SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cbd46f9aa05eea31738f6198f6b620e4c85312871adb16bbfcbe232a903a46b3' 
  AND token = 'H+KwKLH+XcnsK8yhWRnGcESrSRtHIcQrFw98HjsmDx8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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