SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '036a6ce2f80f7ee3bb84147630eadae4fa92d7ab219e9204909da58d9db3a352' 
  AND token = 'KHWRCHDbKY0uACfO0kUYFuLo9NLeb4kNnhjnIDfaqG8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00089

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}