SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e23304b5dbcc3a73c2786c76b494572703ba4ecea0eca3bc7188e797cff7c5f9' 
  AND token = 'qzgg/yny1nAXMrPw1B6goD/uW4pq4S0sfCL0ceSnkn8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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