SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8d7fd0a411bc4d25f6e8623c0c3a2c26e0bb22b727244c4fb373b5f8c619efc0' 
  AND token = 'MTHTt/yqJ4XVzzGNspCVVuyCMffjBOCm96prtLm5rGA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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