SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '98bf7b72d379f023d936c39454bd6775c08f3297fbde7c62722acf8d8fb47193' 
  AND token = 'SFcYOW6kLd/Wgu6W6qR1i86vulLzaiwoEvQFxlaWeuY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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