SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4af8a052f7c868dc170c0ea6d62a580af040ee498738e3a95a6d2bf65ece32b3' 
  AND token = 'JAO9nZBcjes3tDK+OIrJ8aH8NWbbnAMMd8JDfOmA/u0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00081

JSON explain

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