SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af50e788b73af1dce5fc0aaabc467dc251977103b6934ac0c2858cc9db7c8cec' 
  AND token = 'MnGCw9HlzM8nSG/fjbz1oB/LqDkfAzXRwRcwaHMvGyk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}