Neoperla funiculata, 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 : 108-110

47. Neoperla funiculata n. sp.

( Figs. 258–266 )

Type material. Democratic Republic of the Congo, ♁ Holotype: B.Congo, Lwiru R., 47km N Bukavu [-2.49, 28.84], 1950m, XII.15-57 Ross & Leech leg. ( CASENT 8413040 ; slide Z.18.27, penis everted). 1♀, 1♁ paratypes, Democratic Republic of the Congo, emergence trap on stream Kalengo [~ 2.2°S, 28.7°E], near Institut pour la Recherche Scientifique en Afrique Centrale at Lwiro, 10km W of Lake Kivu, 1750–1800m, K. B̂ttger, April 1972 ( SMNS).

Habitus. WL ♁ 12.5mm, ♀ 16.2mm. Rs with 4–5 branches. Ochre, wings faintly infuscate. Ocelli separate by their own diameter, a little more in the female, on an anteriorly pointed dark spot. Frontoclypeus light brown, laterally with two regular yellow arches, medially with a dark triangle. Antenna dark. Legs ochre, subgenual organ dark. Fore tibia dark grey, middle tibia less, hind tibia least distinctly infuscated. Cercus base yellow, remainder missing.

Male ( Figs. 258–263 ). Sternites unmodified. A narrow triangular process with some SB on its rear face rises from a large approximately rectangular sclerite on T7. Sclerite on T8 Y-shaped, very wide in front, raised as a hump, caudally a narrow strip. T9 unmodified. Process of HT10 stout, angularly bent in dorsal view, straight in side view, apex abruptly pointed. Mediobasal callus plump, broadly rounded.

Penis a soft straight slightly waisted tube. Apex membranous, with a few appressed spines caudally from which commences the narrow rope-like endophallus which is about twice as long as the penis. Armature consisting of small remarkably slender spines, initially in three, distally in two regular rows. A thin cuticular tube runs back into the penis from the endophallus tip.

Female ( Fig. 264 ). S8 with large transverse brown patch surrounding a pale anchor-shaped mark, caudal margin with wide transverse shallow notch. Vagina slender, dense anterolateral spine patches laterally from attachment of SSt. The spermathecal coil is ~3 rings long, uniformly narrow and densely spinulose, except a short bare basal stretch on the concave side. Scales form a dense inner carpet.

Egg ( Figs 265–266 ). 400*220µm, spindle-shaped, both poles narrow and of similar width. Collar rim-like, ~30 straight striae extend from it to a few cells on the small top of operculum ( Fig. 265 ). Anchor mushroom-shaped, with firm undivided stem, anchor cavity bowl-like. Costae and sulci of similar width, impunctate ( Fig. 266 ), but every second structure looks like being spongy and has some weak median line. Also, under certain oblique views a row of mini-micropunctures is visible on each side. The same stripes lie minimally higher than the completely smooth sulci in which unmodified micropyles are freely visible.

DNA. No data.

Notes. Narrow tubular endophalli with regular rows of delicate spines are characteristic of species near N. spio (e.g., N. bella n. sp., N. biserrata , n. sp., and N. nigricauda ). Species differ in details of male and female genitalia and eggs.

Neoperla funiculata n. sp. is most similar to N. bella n. sp.. Males differ by the bent and pointed (as opposed to straight and spatulate) hemitergal process, a few terminal external spines on the penis, and an even longer endophallus with only slender sharply pointed spines. Females have a regular anchor-pattern on S8 and a very long and narrow spermathecal stalk. Neoperla funiculata n. sp. eggs are unusual in that sulci and costae are both wide and separated by a single line of micro-punctures.A sulcus is identified as such by the presence of a micropyle. Neoperla filamentosa and N. spironema have similar eggs but in them the sulcus is additionally raised as a secondary costa, with the micropyle on top ( Fig. 312 ).

Etymology. The Latin adjective, funiculatus, provided with a thin rope, alludes to the endophallus shape.

Figures

FIGURES 258–266. Neoperla funiculata n. sp.: ♁ holotype 258, 259, ♁ abdominal tip, dorsal and lateral; not to scale; 260, apex of penis with incompletely everted endophallus; 261, enlarged apex of endophallus; note that it contains 2 more rows of un-everted spines. Paratypes from Kalengo stream, D. R. Congo: 262, 263, contracted penis in lateral and dorsal views; 264, ♀ genital situs, vagina flipped back to expose pattern on S8; 265, SEM-micrograph of egg (courtesy of MPI for Limnology, Pl̂n); 266, detail of chorion. Unless differently indicated, scale lines are 100µm, other figures not to scale. FIGURES 267–271. Neoperla biserrata n. sp., male holotype. 267, 268, cleared abdominal tip in oblique dorsal and lateral views, not to scale; 269, 270, contracted penis in dorsal, lateral, and ventral views, scale line is 500µm; 271, detail of endophallus near base. Tergites, HT10 and cercus are labeled. co, costa; mi, micropyle; sa, spermatheca; SSt, spermathecal stalk; su, sulcus; V, vagina.

FIGURES 309–312. Neoperla spironema n. sp.: 309, 310, holotype; 311, a paratype; both from Ankasa Game. Res; 312, SEMdetail of chorion with the 2 kinds of costae and a micropyle (Ivory Coast, USNM; from Moore, 1991). Scales are 100µm, or as indicated. mi, micropyle; sa, spermatheca; SSt, spermathecal stalk; V, vagina.