SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd683f31425dd5eedba20f523375d19e1b52a0eb95b4f0148e76753a1a84cdc79' 
  AND token = 'eyi8lzOX40HIp0PCQ+VHagO1HKhXZcSmHKmCjwjckyQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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