Neoperla spaghetti, 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 : 128-130

59. Neoperla spaghetti n. sp.

( Figs. 334–339 )

Holotype ♀: Republic of Guinea Coyah [N 9.70600 W 13.38500] 4.3.1963 ( HNHM; genitalia plus eggs recovered from the abdomen, and fore body containing more eggs are mounted on separate slides Z19.61 [genitalia] & Z19.79 [body]).

Habitus. WL 11.1mm. The specimen was completely macerated, probably by decay. It is pale, except dark flagellum and tibiae. The body contains several well preserved empty eggs.

Male. Unknown.

Female ( Figs. 334–335 ). S8 with two large brown plates separated by a pale area which near the antecosta is wide and funnel-shaped but is quickly reduced to a narrow band. The plates end some distance in front of a small brown mark at the caudal segment edge. Vagina unmodified, no sclerites or spines.A narrow spermathecal stalk with sparse armature of transverse pale scales rises from concentric folds on top of the vagina and forms an exceptionally long irregular tangle of uniform width, narrowing a little only next to the spermatheca which is crumpled, shape not clearly visible.

Egg ( Figs. 336–339 ).About 300µm long, almost spherical, 37 straight striae with shallow costae and sulci. Sulci wide, irregularly punctate, microplyes freely visible. Anchor pole flat, no collar, anchor not available. Operculum wide and shallow, with distinct cells ( Figs 336–339 ).

DNA. No data.

Notes. Neoperla spaghetti n. sp. resembles N. gordius n. sp. in S8, in an unusually long spermathecal stalk, and in absence of an egg collar. Other details differ much (e.g., strong opercular cells of N. spaghetti n. sp. and the very wide base of the spermathecal stalk of N. gordius n. sp. Affinities are doubtful, by punctation of eggs the two species might belong to different groups: N. spaghetti n. sp. with irregular punctation in the N. spio subgroup, N. gordius n. sp. with bilinear micro-punctures in the N. excisa and N. sjostedti -operational complex.

Etymology. By its extreme length the tangle of the narrow spermathecal stalk resembles a dish of spaghetti; a noun in apposition.

V. The Neoperla excisa and N. sjostedti -operational complex (~ clade J, clade K + L)

Species in this operational complex were from the beginning of our work distinguished from all other species groups because:

1. known males have no unpaired medio-caudal process of T7. In many T7 is instead concave between a pair of paramedian humps,

2. females with S8 with a projecting hard nail or with a sclerite resembling a fingernail occur only in the present assemblage, and

3. egg striae have narrow sulci which lack macroscopic punctures but have micropunctures visible only in transmitted light, at magnifications ≥ 200*. They form a single regular row on each side of a sulcus and separate it from the costa. Many eggs have spiral striae with species-specific direction of spin while most other species have straight or at best oblique striae.

Unfortunately, half of the included taxa are known in only one sex, morphology did not reveal how the species are interrelated.Accordingly, the keys which rely on morphology cover the entire operational complex.Arrangement of texts follows the strong molecular evidence (except for N. multiserrata sp. n. and the exclusion of node I).

Keys to species

Males

1 T7 is flat, a trapezoidal sclerite in the middle has a wide truncate caudal edge which is opposed to and only narrowly separated from the wide, transverse top of a high process on T8 ( Figs. 373 , 386 )........................................... 2

1' T7 and T8 different, the high process on T8 with narrow top, or hook-like........................................ 3

Figures

FIGURES 334–339. Neoperla spaghetti n. sp., ♀ holotype. 334, S8 with the anterior sclerites and the pale furrow (pf, arrow) between them. For better visibility the vagina (V) with the base of the spermathecal stalk (SSt) was flipped back. The overlong SSt (Fig. 335) broke in the process, a blue line connects the fitting ends of the fragments; 336, side view of an egg; 337, oblique view of an egg operculum; 338, anchor pole view of another egg, count of costae in white script; 339, detail of striae and micropyles, enlarged from 336. Scales are 100µm, 337–339 not to scale. co, costa; mi, micropyle; sa, spermatheca; SSt, spermathecal stalk; su, sulcus, v, vagina.

FIGURES 373–385. Neoperla heideae n. sp. and N. larvata n. sp. N. heideae: 373, 374, abdominal tip and contracted penis of a misassociated paralectotype of N. excisa Klap. from Lolodorf (to the same scale), with the label in Sütterlin script; 375, contracted penis, dorsal view, 376, everted endophallus (from Libamba); 377, ♀ situs from near Kama (D. R. Congo); 378, ♀ situs (D. R. Congo, Odzala N.P., NEOP242); 379, egg (Sangmelina,Cameroon). N. larvata: 380, everted endophallus (CAR, Bayanga, NEOP240); 381, ♀ situs, sternites 8 and 9 labeled (Ghana, Ankasa Res.); 382, ♀ situs (Togo, Kati); 383, ♀ situs (Ghana, Volta R., Z21.41); 384, egg with detail, Guinea, Simbareya (NEOP237); 385, aberrant contracted penis, ♁ from Ivory Coast, Boa. The scales are 100µm; tergites, HT10 and cercus labeled. a, anchor; mi, micropyle; n, nail; sa, spermatheca; SSt, spemathecal stalk; V, vagina.

FIGURES 386–390. Neoperla sorella n. sp.: 386, 387, male holotype, abdominal tip and everted penis; 388–390, female paratype, genital situs and egg (with enlarged detail of 2 merging striae) from Bolonzo. Scales are 100µm, unless differently labelled. FIGURES 391–393. Neoperla simplex n. sp., ♀: 391, 392 genital, situs and egg of paratype from Sankuru; 393, operculum of egg of holotype from Yangambi. Figs 391 and 393 not to scale. a, anchor; mi, micropyle; n, nail; od, oviduct; sa, spermatheca; SSt, spermathecal stalk.