Orthomus lacouri (Antoine, 1941)

Serrano, J., 2021, The genus Orthomus Chaudoir, 1838 in the Iberian Peninsula and Morocco, Russian Entomological Journal 30 (4), pp. 430-447 : 439-441

Orthomus lacouri (Antoine, 1941)

Figs 56–64.

According to Pupier and Coulon [2013] this species includes different geographic races that are distinguished by morphological features, and thus deserve their ranking as subspecies. Three of them are found in NE Morocco, Orthomus lacouri lacouri (Antoine, 1941) ; O. lacouri haroldi Pupier et Coulon, 2013 , and O. lacouri kocheri Mateu, 1955 . The fourth subspecies, O. lacouri pupieri Jeanne, 1988 , is proper of NW Algeria. Here I follow the taxa descriptions published by Pupier and Coulon [2013] and Chavanon et al. [2016], together with personal observations of material of this species deposited in the MNCN Madrid and DZAFUM. Male genitalia are the key characters that distinguish the subspecies, which share in common most external characters. Thus, a general description follows and peculiarities of the subspecies are indicated below.

Dorsum from black to piceous brown, appendages brown. Body length 10.5–11.3 mm. Eye of moderate size and convex, tempora oblique. Males shiny, females shiny or somewhat dull with visible microreticulation (O. l. lacouri ); both sexes of O. l. kocheri show a dull dorsum.

Pronotum shape trapezoid, anterior angle briefly protruding ahead except for O. lacouri haroldi , anterior basis moderately concave; side arcuate, more narrowed forward, slightly narrowed backward and showing maximum width near posterior basis (Fig. 56); posterior angle slightly obtuse and without tooth; basis no or slightly (O. l. haroldi) emarginate; inner fovea linear and marked, outer fovea poorly impressed; basis with points varying between scarce and moderately dense.

Elytra parallel, humeral tooth vestigial, striae punctured with variable intensity; discal pores on stria 3; 8th interval almost vertically tumbling down to elytron margin.

Prosternal process truncate; metepisterna long, smooth and narrowed backward (Fig. 57); ventrites almost smooth, with fine punctures except for O. lacouri kocheri , that shows well-marked punctures; male mesotibia distally dilated, metatibia with marked crenulation in inner side of distal half.

Female genitalia (Fig. 58) with a short spermatic conduct followed by a progressively widened spermatheca of moderate length [ Pupier, Coulon, 2013].

According to the detailed study of Chavanon et al. [2016], each subspecies has a “typical” shape of the median

57 56 62 63 64 58

Figs 51–64. Orthomus spp : 51–55 — O. abacoides ; 56–64 — O. lacouri (56–57, 63 — O. l. kocheri (56 — female); 58–60, 62, 64 — O. l. haroldi; 61 — O. l. pupieri); 51, 56 — habitus; 57 — metepisterna; 52 — punctures of abdominal segments; 53, 59 — median lobe of aedeagus; 54, 61–64 — apex of median lobe of aedeagus; 55, 58 — genitalia of female; 51, 54, 56, 61–64 — dorsal view; 57–58, 60 — right lateral view; 53, 59 — left lateral view; 52 — ventral view; 51 — reservoir El Fakia, Algerie; 55, 61 — Sidi Daho ez Zahir, Algerie; 58 — Jebel Tikermine, Morocco; 62 — Tannezatte, Morocco; 63 — Farkhana, Nador, Morocco; 64 — Sidi Bouhouria, Berkane, Morocco; 53–55, 58–61 — after Pupier, Coulon [2013]; 62–64 — after Chavanon et al. [2016]. Scale bars: 1.5 mm (Fig. 51); 1.6 mm (Fig. 56).

Figs 51–64. Orthomus spp : 51–55 — O. abacoides ; 56–64 — O. lacouri (56–57, 63 — O. l. kocheri (56 — самка); 58–60, 62, 64 — O. l. haroldi; 61 — O. l. pupieri); 51, 56 — внеШний вид; 57 — Эпистерн Заднегруди; 52 — пунктировка сегментов брюШка; 53, 59 — среднЯЯ долЯ Эдеагуса; 54, 61–64 — верШина средней доли Эдеагуса; 55, 58 — гениталии самки; 51, 54, 56, 61–64 — сверху; 57–58, 60 — сбоку справа; 53, 59 — сбоку слева; 52 — сниЗу; 51 — водохранилиЩе Эль- ФакиЯ, Алжир; 55, 61 — Сиди Дахо ЭЗ Захир, Алжир; 58 — Джебель Тикермин, Марокко; 62 — ТаннеЗатт, Марокко; 63 — Фархана, Надор, Марокко; 64 — Сиди БухуриЯ, Беркане, Марокко; 53–55, 58–61 — по Pupier, Coulon [2013]; 62–64 — по Chavanon et al. [2016]. МасШтаб: 1,5 мм (Рис. 51); 1,6 мм (Рис. 56).

lobe of aedeagus, but this shape may vary notably depending on the degree of population gene flow, that results in “hybrid” shapes intermediate between those of “typical” exemplars. That paper should be consulted to check the variability; here I shall refer to the so-called “typical” shapes.

In lateral view the distal half of the median lobe of aedeagus is almost straight in O. l. kocheri, sinuate in O. l. haroldi and O. l. lacouri , and is ventrally bent in O. l. pupieri [ Pupier, Coulon, 2013] (Fig. 59). In dorsal view, the apical shaft is truncate and slightly sinuate in O. l. lacouri (Fig. 64) and truncate with a clear tooth in O. l. pupieri (Fig. 61); the other two subspecies show a rounded apex, sinuate to the left, being wider in O. l. kocheri [ Pupier, Coulon, 2013; Chavanon et al., 2016] and slender and more elongate in O. l. haroldi (Figs 62–63).

According to the map provided by Chavanon et al. [2016] the subspecies O. l. kocheri is found west of River Muluya whereas O. l. lacouri is found in the surroundings of Oujda and the Algerian border, to the west near Berkane, El Aioun and Guerfane; O. l. haroldi is found in-between the other two subspecies. Hybrids between these subspecies are found in many contact areas.