SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2e08a1bfc17787fe650dacd60341d4b296ed10b39cdf0100177d6880124fafdf' 
  AND token = 'eYgaDAJxhckerNJ44KxdBZvM7n8au/oKvIf7kjDT314=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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