SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1c173419063493649d530261a4d6fdaf73949a21d8f027d0d119a527c4703cc9' 
  AND token = '6EQLWCMCcS93/J9IsVW56uSmTVuK04KDP/KnV4i1zTE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}