SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '670f0644734dcf2605551395aa8b1e9e404cd5c9bf55fdb96633e64db0338057' 
  AND token = 'SPF7/4GxXHZLvzgfJ/YNwNreWG6FnFFifue9RQp0zRo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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