SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '368d67b67fad809cbcec6347ab08461905a00f625037a90454c71eb8a583d4ce' 
  AND token = 'eyj6f9ILrUpYJKZPPgyaDSp3aR7VJsuW1TooWIcJmNE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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