SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7301b1410fed389266036bc6c2e43c221e5fccb4bc938cfe9c653a56a6f8f479' 
  AND token = 'K8m9y05u/7p5JHDazXbEr0wHbsaXP1cILYBnvgkdeHg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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