SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '238b0c45f10c058229a0a15a9d5a82893d0ac56db2c7ec1955a763037529e7a2' 
  AND token = '1gE9bl/eozJNXIscw+iukqRZOm7V0JucslHUvpWaUKQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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