennae inserted right on front margin with no pigmented area in front. No micro-punctures visible at 80x magnification. Short pubescence behind eyes localised and sparse. Two pairs of interocular setae arising from foveate punctures much closer to eyes than each other and five postocular setae visible from above on each side. No extra seta by hind margin of eye. Mandibles short with wide basal flange, a vestigial medial tooth discernible on the left mandible ( Fig. 24 ). Maxillary palpi with terminal segment densely pubescent, narrow and more or less symmetric, longer than penultimate segment, which is short, triangular and glabrous ( Fig. 25 ). First segment of antenna as long as next four ( Fig. 26 ). Segments I to V elongate, VII to XI transverse.

Pronotum slightly transverse (1.2x wider than long) with rounded sides and widest in basal half. Shining with no micro-punctures. One pair of dorsal setae. One pair of lateral setae. Marginal setae long. Elytra strongly transverse (1.7x wider than long) with pubescence arising from fine, asperate punctures. Fringe of bristles on hind margin longer than the hairs on the rest of the elytra. Empodial setae between claws on mid- and hind tarsi very short. Asperate punctures on abdominal tergites denser at base, pubescence longer than on elytra.

Male with apex of sternite IX entire. Paramere bilobed, each lobe long and pointed, needle-shaped, much longer than median lobe of aedeagus, pegs confusedly arranged around or slightly in front of mid-point of each lobe ( Figs 27 and 28 ). Median lobe barely expanded at apex which is rounded.

Type material. Holotype 3: “ Namibia 30.iii.1999 18O14’S / 21O43’E Mahango GR, Kwetche piknik site, banks of Okavango, shore washing, lg M. + B. Uhlig / HOLOTYPE Acylophorus acufer sp. n. 3 det. DA Lott, 2010 ” ( ZMHB). Paratypes 536Ƥ same data as holotype ( ZMHB, cJanak); 3: “NAMIBIA-Exp. ZMB 1992 Mahango Game Reserve, Seeufer, Ufervegetation gesiebt, 18O17’S / 21O43’E 28.II.92, leg M. Uhlig” ( ZMHB); 1Ƥ: “ NAMIBIA 24.xi.1993 18O14’S / 21O43’E Kavango: Mahango Game Reserve: Okavango Papyrus sievings, leg Uhlig” ( ZMHB); 8: “ NAMIBIA 1+ 4.iii.1994 Kavango: Piknik site, Okavango banks, sievings, flood refuse, reed leaf litter, grass leg M. Uhlig” ( ZMHB); 131Ƥ: “ NAMIBIA 1+ 4.iii.1994 18O14’S / 21O43’E Kavango: Mahango Game Reserve, Baobab, Okavango banks, sievings, flood refuse, leg M. Uhlig” ( ZMHB); 6: “NAMIBIA-Exp. ZMB 1992 Buffalo Camp, Kavango-Ufer, Ufervegetation gesiebt, 18O09’S / 21O42’E 28.II.92, leg M. Uhlig” ( ZMHB); 6: “NAMIBIA-Exp. ZMB 1992 Popa Falls, Kavango-Ufer, Ufervegetation gesiebt, 18O07’S / 21O35’E 27.II.92, leg M. Uhlig” ( ZMHB); 97: “NAMIBIA-Exp. ZMB 1992 Popa Falls, Kavango-Ufer, Schilf – Papyrus - Ufervegetation gesiebt, 18O07’S / 21O35’E 2.III.92, leg M. Uhlig” ( ZMHB); 16: “NAMIBIA-Exp. ZMB 1992 Popa Falls, 18O07’S / 21O35’E Kavango-Ufer, Schilf – Papyrus - Ufervegetation gesiebt, 13.III.92, leg M. Uhlig” ( ZMHB); 8: “ NAMIBIA 1.iv.1993 18O07’16”S / 21O34’51”E Popa Falls, island banks of Okavango banks, reed - papyrus sievings, leg Uhlig” ( ZMHB); 7: “ NAMIBIA 17.iv.1993 18O07’16”S / 21O34’51”E Popa Falls, island banks of Okavango banks, sievings: reed + papyrus, leg M. Uhlig” ( ZMHB); 5: “ NAMIBIA 28.ii – 6. iii.1994 18 O07’16”S / 21O34’51”E Popa Falls, Okavango banks, sievings, Papyrus, reed, grass, leaf litter, leg M. Uhlig” ( ZMHB); 5: “ BOTSWANA 3.iii.1994 18O48’S / 22O08’E Sepupa, Okavango-Delta, sievings: grass + flood refuse, leg M. Uhlig” ( ZMHB); 1Ƥ: “ BOTSWANA 6.iv.1998 Shakawe Fishing Camp 18O27’S / 21O56’E leg J. Deckert, gesiebt” ( ZMHB).

Distribution and bionomics. All records to date of this species come from the Okavango River system in Botswana and Namibia, where it appears to be the most frequently collected species of Acylophorus . Specimens were mainly obtained by sieving marsh litter, but a few specimens were collected by splashing riverbanks.

Comparative notes. This species can be distinguished from both A. salifi and A. lomaensis by the less transverse pronotum, the more slender last segment of the maxillary palpi and, above all, by the form of the male genitalia. In addition, it is larger and darker than A. lomaensis . Populations of A. salifi occurring along the Okavango appear to be of the typical colour form (mainly black with reddish elytra), so colour may be an additional character that is useful for distinguishing A. acufer and A. salifi in the field.

Etymology. This specific name is a noun in apposition meaning “bearer of needles”, a reference to the extraordinary shape of the parameres.

Figures

FIGURE 23. Distribution of Acylophorus lomaensis Levaisseur.

FIGURES 24 – 29. Acylophorus acufer sp. n. 24, fore body; 25. mandibles; 26, maxillary palp; 27, antenna; 28, aedeagus (ventral and lateral views); 29, internal face of paramere.