Motivation: Geographic occurrences are essential for biodiversity studies, but publicly available repositories like GBIF often contain errors and biases, especially for taxonomically complex groups like Carex L. (Cyperaceae). This work provides an expert‐curated global dataset of occurrences compiled from different sources to enhance data accuracy and usability. The final dataset includes 384,067 occurrences of 1790 Carex species. Main Types of Variables Contained: The dataset includes species occurrence records with geographic coordinates, taxonomic identifications, and curation flags (e.g., introduced, erroneous records). Spatial Location and Grain: The dataset covers a global scale, using the WGS84 projection. Spatial resolution is standardised to a minimum of three decimal degrees (~1 km, if possible). Time Period and Grain: Online records span from 1950 to 2020, but some manually georeferenced records are earlier (1850). There is also fieldwork data after 2020, specifically up to 2023. Major Taxa and Level of Measurement: Cyperaceae: Carex . Most records have species‐level identification, and some of them are identified at subspecies or variety levels. Software Format: Data are supplied as comma‐separated values files with UTF‐8 encoding.

Carex linanensis X.D.Qiu & X.F.Jin, a new species in sect. Mitratae of the sedge family (Cyperaceae) from north-western Zhejiang is described and illustrated. We performed a statistical comparison of the new species with other closely-related species from the same section. Carex linanensis is similar to Carex sachalinensis F.Schmidt, but differs in having leaf blades 1–2 mm wide (vs. 2.5–3.5 mm wide), utricles longer than pistillate glumes, with beak margin smooth (vs. barbate) and peduncles of lateral spikes enclosed in bract sheaths (vs. exserted from bract sheaths).

Carex duanensis Z.C.Lu, Y.F.Lu & X.F.Jin, a new species in limestone areas of Guangxi, China, was discovered and described. The morphology showed that C. duanensis is similar to C. calcicola, but differs in having culms central, leaf blades 3–5.5 mm wide, bracts longer than spikes, utricles 4–5 mm long, shorter, and nutlets abruptly contracted into an erect beak at apex. SEM microphotographs of utricles and nutlets are provided for the new and related species, C. calcicola.

Discovery rates of new plant species need to be accelerated because many species will be extinct before they are formally described. Current studies have focused on where new species may occur and their characteristics. However, who will actually discover and describe these new species has received limited attention. Here, we used 31 576 vascular plant species distributed and described in China as a case study to explore the temporal patterns of the nationalities of the taxonomists. We found that most recently described species are endemic species, and there has been an increasing proportion of species descriptions by resident Chinese taxonomists over time. The proportion of species described by resident taxonomists reached an average of 80.8% between 1977 and 2018. By contrast, species discoveries by non-resident experts, often non-endemic species, showed signs of levelling off. Our study underscores an urgent need for training of, support for and collaboration with resident taxonomists in megadiverse countries with a high potential of discovering undescribed plant species.

Carex sect. Mitratae s.l. was established by Kükenthal in 1909 and can be distinguished from the closely related sections in having nutlets frequently discoid-annulate at the apex and a persistent style base. Based on field surveys and specimen examination, three new species of sect. Mitratae are described and illustrated here. Carex fatsuaniana was collected from Yunnan and differs from C. truncatigluma in having the utricles nearly glabrous, the nutlets with a ca. 0.5 mm long beak at the apex, the staminate spikes cylindrical, 5–7.5 cm long, 4–5 mm wide, and the pistillate glumes acuminate at the apex. Carex damingshanica was collected from Guangxi and differs from C. breviscapa and C. rhynchachaenium in having 3 or 4 spikes, the lateral spikes cylindrical, the pistillate glumes, utricles and nutlets all shorter than in the other two species. Carex radicalispicula was collected from Sichuan and differs from C. truncatirostris in having the staminate spikes clavate, 1.5–2 mm wide, the pistillate glumes pale yellow-white, 3–3.2 mm long, acuminate or short-awned at the apex, and the nutlets with 3 angles shallowly constricted at the middle.