SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9446c1cdd1b7c61f8d59da8cc6d33e64a0ac5f1a28c6440192f1dbb71f0014d5' 
  AND token = 'rFN9bmtTHrCFMew86skLdkFMnPBIxJrUR2TXiGffbbA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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