SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09305ae14c03e2876e0c85cb572fb179177d42ce2bdce38bfcadb72b4c219892' 
  AND token = 'rz/YVn6B/eWK6gOrAWYD58ZwF6uZKGEaLHOOASsiRE0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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