SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fb39cc92f980e87e14c3ccffa3ec6a54c5f50d7b136017d91abb05b60a300235' 
  AND token = 'YMoKnkizNmVFrPyI5TNhZxxsSwkk1yXgc3kOpyu30nI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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