SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1c72a9155be8fec26a48bd519f03e58a853e6303102251c35410ce51f341662' 
  AND token = '3ENrYfde+W3328fWruJ1klN06HuQ9YOwUUaHDbr4pC4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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