SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '464e5da9d6a6028a9a967d70fbf2f93ed1eb78110227acc79b3c4634ff0d35be' 
  AND token = 'U/Ca7jewoLzDqga99F2nLZKRBwN5pWX+2uQt8WQ12sc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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