SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '128682692ec092ab7e4f03ce444ae76fcf6e7f59e667b16a726bd3c6990dfe33' 
  AND token = 'aRZNxrvzOmj5QBDep9Cm9zMAzURQhFIJt9BvJhTzBtw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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