SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59e075c5891147f21a22c67c36d7e98848713439b4370802285d0faf3541416f' 
  AND token = 'GcsE65Ld/uoKefeG8ULsryYFa9B3hSjGi4V7/CCRpUw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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