SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2e38e00035591bcf47a7c2614198a797dae04e51bf43ae3c5085c7ae0f595c54' 
  AND token = 'cloSojDoOA8D4VswW0blR/nfcSCCLHfu93iymYaykjA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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