SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '033f9594cb404972db7a34ce92f0798c456bc9c04caf129738f27cd6a09b86a3' 
  AND token = 'kjdANwwNCZ+VQGU7Y+FLkfuO5LT8FzLKVOn0zIrZpdw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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