SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b1593db3778c9b3bd729b42e420ac35a87c18907bf60e7107bb172fb829eb631' 
  AND token = 'H+HfEfBdRIGFVQ10eHonxtg3YH3QRX+2W3DvoHbCFaI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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