SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65a107c5a123f6de60b87df64e520550881bf08b25c1cdc46e028b10ddf9d75f' 
  AND token = 'XtrYZhzcWMxdgDdvvyWGqM3kxqaOmoaeU8ZtrDodAw4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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