SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9530953f0e86a91543d5b704c2537d2bef1632e588927e9c982b885ff6155f4d' 
  AND token = 'oWSvNyrxWibxPC4LimGo3saVzpVdKEPChaM4B+zigEw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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