SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7d2d996fd3d8218696abd14b51ceebcbb528f88331f70379ae9ef73133c87593' 
  AND token = '5JEy5rhtDu45Z8N8zuCGRW9H/DC+fYA68ILKwwtGFZs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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