SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '83b51a705a2576c0c0b5664439d9c77ce0235fd1a6ac58688ab3ffa0acaa15f6' 
  AND token = 'Hq7Z1UeTVTCMtPzPi7CKFcouIUKXHIq5Z1PapFAJauM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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