SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cadbd9ede979150cae0f0d9607d1e44361a7403af21c381142d36af7e65ba867' 
  AND token = 'lDhGFaY9prKqlKG5nw7aghN+obAXvp+hWfeI2YGFo/g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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