SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd2ac17e5107a7ea9b75a80bb70600cd8ddfff7dd9730c66318d989887771725f' 
  AND token = 'B0Crl1BN0PyAgIeX8kUHwWAbqFmkZH7wRHNeTJTE/7g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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