SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58b3dd1105fcc9163886a78ebbaed73e1b588f97abd03217c8e20b9de84af66b' 
  AND token = '0G92vfsppEykaQhGG3LefldfYIiUcnxqg3NgOTgeo78=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}