SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '194f931481313087d99b2c5480a296cfa206e3f497878971d22f12f58b531ea4' 
  AND token = 'bZIEk9SZpGO1zXAgJBqTIC+WEftTsOqrmlIg+neMx8M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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