SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6cc0502e679e891d1957831d9ef177b44e6bfcfb95ad8488b48bc466a8360aef' 
  AND token = 'pFMKKNw2ZqySVuSm8syyzC1CaNHiKiFIgDnn1gdJk6I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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