SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '478fd9325b11f9be8878511f0164714cd931e05d3438e61be0d479ac1311ace2' 
  AND token = 'KmDLDVfwkfkL+K2HPCukpIXby/U6uBf552wUKn6yhWw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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