SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '61f5cc36fb2144efab81df0b305524555cad8cd72f4e22bd545ca210bb897963' 
  AND token = 'B+f656VtOJXBzfPb6C2ToSukzlaDdfuC7vC6BAEOmoU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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