SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0e8b82ea6ec699b5f2af27cf127939358c7e4a446c78cd6a4f05e17953a62bea' 
  AND token = 'AsjmjUzUOy1PrjQUiyKboUh5lSD2hejj18VH2XMoeoo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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