SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5603c274f2888b117455a7e71feac9de63e307da03e31c0ceddadc18dfd3ac23' 
  AND token = 'KbZBEifeeF8y/7pu4VoWzzZM9g6LD+W42raeeg8N0g0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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