SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5294e0a2beeb27d8f135c4b53ddab42fc835b43a83fd9abe171469714843ea17' 
  AND token = 'OwDqMD6Dax0CZoGqjjoHKCFaNiYE7h+SzVnk0sdmHgc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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