SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ff3db8d52ee20f0b8bee9d7e4412ed2c996fc2dc5d7beadb89499f9665cb652' 
  AND token = 'EQShGLhB8IvAShr4UkM/XfUDoi2dAxpWd1kCcYL3p0Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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