SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3192f86b932dd8d92f1e38e11ecfe5ce096b35d83f7df0f998de734be33308e0' 
  AND token = 'T9XDiWx5wnLoXKpz0LvWwJH40XsfSVbwoipa6iDiEhk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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