Neoperla decorata, 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 : 54

20. Neoperla decorata n. sp.

( Figs. 96–98 )

Type material studied: Republic of Cameroon, Holotype ♀: 5°1’17.65’’N, 9°46’10.39E, SW-Reg., 7km S Bangem, Ebonmin , coffee plantation, 1470m asl, 29 Oct 2011, MV-lamp, A.Zwick & D.Bartsch ( NEOP053 ; 2 slides; SMNS).

Habitus. WL 15.0mm, Rs with 3 forks, front wing patterned by clear areas on dark grey ground ( Fig. 96 ): Costal space clear, rest of basal half largely dark. Veins and membrane of same colour, except base of Rs and several vein sections along cord almost black. Dark crossveins in medio-cubital and cubito-anal space with narrow light borders. Distal half of wing lighter, distally from cord with a large clear area subdivided by a curved subapical fascia.

Vertex orange-ochre, ocellar rings separate; frontoclypeus with greyish shades; occiput and along inner edge of eyes pale ochre. Pronotum infuscate with dark wrinkles, including a pair of paramedian parallels. Mesonotum with pale median spot, next to wing base a dark brown macula. Sides of meso- and metathorax with a dark fascia on pale ground. Abdomen and cercus pale, yellowish.

Antenna, palpi and legs blackish, inner edge of femur and tibia, tibial apex and most of tarsus lighter, especially on hind leg.

Male. Unknown.

Female ( Fig. 97 ). S7 with mediocaudal spot, S8 light brown in the front half and on a medial stripe attaining the firm concave caudal edge which is almost bare. Vagina slender, long, extending into S7, unmodified. The SSt forms about 1.5 rings of uniform diameter, about the basal third is modified, with scales only near the vonvex edge. Scales tightly packed like roof tiles similar to Fig. 108 , spermatheca (not shown in the figure) coiled.

Egg ( Fig. 98 ). Ovoid, plump, 430*245µm, collar inflated, at its base the chorion is thick and the egg contour is constricted. Anchor cavity large, transversely oval, edge of opening thickened. Anchor stem long, rolled in the cavity when it is covered by the cap, long and thin when exposed. With 12 to 13 straight ridges between base of collar and the rounded top of operculum, the micropyles are exposed. The chorion resembles corrugated iron, with very fine dense unordered punctures everywhere, except on the collar. No eclosion line, no cells.

Notes. We know of no other African Neoperla with patterned wings. Elsewhere occur several Neoperla species with wing patterns, e.g., N. variegata Klapálek, 1909 and N. alboguttata Zwick, 1986 from Borneo. Both are members of the so-called N. montivaga -group and are otherwise very different from N. decorata .

DNA ( Figs. 492–493 ). The female holotype from Cameroon was sequenced for the COX1 DNA barcode fragment. The species is moderately well supported (49.1/99/91) as sister to N. planidorsum n. sp., and both species together with similar support (73.9/98/0) as sister to N. cataractae n. sp..

Etymology. The name is the female gender of the Latin adjective decoratus, ornate, an allusion to the patterned wings.

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 493. Partial (outgroup, clades A, B, D) codon-model maximum likelihood phylogram based on 356 mitochondrial genome and COX1 DNA barcode sequences (all-NT). Statistical support values above branches or near nodes are SH-aLRT and UFBoot for the codon-model analyses, followed by NT123 UFBoot. Terminal labels include information on the species, type status, gender, originating country, unique sequence identifier (NEOP###), sequencing approach and total basepairs of 13 mitochondrial, protein-coding genes. Clades of particular interest highlighted with colours that correspond to the clades in other trees. See Fig. 492 for an overview. HT = holotype; PT = paratype; PCR = Polymerase Chaine Reaction; WGS = Whole Genome Shotgun.

FIGURES 96–101. Neoperla decorata n. sp. and N. cataractae n. sp., the holotypes. N. decorata: 96, front wing; 97, genital situs, diagrammatic, spermatheca removed; 98, egg. N.cataractae: 99, female genital situs, diagrammatic, spermatheca removed; 100, 101, egg, side view and optical cross section (from a photograph). Scales are 100µm, other figures not to scale. a, anchor; c, collar; mi, micropyle; op, operculum; os, opercular suture; sd, spermathecal duct, SSt, spermathecal stalk, V vagina.

FIGURES 108–113. Neoperla spp., structural details.108, N. africana Klap., 109, N. kalengonis n. sp., 110, N. sjostedti needhami Lestage, all from the stream Kalengo: 108, 109 scales in the SSt. Close-ups of egg chorion: 110, three egg striae, the 2 rows of micropunctures in the sulci diverge around an island with a micropyle; 111, N. africana, 112 N. camerunensis (End.), chorion with 2 micropyle orifices; 113, processes of tergites 7 and 8, and modifications of antecosta 8 (AC8), a combination of inner structures (light grey), and of fine pilosity and sclerites (dark grey) on the surface of tergites; diagrammatical. The SEM microgaphs are courtesy of MPI of Limnology, PL̂n.