SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a9388f2429c0833fd0e9621be1ed1e311c4e860f75b46eb6f4b7c9949182fe46' 
  AND token = 'ixl+9nBM3HK8vRPhnBYlG0FhW1UcEBCyD+GfwJsbv5U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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