Leuctra ketamensis, Sanchez-Ortega & Azzouz, 1997

Zwick, Peter, Vinçon, Gilles & Figueroa, José Manuel Tierno de, 2014, Morphology And Systematic Position Of Two Leuctra Species (Plecoptera: Leuctridae) Believed To Have No Specilla, Illiesia 10 (5), pp. 43-51 : 46-49

Leuctra ketamensis Sánchez- Ortega & Azzouz 1997

( Figs. 9–12 , 14–16 )

Material examined. Holotype: 1♂, Achraf Stream , 4 km of Tlata Ketama, 1400m, Al-Hoceïma, Rif, Morocco, 34°53'30"N, 4°35'50"W, 23-10-1993. Paratypes: 1♀, Achraf Stream , 4 km of Tlata Ketama , 1400m, Al-Hoceïma, Rif, Morocco, 34°53'30"N, 4°35'50"W, 29-10-1993; idem , 3♀, 23-10-1994. 1♀, Oued Ketama , Tlata Ketama , 1210m, Al-Hoceïma, Rif, Morocco, 34°50'15"N, 4°34'10"W, 29-10-1993. The specimens remain in the Sánchez- Ortega collection (University of Granada, Spain). Other material: 1♀, Ketama, above Azila, Tidirhine Mount, 1600m, Al- Hoceïma , Rif, Morocco, 13-11-2013 . 1♂, SW Tazzeka Mount, below Bab Taka Pass, Oued el Abod tributary, 1400m, Taza , Middle-Atlas, Morocco, 13- 11-2013, Vinçon leg.

Habitus. Typical of Leuctra except that in the male the maxillary palpus is a little longer than usual.

Male terminalia ( Figs. 9–15 ). Tergite V with bellshaped median membranous area. Tergite VI with entire anterior margin and a pair of strongly sclerotized processes; each process having two teeth, a small one, hook-shaped, on the internal side, and a long one extending posteriorly on half tergite VII, and ending in two sharp points ( Fig. 9 ). Tergites VII and VIII without sclerotized process, but with central dark pigmented area connected to the anterior margin. Sternite IX (SIX) with parabolic caudal margin, largely soft, only a mediobasal strip and caudally narrowing lateral stripes sclerotized and dark, without ventral vesicle ( Fig. 10 ). No connection to the structures which (by comparison with L. bidula ) are the paraprocts. They are located high up above SIX, pointing forward and upward ( Figs. 9, 11, 12 , 14, 15 ).

Tergite X dorsally similar to other Leuctra species , except that the basal strip of the epiproct is strongly sclerotized ( Figs. 9 , 15 ). The ventrolateral sclerite brackets formed by TX not separated from the paraprocts by sutures. The brackets curve up, each supports a very long spine (lp) whose widely separated and slightly diverging apices lie alongside the epiproct ( Figs. 11, 12 , 14, 15 ). Caudally, the brackets connecting TX and paraprocts curve inward, almost meeting medially. They support a large sclerotized basal cone (bc) high above sternite IX. Caudo-medially the cone is divided, each side supports a vertical outgrowth. It is in side view divided into a straight long process (dp1) and above it a shorter process with curved upper contour (dp2) ( Figs. 11 , 14 ). In dorsal view, the longer processes (dp1) are contiguous, with a delicate anterior suture. The shorter processes (dp2) are widely separate ( Figs. 12 , 15 ).

Between the halves of the basal cone (bc) and beneath its dorsal processes projects a short median tube which represents the seemingly missing specilla (sp) ( Figs. 11 , 14, 15 ). At 630x, its paired caudal openings are visible. By transparency the tube can be seen reaching far into the body ( Figs. 14, 15 ). It arises from a typical attachment bulb into which the common gonoduct enters from below. In ventral view (not shown) the tube with the paired sperm ducts was obscured by some longitudinal sclerotization which in side view appeared like a ventromedian crest. This may be rudiments of the median components of the paraprocts, details not visible. Cerci short and truncated.

Female terminalia ( Fig. 13 ). Sternite VII strongly sclerotized, with posterior edge terminating in two lobes overlapping anterior margin of sternite VIII. Sternite VIII: subgenital plate split into two parts by wide central membranous field; each lateral part is split into two lobes; the inner one oriented towards the central part of the sternite, the outer one nearly parallel to the segment side and almost twice longer than the inner one ( Fig. 13 ). Cerci short and truncated.

Ecology and distribution. Crenophilic species restricted to the highest points of the Rif and to the northern part of the Middle Atlas close to Taza (1250– 1600m) ( Fig. 16 ). The adults emerge in autumn (X–XI).

Figures

Figs. 9–13. Leuctra ketamensis. Male abdomen: 9, Dorsal. 10, Ventral, sternite IX;.11, Paraprocts, dorsal. 12, Paraprocts, lateral. Female abdomen: 13, Ventral, showing the pregenital and subgenital plates (13 from Sanchez-Ortéga & Assouz, 1997).

Figs. 14, 15. Leuctra ketamensis, male. 14, Terminal section of segment X and paraprocts in lateral view. 15, dorsal view of part of TIX and TX. Both to same scale, abbreviations as in Figs. 5–8, plus: bc, basal cone; dp1, dp2, dorsal paraproct processes 1 and 2; ic, insertion of cercus.

Fig. 16. Geographical distribution of Leuctra bidula and L. ketamensis.

Figs. 5–8. Leuctra bidula, male. Segments IX and X, shown as transparent: 5, Lateral. 6, Oblique caudal view; open arrow in Fig. 5 indicates direction of view. 7, Dorsal. 8, Ventral. All to the same scale, semidiagrammatic: a, articulation; ab, attachment bulb; c, cercus and cercus attachment site, respectively; e, epiproct; ip, invaginated ventral portion of paraproct; lp1, lp2, lateral processes 1 and 2, respectively; os, open space; SIX, TIX,TX, sternites and tergites IX and X, respectively; sp, specilla with sperm ducts.