SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b96cfa16ccf93b84dd15b427e7441890c4f02ad8b87f2b22d2b91038ed96561d' 
  AND token = 'If9DpmR00KFhTC5tcCKLXe9Wbsr3jml/FuKqYtNwxMw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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