SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '50f688546099707d1d0438e46fb8067d0c9f3df71a7c0aa208deb7654e8cf657' 
  AND token = 'uvPdWfO3xXPJO0sNQA36aEq/wyyhV+/sRqnUAbzeKYc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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