SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9df4066af387a4da70d83c5dbffa383cebbbf84e7e8bd9972dbb9ebed30a9d83' 
  AND token = 'TUHgODPsZct1X+gJw0ajjYyjWfpNJVEhBPzeoeFNNt0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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