Figure 9 in Fregetta lineata (Peale, 1848) is a valid extant species endemic to New Caledonia

Figure 9. Comparison of underparts and underwing patterns of New Caledonian Storm Petrel Fregetta lineata (n = 30), off Nouméa, New Caledonia, January 2020 (top row) and New Zealand Storm Petrel F. maoriana (n = 43), Hauraki Gulf, North Island, New Zealand, November 2018 (bottom row). Variation is scored into four main types for each species, from the heaviest marked (score 1) to lightest marked (score 4). Underparts streaking Both species can show similar coverage of streaking on the white belly and a tendency for denser and / or thicker streaks on the flanks. Score 1 for F. lineata (23.3% of birds) is uniquely patterned, with continuous and dense rows of oval dapples, rather than straighter lines of F. maoriana. Score 2 for F. lineata (36.7%) is the most common and similar to the coverage and shape of streaking as the similarly common score 2 for F. maoriana (34.9%). Streaking on F. lineata tends to be denser and bolder giving the impression it is wider. The unstreaked belly area tends to be cleaner white in F. maoriana. Border of dark breast The border in F. lineata is positioned higher than in F. maoriana, towards the centre of the upper breast, creating a rounder and less straight border than F. maoriana. Underwing pattern In F. lineata, the dark leading edge to the inner wing involves lesser secondary-coverts. The longest of these have partially dark bases creating a characteristic ragged border, with strongly marked bases in 83.3%, limited dark bases in the remaining 16.7%. By contrast, the dark leading edge in F. maoriana invariably shows a clear-cut border on the coverts, only occasionally with a few dark spots in the longest lesser coverts, and never forming a continuous ragged border as in F. lineata. Usually, some greater secondary-coverts and most / all greater primary-coverts in F. lineata have broad dark centres. Thus, the white underwing panel of F. lineata is noticeably less extensive than in F. maoriana (Hadoram Shirihai, © Tubenoses Project)