SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '419a8a3fd6265b1d3cc7d1829037d10cf63570175506aaa4e82b67b62a41ea0e' 
  AND token = 'TxUSnHQObIbZrCwIxVpCpn8dsBJstkiZXhKVjJ+wISM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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