SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eaf762bb027bc2942d2672b005aebfb8c4d72c846e59e013ef7f95b6022dd03c' 
  AND token = 'SDBSFh9VycNmUlTOq+DKY/+BGY9H0m26ou8Y4xJXGbk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}