The bigeye notothen, Trematomus tokarevi, is a rare nototheniid fish with a putative circum-Antarctic distribution. Due to its prevalent deep water occurrence, this species is rarely caught and its biology poorly known. In addition, this species has been often misidentified with Trematomus nicolai, a morphologically similar species with a partially overlapping distribution. The odd catch of a few specimens of T. tokarevi in the southern Weddell Sea enabled us to provide for the first time preliminary data on reproductive traits and individual age of this species. Fish sample consisted of five females, collected in the austral summer north east of the Filchner Trough at about 750 m depth. Based on histological analyses of gonads, smaller females were in early developing phase, whilst larger ones were regressing, suggesting a summer spawning season, as reported elsewhere. The analysis of growth rings pattern of sagittal otoliths allowed to estimate the individual age, which ranged between 4 and 10 years. In conclusion, this species exhibits most of the common biological traits described in other trematomids, although with some peculiarities, showing at the same time low fecundity and small egg size at spawning.

bigeye notothen, Trematomus tokarevi，是一种罕见的 nototheniid 鱼，推测分布在南极周围。由于其普遍存在于深水中，该物种很少被捕获，其生物学知识也鲜为人知。此外，该物种经常被误认为是Trematomus nicolai，这是一种形态相似且分布部分重叠的物种。一些T. tokarevi标本的奇怪捕获在威德尔海南部，我们首次提供了有关该物种生殖特征和个体年龄的初步数据。鱼类样本由 5 条雌性组成，收集于 Filchner 海槽东北部约 750 m 深度的南方夏季。根据性腺的组织学分析，较小的雌性处于早期发育阶段，而较大的雌性正在退化，这表明夏季产卵季节，如其他地方报道的那样。矢状耳石的年轮模式分析允许估计个体年龄，范围在 4 到 10 岁之间。总之，该物种表现出大多数其他吸虫所描述的常见生物学特征，尽管有一些特殊性，同时表现出低繁殖力和产卵时的小卵。