SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f6f47c370cd0f9c5d9928882cacc483b1dd545519f926c7960e2ef9811cd9e26' 
  AND token = 'WtGGEd0LMkOqlp4QZd7xA57IYlfgj3//Ozxst6TQAuw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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