SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '40dc11760fa288c0a4ac2b15974d06accba8ed873da8f6c51290540d5b8a131f' 
  AND token = 'NnbBc8F6Z8kC+mCY8gSAUUZLo3D7+CbneOlVHJSlyGA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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