SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5825cbc383265cc0471f345751ca5d9cde35604afeaaa072648711aa62699f46' 
  AND token = 'FpzUm4P36oKO1RJE7HWGyShuQ2J59QkcxHZQKAnnSTs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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