SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8f139f6588a23c2650922355870058f362907d4c46804540d8e861b5f7311c12' 
  AND token = 'RffBGtAThB9dNTqtozcyB8M7o0VDgvXZY7O/zV12z1U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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