SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8f69580552faabf7e619bbb0cc67ae103c5a00ef36c9de89170bce92f5116e3c' 
  AND token = '1JtOwYqUQpZ8G5XWH8TjmLAj0+g6C3OmRO7/NrM4dBI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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