Neoperla spio ( Newman, 1839 )

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 : 103-106

45. Neoperla spio ( Newman, 1839)

( Figs. 238–249 )

Chloroperla spio Newman, 1839 , Mag. nat. Hist. 3: 86. Perla spio — Pictet 1842: 282.

Neoperla spio — Needham 1920: 36.

Neoperla spio —Needham 1940: 166.

Neoperla spio —Hynes 1952: 104 (partim).

Neoperla spio — Illies 1966: 277 (partim).

Not Neoperla spio — Zwick 1976a: 687, figs 1, 5.

Type material studied: Republic of Sierra Leone, Chloroperla spio , J holotype: Sierra Leone (pinned, terminalia mounted on pinned slide by P. Zwick, BMNH) .

Additional material studied: Republic of Ghana, 1♁ ( NEOP190 ) , 1♀ ( NEOP191 ) : Subri R. 05.11.1993 light trap; NUFU project (slide GH.02-11); 4♁ ( NEOP193 , SMNS; NEOP194 , ZMBN) : Ghana, Volta Region, Wli Falls, Afegame , St. 6, 11.03.1993 J.S.Amakye & J. Kjaerendsen light trap; NUFU-project ZMBN Sample no. 1; 1♁ ( NEOP192 ) : Ghana, Volta Region, Wli Falls, Afegame , St. 10, 08.03.1993 J.S.Amakye & J. Kjaerendsen light trap; NUFU-project ZMBN Sample no. 1 (in ETOH; ZMBN) . 3♀, Ghana Volta Region, Wli Falls, Afegame , St. 6 11.03.1993 J.S.Amakye & J. Kjaerendsen light trap; NUFU-project ZMBN Sample no. 1 (Slides 98/8, 98/12, 98/ 13 in SMNS, bodies lost) .

Habitus. WL 9.5 (holotype)– 10.5 mm. Yellowish ochre, no pattern, ocelli in a brownish spot.

Male ( Figs. 238–243 ). Antecosta T7 with an extension supporting a short transverse sclerite ( Fig. 238 ). An approximately rectangular posterior sclerite with angular front corners ends in a pyramidal process. The Y-shaped sclerite on T8 is caudally band-like, narrow, with a forward-inclined hump near midlength ( Fig. 239 ). Several SB on the front of the hump stand opposite some SB on a vertical keel on the rear face of T7. T9 unmodified, with median furrow between pilose paramedian swellings. Floor of furrow sclerotised, sclerite reaching back to near the small heart-shaped epiproct. HT10 downcurved in side view, in dorsal view straight, narrowing distally, then again wider, tip truncate. Hemitergal callus tongue-shaped.

Penis sclerotised, tubular, dorsal face slightly concave ( Figs. 240–241 ) and with fine external triangular asperities (line connecting Figs. 242–243 ). Apical membrane dorsally bare, ventrally with two groups of spines raised like spine cushions when turgid, spines pointing basad. Endophallus over twice as long as the penis but much narrower than the penis tube, the armature begins with small unordered spines, further distally spines stand in rows, initially there are fine needles, more distally larger needles stand opposite slender cones ( Fig. 243 ). Near midlength, long conical spines larger than those at the penis apex stand in a single row, size decreases distally.

Female ( Figs. 244–246 ).—Two brown marks on S8 are separated by a pale transverse angle ( Fig. 244 ). Vagina unmodified, small spine patches occur laterally from the attachment of SSt. SSt narrow, more than three rings long, of uniform width, but the internal spine band is very narrow from base to near midlength ( Fig. 244 ), distally the entire diameter is scaly. Scales resemble groups of shark teeth ( Fig. 246 ) more than a dense spine carpet (as shown in Fig. 113 ). The spermatheca is curled.

Egg ( Figs. 247–249 ). Slender ovoid with wide poles, 364–374µm long, average size 367*194µm. Collar sessile, with one ring of cells, the anchor cavity is shallow, the anchor mushroom-shaped with solid stem. Operculum broadly rounded, with dense unordered punctures. Only 11 straight striae, costae bare, raised little ( Fig. 249 ). Sulci with dense unordered fine punctures a little larger than those on the operculum. Micropyles (pointer in Fig. 248 ) are freely visible.

DNA ( Figs. 492 , 496 ). A total of five specimens from Cameroon were sequenced for the COX1 DNA barcode fragment, representing the core geographic distribution of this species and providing near maximum support (99.8/100/100) for the monophyly of the species. The species is very strongly supported (89.3/99/100) as sister to N. beta n. sp. + N. burgeoni Navás / N. sassandrae n. sp.. Both sexes are represented.

Notes. Details of the endophallus are not visible in the holotype. The present description is based on subjectively identified fresh specimens from Ghana. Neoperla bella also has external asperities on the penis and a narrow long endophallus, and was therefore mistaken for N. spio by Zwick (1976). The two are easily distinguished (e.g., by the angular front corners of the sclerite on T7 of N. spio , and by the spatulate processes of HT 10 in N. bella ). Other than suggested by Hynes (1952) and generally accepted for decades, N. spio is not variable and widespread but is restricted to West Africa and apparently not common.

The SSt of N. primitiva Geijskes, 1952 from Sumatra is very similar. Small scales of similar shape occur in the terminal section of the SSt of several African species (e.g., in the N. dubia -group and in N. burgeoni but basal scales form a dense cover resembling Fig. 108 ).

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 238–243. Neoperla spio (Newman), ♁: 238–241, holotype: abdominal tip in dorsal and lateral views, penis in ventral and lateral views, endophallus partly everted (not to scale); 242, ♁ from Ghana, cleared penis in lateral view (the scale is 100µm); 243, enlarged ventral view of another Ghanaan specimen.

FIGURES 244–249. Neoperla spio (Newman), ♀ and egg from Ghana, Subri R.: 244–245, genital situs and detail of vaginal spines; 246, detail of spines in spermathecal stalk (SSt); 247, egg, 248 detail of chorion, arrow indicates micropyle; 249, optical cross section of egg (from a photograph). Scales are 100µm, unless differently indicated. co,costa; sa, spermatheca; sp, spicules; SSt, spermathecal stalk; su, sulcus; 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.