SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b64ac22658f41a240e661150f9bfe5eec93d82782c3f50ff51f9654e3ebbb4b' 
  AND token = 'l726WTArA6dgIKFjXBdctj+GuWQr941QZRz4O+mE+CQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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