SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bfdfa301ae6b76ea2747f6b5e89e06a51f9071498c55e3baf11f477dbd6bd608' 
  AND token = 'gEOyBQN2s7VTRgYRa0Fu/PfPJJLqZfhYcHrTzXlpwN0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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