SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2dcc61cd4b9db85bd83fec6ea3d6321d86c95c1ab4388d92c65836802a01ff9e' 
  AND token = 'sqZeAyRYdUEf7eppcbBgICfduY/0zHmxz9VeMsnFrq4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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