SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '222020edcea7397eba0a1b9698db2959e020542dfaedaee130ddf1678760a1c2' 
  AND token = '31iKWRYyxkT4cy823cCiXvf/NZml3lxthuPxX/20EVc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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