Neoperla nichollsi, 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 : 83

34. Neoperla nichollsi n. sp.

( Figs. 188–192 )

Type material: Republic of Liberia, 8 mi NW Belefuanai , S fork S.Paul R., 11.8.66, Ross & Lorenzen ♀ Holotypus ( CASENT 8413120 , Slide Z 19.34 ( NEOP057 ), 6♀ paratypes ( CASENT 8413121 , CAS & SMNS slides Z19.31 & 33, Z19.97-101).

Habitus. Same as other group members, colour light ochre, wings a little infuscate. WL 10.5–11.2mm.

Male. Unknown.

Female ( Fig. 188 ). S8 without pattern, middle of caudal edge bare, firm, shallowly concave. Vagina very long, of uniform width, base with transverse folds, a dense pile of circular folds on top ( Fig. 188 ). The coiled SSt forms about 3/4 of a circle and is membranous along the entire concave side. Spermatheca spiral.

Egg ( Figs. 189–190 ). Regular and oval, 289*237*µm, plus 42.5µm for the narrow collar with flared scalloped rim ( Figs. 189–190 ). The thin anchor stem occupies only a small fraction of available space inside collar, the cap is very delicate, edge with some short finger-shaped extensions each supporting a strongly light refracting body.

DNA ( Figs. 491–492 , 494). Only the female holotype from Liberia was sequenced with the genome-skimming approach, resulting in 10,992bp of mitochondrial, protein-coding genes. This species is very strongly supported (92.5/97/98) as sister to N. occulta n. sp .

Notes. The long transversely folded base of vagina and the many circular folds around its top are distinctive, the oval eggs with overlong collar are also characteristic. Marginal outgrowths of the cap occur in many Perloidea, certainly also among other Neoperla spp. , but they are often abraided.

In species with striate eggs, striae occasionally fork and merge with neighbouring striae, other anomalies of eggs are rare. One N. nichollsi sp. n. female had, in addition to normal eggs, a few malformed ones without collar but with a thick stem projecting from an oblique anchor cavity and irregular chitinous bodies under the cap ( Figs. 191–192 ).

Etymology. The name honours James Nicholls (CSIRO), for his great contribution of building most DNA sequence libraries for genome skimming.

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 181–192. ♀♀ of the Neoperla pilulifera-complex. N. pilulifera n. sp.: 181, genital situs, ♀ from Ghana, Ankasa Reservation; 182, egg of same, arrows show micropyles; 183, 184, collar and micropyle of ♀ from Gabun, Belinga; 185, “teleskoping” collar of ♀ from Schouteden, Koteh / Belinga. N. occulta n. sp.: 186, 187, genital situs and egg, Central African Republic, Bayanga. N. nichollsi n. sp., 188–192: 188, 189, genital situs and egg (Liberia, 8 mi NW Belefuanai, S fork S.Paul R., 11.8.66, Ross & Lorenzen diagrammatic, from photographs) (NEOP057); 190–192 are anchor pole regions of an intact and of 2 teratological eggs, all from the same ♀. In 186–188 ♀ situs and eggs to the same scales, respectively. The scale in 181 is 100µm, others figures as indicated, or not to scale. a, anchor; od, oviduct; rd, receptacular duct; sa, spermatheca; SSt, spermathecal stalk.