SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '22db110cc794f18f82cab4e4d76a64099d57d2402cac1f7c8951571ecc4f3d0c' 
  AND token = '4eRGzqr903NG2auXcWG5WPcg1fTpZ7QuQVqtIicEkho=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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