SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5c4d8a473747db312a36787aaf58a273916650e77f326e06208eb0115642e940' 
  AND token = 'HRcPSH8nyGT+biJoNOVXmI90vkhB91qCmi30icCh+xo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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