SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '058b243bdb852aad8a59b97cbd3bd772ddb6a96039b062c991dec4d7fbd989e2' 
  AND token = '+pU2q35HyGlYZZaBjxtIxsfN9/3BxT/GICq0JKL70wQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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