Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be233238ef3d6eb5aae56a36ca75c00c76e1ee341ff64bab9dce4fa95955dbe4' 
  AND token = 'ssz3WNu2tGpj5uIqHiHnubkMbGOWp+SVfgg8k/Ipcg0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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