SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd284887639f589ab937d5f5fb08f6c1ab9ab304cc23d08eb552d82412060c589' 
  AND token = 'j4tysqHcxIivRcY6NGrCC+PQCFOnT0cK4im94Kjum/o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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