SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f82364c275dddf56a134473bea82f49ad0b21439638e0888b2e4959a52c6257' 
  AND token = 'kkoDkVIvJmjQyU8xB27JZ5Y9OLzAVI/E5C8+sJLs0dU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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