SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b3ca994cb9017abf45f96ac8b2f07a064c3f886c65c742763b6cfb8dd4f837e3' 
  AND token = 'XWwmC/fFtvt7BKturnYGoudTUx2KlBch3NGRsj+rH64=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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