SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd95fd0192d16797dc751cbe1d1be71ffff36a30a5bb6d820de3742900a209f4c' 
  AND token = 'vbzWk9iztOYEhmb4rlK9iyg+7M+9loFtZ17ZnCEqIsI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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