SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bc398e9f5828b8fd4c7a88365d329250f9b72021df7172f8f69858e1666604f0' 
  AND token = '480TEepSm9+QxyrhOxGnhlC/RGlgB7HiKbnqK2PU+rA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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