SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1bcc6543068056123ac8481481c6f1b45be8b05a28460eff390b6c8a3f2a39b5' 
  AND token = 'pzgyzdSut2kTQsUxfQ5H+BHGZRatFDvb/opFGP/F9iw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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