The Southern H ii Region Discovery Survey (SHRDS) is a 900 hr Australia Telescope Compact Array 4–10 GHz radio continuum and radio recombination line (RRL) survey of Galactic H ii regions and infrared-identified H ii region candidates in the southern sky. For this data release, we reprocess all previously published SHRDS data and include an additional ∼450 hr of observations. The search for new H ii regions is now complete over the range 259 < ℓ < 346, ∣b∣ < 4 for H ii region candidates with predicted 6 GHz continuum peak brightnesses ≳30 mJy beam⁻¹. We detect radio continuum emission toward 730 targets altogether including previously known nebulae and H ii region candidates. By averaging ∼18 RRL transitions, we detect RRL emission toward 206 previously known H ii regions and 436 H ii region candidates. Including the northern sky surveys, over the last decade the H ii Region Discovery Surveys have more than doubled the number of known Galactic H ii regions. The census of H ii regions in the Wide-field Infrared Survey Explorer (WISE) Catalog of Galactic H ii Regions is now complete for nebulae with 9 GHz continuum flux densities ≳250 mJy. We compare the RRL properties of the newly discovered SHRDS nebulae with those of all previously known H ii regions. The median RRL FWHM line width of the entire WISE Catalog H ii region population is 23.9 km s⁻¹ and is consistent between Galactic quadrants. The observed Galactic longitude–velocity asymmetry in the population of H ii regions probably reflects underlying spiral structure in the Milky Way.

南部 H ii区域发现调查 (SHRDS) 是一项 900 小时澳大利亚望远镜紧凑阵列 4-10 GHz 无线电连续谱和无线电复合线 (RRL) 调查，对南部天空中的银河 H ii区域和红外识别的 H ii区域候选。对于本次数据发布，我们重新处理了之前发布的所有 SHRDS 数据，并额外包含了 450 小时的观测数据。对于具有预测的 6 GHz 连续谱峰值亮度 ≳30 mJy 光束^{-1 的}H ii候选区域，在 259 < ℓ < 346, ∣ b ∣ < 4范围内搜索新的 H ii区域现已完成. 我们总共检测到 730 个目标的无线电连续谱发射，包括先前已知的星云和 H ii区域候选对象。通过平均 18 个 RRL 转换，我们检测到 206 个先前已知的 H ii区域和 436 个 H ii候选区域的RRL 发射。包括北部天空调查在内，在过去十年中，H ii区域发现调查使已知的银河 H ii区域数量增加了一倍多。银河 H ii广域红外巡天探测器 (WISE) 目录中的 H ii区域普查对于 9 GHz 连续谱通量密度 ≳250 mJy 的星云，区域现在已经完成。我们将新发现的 SHRDS 星云的 RRL 特性与所有先前已知的 H ii区域的 RRL 特性进行比较。整个 WISE Catalog H ii区域人口的中值 RRL FWHM 线宽为 23.9 km s ^-1并且在银河象限之间是一致的。在 H ii区域中观测到的银河经度-速度不对称可能反映了银河系中的潜在螺旋结构。