SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da2e04d9ce374034c77aaa81efb5cfa91ae1511cce5a5be6ff04357d53726bfd' 
  AND token = 'fxTbfnYbvJr2wG90reYc5FjTTIqtNn89iVGd7KLVy0A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}