Mesophylax isly Ibrahimi, Taybi & Mabrouki, 2024

Taybi, Abdelkhaleq Fouzi, Mabrouki, Youness & Ibrahimi, Halil, 2024, Description of Mesophylax isly sp. nov. (Trichoptera, Limnephilidae) from Morocco, and new genus records from the Balkans, Zootaxa 5492 (2), pp. 279-288 : 282-284

Mesophylax isly Ibrahimi, Taybi & Mabrouki sp. nov.

( Figures 2–6 , 7–11 )

Type material. Holotype (male): Morocco, Eastern Region , Aval Oued, Isly River, 34.6094°N, 1.8602°W, 454 m a.s.l., 03.vi.2018, leg. Y. Mabrouki and A. F. Taybi. Paratypes (3 males, 2 females): with the same label data as the holotype .

Distribution. Morocco, Eastern Region, Isly River.

Diagnosis. The male of the new species is most similar to that of Mesophylax aspersus hoggarensis and differs mainly in exhibiting (1) high, broad inferior appendages, higher than intermediate appendages, each with generally straight inner and outer margins in lateral view; (2) apically longer than basally inferior appendages in ventral view; (3) apically placed inner lobes of inferior appendages in ventro-caudal view; (4) thick parameres in ventro-caudal view; (5) shallow axillary fossa of inferior appendages. The M. a. hoggarensis male has (1) low, narrow inferior appendages, lower than intermediate appendages, each with sinuate inner and outer margins in lateral view; (2) inferior appendages basally longer than apically in ventrocaudal view; (3) mesally placed inner lobes of inferior appendages in ventrocaudal view; (4) slender parameres in ventrocaudal view; (5) deep axillary fossae of inferior appendages. In addition, males of M. isly sp. nov. are distinguished from those of M. a. hoggarensis by their more curved and shorter parameres in lateral view.

The female of Mesophylax isly sp. nov. is most similar to that of M. a. hoggarensis from which it differs by exhibiting (1) a downward-arching, apically blunt segment X in lateral view; (2) a short, apically rounded supragenital plate in lateral view; (3) an apically bipartite mesal lobe of the vulvar scale in ventral view; and (4) apically rounded, small lateral shoulders of segment IX in lateral view. The female of M. a. hoggarensis has (1) a mesad-arching, apically tapering segment X in lateral view; (2) a long, rounded supragenital plate in lateral view; (3) a unipartite, apically slightly convex mesal lobe of the vulvar scale in ventral view; and (4) apically acuminate, large lateral shoulders of segment IX in lateral view.

Description. General appearance. Habitus brown, sclerites and tergites dark brown; cephalic and thoracic setal areas pale; cephalic, thoracic, and abdominal setation blonde; legs brown to fawn, with darker areas; wings brown with darker nuances, with fine blonde setae. Length of each forewing 14.5 mm (holotype), 14.5–16.0 mm (n = 4). Male spur formula 0,2,2; female spur formula 1,2,2.

Male genitalia. Segment IX fused with basal parts of inferior appendages, with narrow acuminate dorsal portion and longer ventral portion, laterally even longer, convex anteriorly, in lateral view. Superior appendages apically bipartite with round ends in lateral view. Intermediate appendages wide basally, tapering apically, downward arching in lateral view. Free parts of inferior appendages broad, triangular, acute apically, each with posterior edge notched basally in lateral view. Inner lobe of free part of each inferior appendage visible in lateral view as small subapical triangle; in ventral view broadly quadratic, blunt dorsoapically, elongate, acute ventroapically. Phallic apparatus consisting of simple aedeagus and pair of parameres; in ventral view parameres broader basally, acute apices as high as tip of aedeagus.

Female genitalia. Segment IX setation abundant, more abundant in the dorsal half and along the lateral margins. Segment X triangular in lateral view, blunt apically in dorsal view; in ventral view wide along basal half and parallelsided apically. Supragenital plate apically round in lateral view, shorter than segment X; vulvar scale even shorter, elongate, subtriangular. Lateral shoulders of segment IX membranous, with sclerotized edges, long ventrally, short dorsally, generally triangular, turned mesad posteriorly.

Larva and pupa. Unknown.

Etymology. The species epithet “isly ” refers to the Isly River, where the new species was discovered, and, in the Amazigh language, it translates to “new groom.”

Habitat. The new species was found in one of the permanent tributaries of the Isly River (south of Oujda City), in a location known as Tayret. The river exhibits irregular flow patterns closely tied to rainfall, experiencing floods from autumn to spring and severe summer low flows nearly year-round. The intense sunlight fosters the growth of perilithon, filamentous algae, and green algae ( Characeae ). The sediment in the springs consists of blocks, stones, pebbles, sand, and occasionally mud. The vegetation along the banks is sparse, predominantly comprising reeds ( Arundo donax L.), juncus (Juncus acutus L.), and occasionally typha ( Typha latifolia L.).

The habitat of the new species is populated by various benthic macroinvertebrates, including dragonflies such as Crocothemis erythraea (Brullé 1832) , Trithemis annulata (Palisotde Beauvois 1807) , Orthetrum cancellatum (Linnaeus 1758) (in both larval and adult stages); aquatic Hemiptera such as Naucoris maculatus Fabricius 1798 , and Notonecta glauca Linnaeus 1758 ; aquatic coleopterans including Agabus nebulosus (Forster 1771) ; mayflies like Cloeon dipterum (Linnaeus 1761) and Caenis luctuosa (Burmeister 1839) , as well as dipteran larvae (e.g., Chironomidae ). Additionally, two aquatic vertebrates have been observed in the habitat: Pelophylax saharicus (Hartert 1913) and Mauremys leprosa (Schweigger 1812) , both widely distributed in the region.

Mesophylax isly sp. nov. seems to require habitats with good water quality. The analysis of the physicochemical parameters of the water (ammonium and BOD 5) showed a good environmental quality of the water, according to the Moroccan surface water guidelines of good quality ( Table 1 ). However, because it is located in an arid rural and agricultural environment, the habitat is disturbed by human activities, particularly water abstraction in summer, as is the case throughout the eastern region of Morocco ( Mabrouki et al. 2018, Taybi et al. 2018).

Figures

FIGURES 2–6. Male and female genitalia of Mesophylax isly sp. nov. 2–4, male genitalia: 2, left lateral; 3, ventrocaudal; 4, dorsal; 5, 6, female genitalia: 5, left lateral; 6, ventral. Scale bar = 1 mm. ae = aedeagus; af = axillary fossa (paired); ia = intermediate appendage (paired); ifa = inferior appendage (paired); il-ifa = inner lobe of an inferior appendage; ll = lateral lobe (paired) of vulvar scale; lsh = lateral shoulder of segment IX (paired); ml = mesal lobe of vulvar scale; pa = paramere (paired); sa = superior appendage (paired); sIX = segment IX; sp = supragenital plate; sVIII = segment VIII; sX = segment X; vs = vulvar scale.

FIGURES 7–11. Photos of genitalia of Mesophylax aspersus aspersus Rambur 1842, Mesophylax impunctatus aduncus Navás 1923 and Mesophylax isly sp. nov. 7, M. a. aspersus from Guenfouda, Morocco, male, left lateral; 8, M. i. aduncus from Ballgjaj, Albania, male, left lateral; 9, M. isly sp. nov., male, left lateral; 10, M. isly sp. nov., female, left lateral; 11, Parameres (paired) and aedeagus of M. isly sp. nov., left lateral. Scale bar = 1 mm.