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Species · accepted · checked 2026-08-05

Argyropelecus affinis

Slender hatchetfish

WoRMS 127307ITIS 162216GBIF 2347596key worms:127307
i

2026-08-05: itis_id 162216 via WoRMS external link

Silhouette · João Pedro Fernandes Moutinho · CC0 1.0 · PhyloPic, drawn from Argyropelecus olfersii
Slender hatchetfish8.4 cm
US quarter2.4 cm

max · worms_attribute

Argyropelecus affinis Brauer (Valdivia) Subject: Sternoptychidae Tag: Fish
Photo · Jules Richard · Public domain · commons

Argyropelecus affinis is a species of ray-finned fish in the family Sternoptychidae, described by Garman in 1899, found in the tropical and subtropical Atlantic, Indian and Pacific Oceans. Common names for this fish include Pacific hatchetfish, deepsea hatchetfish and slender hatchetfish.W CalCOFI holds 1,033 observations of it in 2 datasets between 1959 and 2023, as larva.R

1,033
observations
1,033
records
1,033
sampling events
1959–2023
years
2
datasets
larva
life stages

Observed in
i

One row per dataset, one cell per year, darker with more observations — the same strip the front door draws per dataset. Each row ends with the name that dataset uses (dataset_taxon); the accepted name is written once, in the title above. A quiet pill marks a name the authority does not accept.

  • Ichthyoplankton 1,014 obs · 1,014 events · 1959–2023 · larva
    name used: Argyropelecus affinis Slender hatchetfish · code 103
  • Mesopelagic Fish 19 obs · 19 events · 2010–2012
    name used: Argyropelecus affinis · code Argyropelecus affinis

How big is it
i

Every mark is a measured length with its own source — hover one to read it. The reference objects are _data/size_reference.csv: two of them, the 505 µm bongo mesh and the net's ring, are CalCOFI's own sampling gear.

Ways in
i

Read from taxa.json of release v2026.09.11, written at release by calcofi4db::build_taxa_catalog(). The catalog's index is /species/.

Explorerdb-query
ERDDAPCalCOFI's own server, the Ichthyoplankton table constrained to this taxon
https://erddap.calcofi.io/erddap/tabledap/swfsc_ichthyo.html?&taxon_key=%22worms:127307%22