SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa0963b316336d5b457f6aac96991940a5121896b1c344dc24cfce999611a2f5' 
  AND token = 'AYkiqKqoqxGzTCchoduQCh4ielznsYABG3TI2q72rko=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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