SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6207058144e45bdac9b7c3a8cbf19de1a3a208017d2f4208774326102d5f3be5' 
  AND token = 'HophBl3wJ/gIBi0REqolYskFuccIu61vXtzKzNZE8eo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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