SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9abfd1b9308e7653b712724b1ccf9dde537f30b1e97e8d9358e5fa4308a224a4' 
  AND token = 'rEB1ksGIYTrTQBjVN/Q84eT6LjJH2fz6GjjwPnqK9s4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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