SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f23b715d996305187402d08cd209ddbb21c483451d37e89e9c92c5dad2162f71' 
  AND token = '/vwnHFosoN/iskZfuXDQMhr+6W6wMxrO/LCHFJNx+Xc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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