SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3b5d518b932e2daa817636daa0fd32fbff55bdd25ca4b0667d7e22e0f5317b40' 
  AND token = 'zZwqmHnVpvWNhPaR4CzS51FaL5/ACWLhV9lp53dx+K8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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