SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '49226b2143fed8c88e4bf6163490874f55b6f8f1a3aeeb8d9afe0be57a06f92f' 
  AND token = 'VznimdPQEbmvrafE+dTmjG4uO5InH7/0cj+NCOoPcgQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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