SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '154afe1c358f02ecfc7cf405c0269dfa9f89fb4ff7214ac47222bbd4b88dc0ae' 
  AND token = '04hZ4PVSw/aTm2j57vNx449jJisCQxicTCiElmFb3AM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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