SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '87e8444801fd153ca21bba896b6e4dc128efd598bfac54dc273276ebacca07a8' 
  AND token = 'LiHRxhuXefTTC5cl1HubqGgdGtowLxPkOhZRFGVwR/s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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