SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9bb35356c80bfd63c76d2eafcb236e9066b83d0c31e1f9c2bd7dfcc9db74912a' 
  AND token = 'HudLmjTBjvOCn+qHR7JWTpMw3K9Sw6uLiTkxQEkKwVg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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