SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8880989d31e4665836f5af5f55d317ebe2db3f7ae603ac015b402eebf838557b' 
  AND token = 'upJgubqpofBahmlGEH5GL8k2uXnORTpYLcbAYujq8kw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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