SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '19839bd80f6cbb8e663ccfe6526fd41f4f7ad98c5fb9ec19852eb34477e321f1' 
  AND token = '0lG0I9mb6Y1qurlLKFZgDVmJKP/125oZVA1dxNh8IBs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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