Madenemura andringitrensis Paulian, 1959

Zwick, Peter, 2015, Notes on Madagascan Stoneflies (Plecoptera: Notonemouridae), Zootaxa 4059 (1), pp. 169-180 : 172-176

Madenemura andringitrensis Paulian, 1959

( Figs. 3–9 , 18, 19 , 25, 26 )

= Madanemura perrieri Paulian, 1959 , new synonymy. = Madanemura sp. 2 ♂ of Paulian (1959).

Material studied. Madagascar, Ranomafana National Pk., Mariavaratra stream, 2115.629'S, 4725.149'E; emergence trap, J. Benstead, 1997-1998, 61♂♂, 54♀♀; the seasonal distribution is shown in Fig. 26 . Prov. Fianarantsoa, 7km W Ranomanfana, 900m, W.E.Steiner (~ 22.223°S, 46.929°E; all USNM): Malaise trap in small clearing, 20– 31.01 .1990, 2♂, 1♀; 01.– 07.03.1990, 1♂; at black light: 20– 31.01.1990, 1♀; 17.– 22.02.1990, 1♂, 1♀; 01.– 0 7.03.1990, 1♂; Malaise trap across stream montane rain forest, 20.– 24.03.1990, 3♀; 08.– 13.03.1990, 1♀.

Larvae, probably M. andringitrensis : Madagascar, Ranomafana National Pk., Mariavaratra stream, 2115.629'S, 4725.149'E, J.P.Benstead, 8-19-98, 15 larvae; Madagascar, Ranomafana N.P. E4725.458' S2116.040' 26 Oct 1998 B, 3 larvae; Madagascar, Ranomafana N.P. 4725.149'E 2115.629'S, 26 Oct 1998, A, 3 larvae; Tolongoina stream, nr. Ranomafana N. P. Madagascar S2115.417' E4727.440' 7-2-98 J.P.Benstead, 1 last instar larva; Fompohonona stream, Ranomafana N.P., Madagascar S2116.040' E4725.458' 6-15-98 J.P. Benstead, ca. 10 larvae; same site, 8- 19-98 J.P. Benstead, 4 larvae; Vatoharanana stream, Ranomafana N.P., Madagascar S2117.407' E4725.677' 6-29-98 J.P. Benstead, 2 larvae (all USNM).

Habitus. As for the genus; WL of males 6.3–7.4mm, of females 7.7–9.5mm. Wing length varies with time ( Fig. 25 ).

Male. Tergite 10 longitudinally divided by a pale hairless median zone which is wide in front and narrows as it continues onto the baseplate of the epiproct where it tapers. Baseplate of epiproct separated from T10 by a narrow transverse pale and hairless line. The plate is almost parabolic, wide in front, narrowing backwards, a transverse strip in front of the short truncate caudal edge is beset with small black spinules. The sclerites supporting the epiproct originate on the underside of the baseplate, in cleared specimens their edges can be seen by transparency. Together they form the wide peduncle of the narrow erect hook-like part of the epiproct. Its apex is triangular, with blunt tip ( Fig. 7 ). In side view the spinulose area of the baseplate appears as a shallow bulge over which the epiproct curves ( Fig. 8 ).

The paraproct body ( Fig. 9 ) is stout, about twice as long as wide and about half as long as the ventral lobe of S9. Its rounded front end includes a median sclerotised structure which in side view appears like a blunt, forwardcurved tube. The sides of the paraproct are elongate lobes with large circular sensilla, mainly on the outside. The apical portion bears numerous straight setae. Along the ventral edge (lying medially in slide mounts) is an elongate sclerite which is wide in the basal third, but caudally grows narrower and curves towards the medial edge.

Female. The ovipositor is very short, extending only to the base of the paraprocts ( Figs. 5, 6 ). S8 is caudally extended, triangular, slightly raised along the midline, the end soft and projecting as a blunt knob. The wide, medially excised base of S9 is concealed by S8, caudally it projects as a broad flat process with a central soft pale area surrounded by a fairly wide sclerite with fine pilosity. The postgenital plate extends a little beyond the short subgenital plate of S8.

Notes. I recognize the species by the unusually short and wide ovipositor which looks “fleshy”, a term used by Paulian (1959) only in the description of M. andringitrensis . The small illustration of M. sp. 2 ♂ of Paulian (1959) fits the present males. Eighty-nine percent of the emergence trap catches belong to this species, the sex rate is balanced (53% males; Fig. 26 ), the conspecificity of sexes is beyond doubt. See the notes on Ecology below.

Paulian (1959) apparently noticed some terminal annulation around the rudimentary end segment of the female cercus and considered it was plurisegmented. However, such subterminal annulation occurs occasionally in many Nemouroidea and concerns only the pilosity. This annulation and differences in the posture of the ovipositor were used to distinguish M. perrieri which I regard as conspecific. The nominal taxa in question were all taken in the same geographic area, roughly between 21.26°S / 47.42°E and 22.22°S / 46.93°E.

Figures

FIGURES 1 – 9. Madenemura spp. 1, Madenemura sp., wings, after a photograph; 2, M. culminalis, male abdominal tip, lateral; 3 – 9, M. andringitrensis: 3, detached and opened ventral portion of abdominal segment 9, oblique dorsal view; 4, the detached paraproct body with the retractor muscles; 5, female sternite 8 plus 9, in situ; 6, female sternite 9, detached; 7, dorsal view of center of male T 10 with epiproct; 8, caudal part of baseplate and hook of epiproct in side view; 9, the isolated paraproct body, dorsal view. 3 and 4 not to scale, 5, 6 and 7, 8 to the same scale, respectively. bb, basal bar; bp, epiproct baseplate; ce, cercus; gp, gonopore; mu, muscles; pb, paraproct body; rm, retractor muscle; S, T, sternite and tergite, respectively, with number of corresponding segment; sd, sperm duct; sp, sperm pump; vl, ventral lobe.

FIGURES 18 – 24, Madenemura spp., female abdominal tips, in lateral (even numbers) and ventral (uneven numbers) view; after photographs, semidiagrammatic: 18, 19: M. andringitrensis. 20, 21: M. descarpentriesi. 22, 23: M. culminalis; 24: M. pauliani sp. n. (holotype). Same scale for all.

FIGURES 25, 26: Madenemura andringitrensis, emergence trap collections on Mariavaratra stream. 25, variation of front wing length over time; 26, number of males and females taken per month. The abscissa is the same for both diagrams.