SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a9fa35fa0b0fa2b9642d856f277ea2554f32a86f22337f95b032412786ce5721' 
  AND token = '5Cg8NbjbMYTLyA37Su06KY/ATsgWbVY+bxaFrYnYO8c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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