Biapertura ossiani herricki (Sinev, 2013) comb. nov.

Daday 1905: 171–172, Pl. 10, Fig. 25–24 ( Alona affinis); Sinev 2013: 330–335, Fig. 1–3 ( Alona).

Type locality. Sebago Lake, Cumberland county, Maine, USA .

Type material. Holotype (parthenogenetic female), allotype (adult male) and paratypes (over 30 females and 5 males) at National Museum of Natural History (Washington DC, USA), access numbers 1207845, 1207846, 1207847 respectively.

Diagnosis. Male postabdomen (Fig. 16L) with 1–3 composite marginal denticles near the postanal angle.

Differential diagnosis. Biapertura ossiani herricki comb. nov. differs from nominative subspecies in the presence of 1–3 marginal denticles on postanal angle of male postabdomen.

Distribution: Canada, USA, Paraguay (Sinev 2013), probably invasive populations are also found in South Korea (Kotov et al. 2018).