SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2ce63d0b584b616d0961a41e94198ea9c050906433dfb16bd27ba033bb8383a' 
  AND token = 'BqlA84rS88aUXk/IngAjqW/xm4ja4rqkfN2DKDDaWtk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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