SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9edd0050835b200d0fe2044763441ba9e9e049b512bf6cdc5e15dbebc5f7d73' 
  AND token = 'XRMosb1jG4kpjpqn3iNGGSlABnx5Bhql4OZyRafTh/A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00061

JSON explain

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