SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd26d1cda46c5cf8ad0e11d4b40e610a6fbe6b1354323f3d8c0f191955e773a57' 
  AND token = '88WapwWi8hSqadI/YaD2kZMHD4XfwjvJtN7OguI+BZo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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