SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0be0ba461d081c55f8560d21cc8dbb629e37bb0c50f3d4ab7851f369f0b9f0d2' 
  AND token = '7TylF0U71E+fvw6tyGBnyGW8QDNcI6GbuuCHbmYV41A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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