Neoperla amoena, 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 : 74-76

29. Neoperla amoena n. sp.

( Figs. 161–168 )

Type material: Holotypus: Republic of Mali, Bafing bei Tinko (N 13°29’ 54’’ / W 10° 45’ 19’), light trap, W. Tobias, 23.9.1993 ( NEOP070 ; SMNS) .

Paratypes: 1♁, 29.9.1991; 2♁, 1♀; 1♁, 2.9.1992; 6♁, 11.– 12.8.1993; 10♁, 1♀, 23.9.1993; 1♁, 24.9.1993, same locality and collector as holotype. 10♁, 1♀ ( NEOP071 ), Republic of Guinea, 10°28’40’’N, 10°26’42’’W, Faranah, F. Niger, Somorye , 20.06.1996 (Slide Z 16/14) ( SMNS, gift R. Fochetti). Republic of South Sudan: 1♁, South Sudan : Musée du Congo Soudan: Rejaf [4.75, 31.583333] 1923 L. Burgeon \ R. dét. 1647 \ Neoperla haugi Nav. P. Navás S. J. det. ( NEOP072 ; MRAC) .

Additional material studied: Republic of Guinea: 1♁, Milo à Boussoulé 23.10.1984 J.M.Gibon; ♁, Riv. Milo à Kankan (bassin du Niger) 26.10.1984 J.M.Gibon . Republic of Liberia, 8 mi NW Belefuanai , S fork S.Paul R., 11.8.66, Ross & Lorenzen ( CASENT 8413124 , Slide Z19.32; NEOP069 ) . Republic of Mali: 2♁, 1♀, Niger à Bamako [12.59°N, 8.06°W, 487m] 14.10.1984 J.M.Gibon (slides 16.27 & 16.192) . Republic of Senegal: 1♀, Touba [14.87°N, 15.88°W] août 1982 ( SMNS, gift Élouard; slide 16.196) .

Habitus ( Fig. 161 ). WL of males 8.8–10.2mm (n=14), of females 12.7–13.3mm. Sexes differ in colour, male holotype bright yellow, with blackish marks. An arched fascia along occipital suture tapers towards the eyes in the middle it is connected to the ocellar mark. Occiput bright yellow, frontoclypeus weakly infuscate. Palpi and scapus yellow, pedicellus and flagellum dark brown. Pronotum light brown, wings chocolate brown, Rs with 2 terminal branches. Base of femora bright yellow, distal third and all tibiae and tarsi dark brown. Female light ochre, the turbid wings and the tibiae infuscate.

Male ( Figs. 162–166 ). From the membranous caudal area of T7 rises a dark blunt pyramidal process with some SB near tip and on underside, it projects over front of T8. T8 flat, membranous except for a caudally narrowing median sclerite band with some SB, under the T7 process. T9 with a median furrow behind the divided antecosta. Sclerites extend from the low pilose lateral humps into the furrow where they are connected, resulting in a V-shaped pattern. HT 10 in dorsal view curved, the sharp tip directed forward, mediobasal callus conical, relatively narrow, tips partly concealing the small, Y-shaped epiproct.

Penis slender, straight, no spines on tube ( Fig. 164 ). Dorsodistal membranous area with a patch of closely appressed spines directed distad (Fig., 166). Endophallus about as long as penis, wide, gently curved, distally gradually narrower. Basal half bare, distally with scattered spines, mainly dorsally. Largest spines close to base, distal spines smaller, more numerous, on almost entire diameter, some small spines also ventrally, near tip ( Fig. 165 ).

Female ( Fig. 167 ). Generally similar to the complex. The vagina is short and wide, with only few transverse basal folds. The SSt is a wide and stout half ring.

Egg ( Fig. 168 ). Smooth, ovoid, wide short collar with distinct cells, similar to N. pilulifera .

DNA ( Figs. 491–492 , 494). The male holotype from Mali, a male paratype from South Sudan, and a female paratype from Guinea were sequenced for the COX1 DNA barcode fragment (holotype) and with the genome-skimming approach (paratypes). They cluster together tightly with highest support (100/100/100), and the species is maximally supported (100/100/100) as sister to a specimen of N. sp. aff. amoena ( NEOP 069). Together, they are very strongly supported (56.4/97/98) as sister to N. crustata n. sp..

Notes. The wide SSt is characteristic of female N. amoena . Differences in coloration concealed conspecificity of sexes until revealed by DNA. However, not all males are colourful, the less colourful ones are possily faded. Nemoura nigricauda ( Cameroon) and N. bella (Lake Kivu area) with similar colouration differ by a raised hump on T8 and the blunt to spatulate hemitergal callus plus penes are very different.

Etymology. The Latin adjective amoenus, pleasant, beautiful refers to the attractive appearance of some males.

Figures

FIGURE 491. Codon-model maximum likelihood phylogram based on 83 largely complete mitochondrial genome sequences only (mt-NT). Statistical support values (SH-aLRT, UFBoot) from this and other analyses summarised by squares as explained in the figure. 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. HT = holotype; PT = paratype; PCR = Polymerase Chaine Reaction; WGS = Whole Genome Shotgun.

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.

FIGURES 161–168. Neoperla amoena n. sp.. ♁ holotype: 161–163, habitus and abdominal tip (not to scale; NEOP070); 164–166, penis, only 164 to scale; ♀ paratype from Bamako: 167, 168, genital situs and egg. Scales are 100µm. bbs, bare basal stretch; tf, transverse folds; sa, spermatheca; SSt, spermathecal stalk; V, vagina.