SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4856130bc06c3516288116fbe03bdc7ea8f1761cda1c4395eb9fd47096e124dc' 
  AND token = 'UQSly1b9PvzxMH7BqiJxCIglbZjhyuO1YIuD6ZW4mD8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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