SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48ae05709f79c2d11a80d593cbb78de4a9494b5681118109a76d79d79888177d' 
  AND token = 'NDk0qSBMy9148Ttoz9AeRI32jMnJN+YO8WovIJgIUz8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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