SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6e76acd0294733071409c26aac05b9da3f467e76bedd1d0969b960cb9bc5d1db' 
  AND token = '8GCpDi2Tm7JPe9o7cbb8uwXlwXrayT2S7MhlgJGCBe8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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