# Genetically confirmed first records of an egg and a juvenile roundscale spearfish, Tetrapturus georgii

## TL;DR

Scientists found and confirmed the first egg and juvenile of the rare roundscale spearfish, helping understand its early life and biology.

## Contribution

First genetically confirmed records of an egg and juvenile roundscale spearfish, Tetrapturus georgii.

## Key findings

- Documented first genetically confirmed egg of Tetrapturus georgii in the Sargasso Sea.
- Reported first juvenile T. georgii with morphological and site data from the Subtropical Convergence Zone.
- Provided insights into the early life stages and reproductive biology of this poorly studied species.

## Abstract

The roundscale spearfish (Tetrapturus georgii) is a poorly studied species with limited information available on its biology, ecology, and population status. Although the adult life stage of the species is morphologically distinguishable from closely related species such as the overexploited white marlin (Kajikia albida), misidentification is common, adding to the uncertainties connected with population assessments of these pelagic highly migratory species. Although genetic studies have recently confirmed its distinction from congeneric species, much of the reproductive biology and population dynamics of T. georgii remain unknown, underscoring the need for further research to guide conservation and management strategies. This study reports the first documented records of an egg and a juvenile T. georgii. Here, we provide photographs, morphological descriptions, and collection site data for genetically confirmed egg and juvenile specimens obtained during two multipurpose research surveys in the Sargasso Sea Subtropical Convergence Zone. These findings contribute new insights into the reproductive biology, early life stages, and ecology of this elusive species.