SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0b79fa6fc3862aad3138dc238c40a2ffd717ba4599db46c6d8565f212635a633' 
  AND token = 'p0rqElwzRsvIfawilZwLnQ8iKQfL9wYIFuLIOxd2Qq8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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