Neoperla bipolaris, Zwick & Zwick, 2023

Zwick, Peter & Zwick, Andreas, 2023, Revision of the African Neoperla Needham, 1905 (Plecoptera: Perlidae: Perlinae) based on morphological and molecular data, Zootaxa 5316 (1), pp. 1-194 : 99-101

42. Neoperla bipolaris n. sp.

( Figs. 223–226 )

Type material: 1♀ holotype ( NEOP175 , slide DNA390) , 2♀ paratypes ( NEOP176 ) , Republic of Angola, 21.XI.13, Cuanza Norte Prov., 20km W N’dalantando [9.30S, 14.92E], 337m, P. Schuele leg. -18- ( SMNS) .

Additional material: 1♀, [ United Republic of Tanzania] Tanganyika, 23-II-62, T. Williams ( USNM; after figs 29, 30 in T. Moore, 1991) .

Habitus. WL 12.2–13.2mm. Body yellow, center of head ochre, tentorial calluses, M-line and anterolateral lobes darker, grey. Head light yellowish grey along eyes and on occiput, an arched black fascia along the occipital suture, a sharp tip projecting forward from between ocelli. Antenna and cercus blackish, segments 1–3 lighter. Palpi with grey tips. Pronotum dark ash grey. Mesonotum between wings bases yellowish brown. Femora dorsodistally dark grey, half of foreleg, ¼ of hind leg, upper edge of knee yellow in all. Tibiae dark except very tip, tarsi dark. Wings blackish-grey, veins dark except brownish on a short basal stretch of costal space. Front wings darker than hind wings.

Male. Unknown.

Female ( Fig. 226 ). Anterior half of S8 with diffuse transverse brown macula, otherwise unmodified. Vagina shorter than sternite, base slender, anterior portion with attachment of oviduct and SSt wider. A patch of slender straight spines of variable size on either side of stalk. SSt short, stout forming an incomplete ring, base longitudinally folded and wrinkled. The armature of triangular scales forms a narrow basal strip which widens quickly, covering entire diameter and ending at a short distance from attachment of spermathecal duct and the curled spermatheca.

Egg ( Figs. 223–225 ).335*200µm, stout, drop-shaped, operculum rounded, anchor pole flat, width corresponding to 1/3 of maximum egg width ( Figs. 223, 225 ). Chorion with dense unordered punctures, at both poles there are low impunctate radial ribs amongst the punctures ( Fig. 224 ). At the anchor pole ribs are connected to a ring of cells on the sessile collar, on the broad operculum ribs are connected to a network of delicate polygones, reminiscent of striate eggs. Micropyles are unmodified and exposed ( Fig. 224 , arrow). Anchor mushroom-shaped with long solid stem, the anchor cavity is deep, funnel-shaped.

DNA ( Figs. 492 , 496 ). The female holotype and female paratype from Angola were sequenced for the COX1 DNA barcode fragment. They cluster together with near maximum support (98.4/100/100), and the species is maximally supported (100/100/100) as sister to N. schuelei n. sp..

Note. The chorion structure near the egg poles suggests ancestors of N. bipolaris had striate eggs.

Etymology. The name is a Latin adjective referring to the occurrence of rudimentary striae near both egg poles.

Figures

FIGURE 492. Simplified overview of codon-model maximum likelihood phylogram based on 356 mitochondrial genome and COX1 DNA barcode sequences (all-NT). Terminal labels include information on the species only. Clades of particular interest highlighted with colours that correspond to the clades in other trees. The full tree is shown in Figs 493-498.

FIGURE 496. Partial (clades G, H) codon-model maximum likelihood phylogram based on 356 mitochondrial genome and COX1 DNA barcode sequences (all-NT). See Fig. 493 for common details.

FIGURES 223–226. Neoperla bipolaris n. sp.: 223, 224, egg, SEM micrograph (from Moore, 1991); 225–226, egg and genital situs of holotype. FIGURES 227–230. Neoperla schuelei n. sp.: 227, female genital situs, paratype; 228–230, egg from holotype; 229, enlarged detail of chorion; 230, oblique view of anchor pole showing the relation between striae and cells on collar. Scale lines are 100µm, unless differently indicated. Arrows indicate micropyles.