SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '08b99b577ff1984bd56b9cfe607118df159a4b0a9d99a8a2cabc96cb00a8c455' 
  AND token = 'TE/1myLzjszbyZx57orH19mExUefqKgkCORP8ClxPio=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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