SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '707f7416e99596dbf13757f1d6b5124ee4d19ae2d9e5cfcb0830c7aac42ebd9d' 
  AND token = 'ebsUvhacsHZx+fRZxxnadbPDC6sAsVI/xW1T67wk2tg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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