SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9ea81260413e4220490a5dd321efeba84ce5d2d91589e2dbc1c1ebe80e9d3dfc' 
  AND token = 'yhUYTnUp9mi+JQuAEFavmMJYW/3pgB76LKeaIedCX/U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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