SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bfc13decc5cfa4307bb108011f4d1e20ed4dbe8d6b6991fe68e700dcf16dfeb7' 
  AND token = 'kwwvvNzFah6JmlZJrmzldGQAgJxDNSnKyoItJgjOuxg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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