SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac1d4ae6241b2d4652d0a802f1eed0ccc7f7c919edd51c4660e1ad132f499a87' 
  AND token = '5FBK9ZMQbs3k4dnL63+7kLguA1h3OW/8b/xT+AvQAxI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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