SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6e3b991b0fa6a2efb7eb4c7e2428f649a7573cd2d11ae18fc65853c48b85864b' 
  AND token = 'haEm9kMPO/y/8uUrdhpQVg5jY2j7lfCjxT7XGy6Dznc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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