SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c96469c32a400c3b565225c75f334d2eadbb0ef70bf2328e2f44fce7a3481a4' 
  AND token = 'I0VQYLQqM1W2olqlKhBTufmDSz7WHcQd3TFrRABOXjE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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