SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ebf2d095cce685b8b5eaa069b2fde3651d18adeb057b9f3e1425403d8845c705' 
  AND token = 'g025cA0J22Fnk/cNvbYJzr40389cbD6GdeGqz6P6yQo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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