SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '40eaf410d0d858602eba33459c6d0410a5b5a62863961f4dec7ab25b98a8f41e' 
  AND token = '3OHYb31xVqCCFVfx4KtrN2akswjJSgC/2kxDwg0cMJY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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