SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f7a473381fd7926d3e4ce89727e3648a587320a592e9709db60c7eacfcb393f4' 
  AND token = '+SEh1FM/pQzlsIxgMElHuDd1J200ohBGIV5N5QP1bT4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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