SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7ab129735546a1df0f42e04b16083285379d4035ee16963068e78b55b24ff444' 
  AND token = 'FamKIjnZrjsqG21rULP+xRNda99rQXMZhZY3yggAklM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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