SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b11ea71fcc3f1e8f3d6b0a93269fa43b5c787821c4eb55ee0fe9575bee06692b' 
  AND token = '3zJ0DHuJChjUdJZvAIDOzNp04nW8OByjVbLMO2AgXsw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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