Leielmis armipes, Bilton, 2018

Bilton, David T., 2018, A new species of Leielmis Delève, 1964, with a revised key to members of the genus (Coleoptera: Elmidae), Zootaxa 4441 (3), pp. 592-596 : 592-593

Leielmis armipes sp. nov. ( Figs 1-2 )

Type locality. South Africa, WeStern Cape, HeXrivier mountainS, Small Stream in Green Gulley below MoStertShoek TwinS, 1,200 m, 33° 28’ 26.64”S 19° 17’ 14.54”E ( Fig. 2C ).

Type material. Holotype (male): “ 14/ii/2017 South Africa WC// HeXrivierberge, Green Gulley // 1, 200 m, MoStertShoek TwinS// 33° 28’ 26.64”S 19° 17’ 14.54”E // Small Stream D T Bilton leg.” (genitalia eXtracted and mounted in DMHF on Same card) and red holotype label “ Leielmis armipes // Holotype // D T Bilton 2018 ” ( AMG).

Paratypes (18) 6 ♂ 4 ♀ same data as holotype ( CDTB, ISAM, NMW, SANC, TMSA) ; 4 ♂ 4 ♀ “ 14/ii/2017 South Africa WC// HeXrivierberge , Green Gulley // 1, 320 m, MoStertShoek TwinS// 30° 28’ 20.86”S 19° 17’ 14.61”E // Small Stream D T Bilton leg.” ( AMG, CDTB, ISAM). All with red paratype labelS “ Leielmis armipes // Paratype // D T Bilton 2018”.

Description. Size: Holotype: body length (front of pronotum to elytral apiceS) 1.65 mm; maXimum width (elytra) 1.0 mm; elytral length 1.10 mm. Same valueS for paratypeS: 1.50–1.60 mm, 1.0– 1.10 mm and 1.0– 1.15 mm reSpectively.

Colour: DorSum ( Fig. 1A ) dark brown to black, paleSt at anterior margin of pronotum and apeX of labrum. LegS reddiSh brown. Antennae dark yellow, Segment 11 infuScated. MaXillary palpi reddiSh brown; cardo and StipeS yellow. Labial palpi Straw yellow. Venter reddiSh brown; mentum paler; ligula yellow.

Head: Triangular, narrowed to apeX. Labrum triangular, with acuminately rounded apeX; approXimately 0.7X aS wide aS clypeuS, 0.5X aS long; weakly microreticulate, granulate and cloSely punctate, punctureS bearing curved, recumbent Setae. ClypeuS alSo Shining, weakly microreticulate and finely granulate and punctate, punctureS bearing curved, recumbent Setae. Frontoclypeal Suture feebly impreSSed; weakly arcuate. FronS Shining, with moderate, medium punctureS, bearing curved, recumbent Setae; moderately, coarSely granulate and microreticulate. EyeS occupying approXimately half Side of head; rounded anteriorly, relatively flat laterally and poSteriorly. MaXillary palpi with Segment 3 flat and eXpanded laterally, approXimately 2X broader and longer than Segment 4. Labial palpi with Segment 2 flat and eXpanded laterally, Segment 3 narrower and Shorter.

Pronotum: TranSverSe, 1.6X broader than long; broadeSt at poSterior margin, narrowing Strongly to front angleS; poSterior margin approXimately 1.2X width of anterior. Arched, anterior margin broadly arcuate in middle, forming a hood, which ShieldS much of the head. PoSterior margin biSinuate around centre. Lateral marginS Strongly bordered, weakly rounded. Anterior angleS acute; poSterior angleS obtuSely rounded. Surface ( Fig. 1B ) Shining, without evident microreticulation; doubly punctate, with SparSe, medium punctureS, interSperSed with moderate, fine punctureS, larger punctureS approXimately 3– 4X diameter of Smaller oneS. CoarSe punctureS bearing long, fine, golden, recumbent to decumbent Setae. CoarSely granulate between punctureS, eXcept on diSc.

