SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6fc5d42467c13208c5cf8ea0ad1a9acb99884b26db314a5fe4a772bbe35da5a3' 
  AND token = 'TtrLCL3lufPlyWyBapTCSPcpCc3J9jv4HavBXQ4XeRs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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