“…Repeated glaciation impacted on the distribution of many New Zealand taxa (Wallis, Judge, Bland, Waters, & Berra, 2001; Wallis & Trewick, 2009), particularly in the central ‘waist’ of South Island (Trewick & Wallis, 2001; Wallis & Trewick, 2001), a region of low diversity known as the biotic gap (Figure 1b). Originally named the ‘beech gap’ (Cockayne, 1928), characterized by the absence of Nothofagus (southern beech; now Fuscospora ; Heenan & Smissen, 2013) forest species (Burrows, 1965; Leathwick, 1998; Wardle, 1963), a loss of diversity has been recorded in many temperate and alpine species (McGlone, Duncan, & Heenan, 2001), including 2,322 invertebrates (Taylor‐Smith, Morgan‐Richards, & Trewick, 2020) and most likely reflects repeated cycles of glaciation (Hall & McGlone, 2006; Wallis et al., 2016). In species with a broad sub‐alpine/alpine interglacial distribution (Figure 1a), areas to the north (north‐west Nelson) and south (Otago/Southland) of glaciated areas are regions of higher diversity that probably acted as glacial refugia (Figure 1b) (Dussex et al., 2014; Leschen et al., 2008; McCulloch et al., 2010; Neiman & Lively, 2004; Weston & Robertson, 2015).…”