SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2528b39dbad1678f660073695bed525931b3959bca0608acae8f52b81a47f382' 
  AND token = '4Vg5oqllRV5I+Kwup3zGcXWM4hbchwe28YKn/yo41wk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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