SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d6251a103c36eba7da5ca17bdfdd72f375b492473ec223037b28b94b31d23eb' 
  AND token = 'Mcdoa6zJpWC3cBZLgL2nawsgOuSaNQNsnjViEAW0Agw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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