SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '41b14b4c2ae849ec44634cb2079b361a05eb35c464d05babde5edd2210d53d78' 
  AND token = 'l7hGZsJj/LKGvg1LfsFhNDZrsdSqvp6pQCOcxPpvIMU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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