SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '72e1361490db6c0dce96bf27a5886799401fe99201fa3adea8e0661bfedadbf1' 
  AND token = 'Tbbjj3eW9FiUKP0c/H5Tqn9AQPMAVtmxQ5QIaebS1zw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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