SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee6208326d2d290809337c06953d1772e9c7fc059234d373594f7526e2e5c315' 
  AND token = 'WZw1Rq8AtaENZw0Lkpk3NDS7LX29VnQNyBZU02APJPo=' 
  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"
    }
  }
}