Hydraena (Hydraena) numidica Sainte-Claire Deville, 1905

Lamine, Smail, Lounaci, Abdelkader & Bennas, Nard, 2019, Biodiversity and chorology of aquatic beetles (Coleoptera: Elmidae and Hydraenidae) in Kabylia (central-north Algeria). New records and updates, Zootaxa 4700 (1), pp. 102-116 : 106-107

Hydraena (Hydraena) numidica Sainte-Claire Deville, 1905

Chorotype. Endemic Maghrebian ( Algeria and Tunisia).

Material examined. IG1 : 18-V-2013 (168 exs.) , IG2 : 18-V-2013 (122 exs.) , SA1 : 12-VI-2013 (6 exs.) , SA2 : 12-VI-2013 (15 exs.) , SA3 : 12-VI-2013 (3 exs.) , TR: 6-V-2014 (5 exs.), AA: 18-V-2014 (3 exs.), KH: 9-V-2013 (9 exs.), BH: 14-VI-2013 (18 exs.), S1: 29-IV-2015 (6 exs.), D1: 23-IV-2014 (3 exs.), A1: 7-V-2013 (3 exs.), A2: 7-V-2013 (35 exs.), A4: 7-V-2013 (3 exs.), A5: 7-V-2013 (4 exs.), A6: 7-V-2013 (4 exs.), O1: 9-V-2013 (3 exs.); 24-IV-2014 (12 exs.) ; 16-VI-2014 (28 exs.); 29-V-2015 (32 exs.), O2: 9-V-2013 (12 exs.); 24-IV-2014 (17 exs.) ; 16-VI-2014 (15 exs.); 26-V-2015 (4 exs.), O3: 24-IV-2014 (3 exs.); 16-VI-2014 (12 exs.) ; 26-V-2015 (8 exs.), O4: 24-IV-2014 (15 exs.), O5: 9-V-2013 (18 exs.); 24-IV-2014 (4 exs.) , BO2: 18-V-2014 (4 exs.), TG2: 26-VI-2014 (21 exs.).

The species was recorded in Kabylia (the Djurdjura massif), the Atlas of the Blida (the Mouzaïa massif) and in Annaba (the eastern part of the country) ( Ferro 1985; Kaddouri 1986; Aït Mouloud 1988; Lounaci 1987, 2005; Berthélemy et al. 1991; Lounaci-Daoudi 1996). In the study area, H. numidica inhabits springs, headwater streams and middle courses of rivers with rapid and moderate flow at altitudes ranging between 160-1200 m.

It is an abundant species throughout the investigated area, collected in 92% of the sampling sites. Despite its abundance, H. numidica is a threatened species in Algeria because of the habitat loss due to strong human pressure. Among 23 sampling sites in which the species occurred, 16 were subject to different types of adverse impact such as domestic water pollution, grazing, and extraction of water, sand and gravel.

However, in Tunisia H. numidica is considered as a species under threat because of its very restricted distribution ( Touaylia et al. 2009; Bennas et al. 2018), in only a few localities in the north-west of the country, as well as because of its low abundance ( Touaylia et al. 2009).