SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b6b1fea1d175dee37018088e6032500f70e4f6145c92a5028987f61f30fbf701' 
  AND token = 'ZOQm4WsLrz6/GTxuOUmrqel3chTVAkxQNmhxbk0Bq1g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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