SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'be7e6bc489a3eeaefa2466d5dd7915f9dffd745372809d78a83f1ea751017f5d' 
  AND token = 'wEkUjALn7GDl5PDct5v7tdakWMnEeGv6tGtSzCif3jw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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