SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd698288b37f7bb298b07983482e0b1bb5a3b6a0091fe85166a9566829f99649' 
  AND token = 'Zq+GjDZCB8H+DVMKkLKuGHSdWSpevJ0wd0KnICh8WLg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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