SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b0810d4357651f3929ad647948643d9a6d08f5a102c8c0249f33269de70fbc4a' 
  AND token = 'Xt0mPfrlUdCMR2QuPtQBwK+05eotr6pJqKaD0pr6SRo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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