SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9521f9d1ef9f7cc62651943e3b325f2172acb505de73951a7c940ca9774c2894' 
  AND token = '7OzKWmrjE6be1InpYaGVMIe4Nq+Y1OlPN3fJuDJvSqA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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