SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7b680020942dbf4b527d51258f375c286022ec5301226249f60dcefcde7b0a43' 
  AND token = 'dg9IYRYZQBrQzb4ImQmDvXdBGLKG0l1knU5e9fp9wew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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