SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69f019abc48984630900b172b1febd974a8d0b1a8b492e2a142489f47cd409c9' 
  AND token = 'Z6Me3GogMICGlXIidtzJ2W9udruYBX2bPZuZUhikr+U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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