SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bd01520d7370aa29ebfe03c3eec1ebdbd961354482c86a842d62528e96ef281b' 
  AND token = 'dhgfir0zjD+2ikaKTvpnBtd1PIQtgr93walzbXNFC10=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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