SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d64d5d4385ab825bd77bd57469aade98fce01ff81cca49040f00d6fb1f17d8b' 
  AND token = '37wEvU7e3XzP7gd4CgJVWt3rjrZzmMXmNi7vs0zB+Gg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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