SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '18f9433efd7388975311073d4597c221e30aabb2cbdf3e4f54039690089bd087' 
  AND token = 'jDoG94gGjtJoaE+DomlM8zJsevWfucHaEymIznTPd9M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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