SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2c2593193e69b496ce2ef6e177ff4d0c89c9bc3537ac7cde08c02facbbb6e32e' 
  AND token = 'AQ1MhA7jfDDRmpfz9tdu6Fzyi8+/zqaNe7epaJNbXys=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}