SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd088fb043b1017e446c16a8759f87385b534a2b9110bcf7a13e2db8c478d6ec2' 
  AND token = 'AKxHmZaZZaGQfhxqvWGIGAV7KnA8/CKSDCEE+vDg+B0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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