SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '371569c6efaa41ffd2e06822839eda87fb75eb81b8c84105132297626273d4cb' 
  AND token = 'NvH5u/qGSQcYic9+gjFbbzOSJh8cI5K6vREOefvZa0k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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