SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '860a844d7fac7f620ee5bc2162c0eb50f751da9d8a2a4781152b803a6bb9659f' 
  AND token = 'UU34lggdFcfh13/58fER6/wVQkseVAFsT3ynOpEBmK0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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