SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c11227c3d21ce2070b8b88a42e491f46cf5892c9a54ea6297817f210135537b4' 
  AND token = 'CeQ3XDkOdwcZROjQOYNDLxXYnLJssMnuyBSFggCsdb0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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