SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6ea57496705f39bbf132e66fb0ab1518c61b6edc0118bbab665940e1bb5b1bc1' 
  AND token = '3NhynLRwonimbKrycbrjsT0LDTxXc8yvVqEFx4CPS00=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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