SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd4f1819fc981d99b0742b93869c735a91b36e7d55dc5c347ac61cd44edf6c67' 
  AND token = 'K5x4fVrYdsC8o2qM4fqz/z3hI8JfV8PI4qIxjUDXB1Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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