SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3c616ff2180cd7e10f313f3510227a237a60ac796954d0b6be923bf4bc6c8556' 
  AND token = 'kfF4LUPLQGD9aT2WLnIwx4/yTyBdGPn14YQJLHYyxj0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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