SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4af946800fe3266f655ccaf0b87c74cd5a7ac7aae6494d8922147e1b5b5161bb' 
  AND token = 'MvUB9Ntm5tvrktjjsb0VlB8ooJVh7CvAwPqXzc0KYf4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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