SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5947c6f3331a6b81d1db60772d45bddc0d686446c2e8ae96354d30e87691ab2e' 
  AND token = 'VOmX0K6NZEhblFqHYhBqrmpvuf2xViOB7YcAUzlfUFw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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