SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b955fff9c5930e4a0ee9e9d42a271c9d9cbc6363696709ab5e65ffd2155d1f7f' 
  AND token = '4nWDFqA5aZnqhYwf8myy+xccpGvxKkJqejbu/3pfZ+o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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