SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4f7bc1c8037ff2a84c3fa245749eadd39eaa116ebe6851105b1cb1df67244a09' 
  AND token = 'BYy5Vm55VdUF+IjqtCRFH2t7DVedP2kwmyyByFDFNfA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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