SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ee2541d1267a0597e76de553020c0c1637a89402b555d4a7c2f7e8bd07bf6539' 
  AND token = 'EIYEBcAq+BzQbIw4Cp/qmd7smQrv2tyeV09NRlZHvnY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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