SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a43d55ca42a4e76ab0649066e4e0156be5d27d9730879010a38ab96108a3e298' 
  AND token = 'HNKKvD7LQnUv0EoaPvXjaQcfC5SymApHGHtJH2nEWMk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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