SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '80217e9f994f71a83dee3a9739c26fcc9f3ad069e6544ca82f23311d14a36bf0' 
  AND token = 'dshIlRT+N+SaInweX6rsq+RYETqF7CRME2K3Cp5HP8U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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