SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f8fa72c6a23855d792759022330fdf890f4f346249ef6846478b712950b1bae5' 
  AND token = '8DUDoL6OcJK6qXjCmZHbZKT5YBJFYjxRkHeg98a2/7g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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