SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80168077dacea0e5d74d00e96df390b0f565687233e44c76b57019fea4cb11ee' 
  AND token = 'mXxWIXsR8baqDhgZQT+NP+acOPFUWCwKYBBfcz5uFLc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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