SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '48ef30aa4dc3c944b53152258c1762930df1eab3c66357599e208dcdf96626d0' 
  AND token = 'VEywSvcNTxVs1ezpuNwKijefguNrxqQyoYKlUcY88fw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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