SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '076d3d279fa20ac305afe440dfb70c5affaf37d70f9978920e19deca0cd73f61' 
  AND token = 'y01XZwxNE0rsB7NOqM14ZWCVLSZujiLIwasZ8waxtVM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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