SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b413cf4e24df4974e43a13230730be8d9ae3a23e74bd6be8b7045ff5e2ebb559' 
  AND token = '7vtGr2wy6MszcgdgUEycxLPq0nKEuK6KidRgaSfEy4M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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