SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccd977afd35369537b8348419b7d9505e831d9c552368c53189ea48ac23645c6' 
  AND token = 'enrnlWqJ6Ck8dyCn154DuT6aVNbAOqNJn2PsxySdNoQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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