SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2aec38697b1c9b2bcf7b22ab065c56766f119ca67903fb7caf14b55a81effedd' 
  AND token = '4dAB7OdtHFpvk9PxFGWRxFuWUiPyA1FfeGGCeZgrc1k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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