Elytra: Slightly elongate, broadeSt approXimately one third of the diStance behind Shoulder, narrowing Strongly in poSterior third, to acuminately rounded apeX. PunctureS of rowS ( Fig. 1B ) widely Spaced, relatively evenly Sized throughout length. Puncture rowS 1–5 weakly Striate impreSSed on diSc; not Striate impreSSed behind middle and obSolete towardS apeX. IntervalS relatively flat ( Fig. 1B ), Shining, with microreticulation reduced to tranSverSe wrinkleS; finely punctate, punctureS bearing fine, golden, recumbent Setae; interval punctureS of two SizeS, fine and very fine, fine punctureS arranged in irregular rowS. Surface coarSely granulate poSterolaterally. Scutellum elongate, Shining, with no evident microreticulation; SparSely and finely punctate.

Venter: Entire Surface with denSe plaStron veStiture, eXcept poSterior genae and central portion of metaventrite and abdominal ventriteS 1–4; thoraX and abdomen with medium, curved, golden, recumbent Setae and rounded to elongateoval, coarSe, Shining granuleS. Anterior proSternal emargination relatively deep, v-Shaped. ProSternal proceSS approXimately 1.25X length of anterior portion of proSternum; quadrate, with raiSed lateral marginS and cloSe, mediumcoarSe punctureS; abruptly narrowing to bluntly acuminate apeX. Fovea at junction of meSo and metaventriteS Small and circular. Metaventrite ( Fig. 2A ) Shining, with no viSible microreticulation and medium, moderate punctureS. Sternite 9 with poSterior portion 2.5X length of anterior median Strut.

LegS: MeSo and metatibiae with characteriStic modificationS ( Fig. 1C ).

AedeaguS. PhallobaSe relatively Short, 0.6X length of peniS. PeniS longer than paramereS, curved apically in lateral view, with truncately acuminate apeX. ParamereS narrow, with Slightly incurved, rounded apiceS, and Slightly curved interior marginS (See Fig. 1D ).

FemaleS: AS maleS, eXcept for Slightly Shallower meSoventral concavity and lack of tibial modificationS. OvipoSitor elongate, diStal gonocoXite with relatively narrow apiceS ( Fig. 1E ); 0.7X length of proXimal gonocoXite.

Variation: SpecimenS vary in the degree to which they retain dorSal Setae and granuleS, both of which are apparently worn off in Some individualS.

Differential diagnosis. The SpecieS iS morphologially cloSe to L. georyssoides and L. gibbosus , from which it iS moSt reliably diStinguShed on the baSiS of the prominent internal Spine on the male metatibia ( Fig. 1C ), a character entirely abSent in both theSe SpecieS. It alSo differS from theSe taXa in itS Somewhat paler colouration (dorSum, venter and appendageS), the SparSer punctation on the pronotum and venter (particularly on the metaventrite – See Fig. 2A–B ), and the more widely Spaced punctureS of the elytral SerieS. The male genitalia are cloSeSt to L. georyssoides , but differ from thiS SpecieS in the Stouter, Shorter peniS apeX, which doeS not project aS far beyond the paramereS. The diStal gonocoXite of femaleS haS narrower apiceS than Seen in L. georyssoides .

Distribution and ecology. So far known from a Single high altitude permanent Stream in the HeXrivier mountainS, WeStern Cape Province, South Africa. Here it occurred together with the relatively wideSpread L. gibbosus .

Etymology. Named in reference to the modificationS to the male metatibiae.

Figures

FIGURE 1. Leielmis armipes sp. nov. A) holotype male, dorSal habituS; B) paratype female, detail of dorSal Sculpture; C) holotype male, meSo and metatibia, dorSal view; D) holotype male, aedeaguS, ventral and lateral viewS; E) paratype female, ovipoSitor, diStal gonocoxite. Scale barS = A) 1 mm; B) –E) 0.25 mm.

FIGURE 2. Leielmis SpecieS. A) L. armipes sp. nov., venter; B) L. gibbosus venter; C) South Africa, WeStern Cape, Hexrivier mountainS, Small Stream in Green Gulley below MoStertShoek TwinS, 1,200 m, type locality of L. armipes sp. nov. Scale bar = 0.25 mm.