SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1acc96524489b2f4ea38c2fd91121a2571c1acc5e26cb384ab91d4e191d39bd8' 
  AND token = '+34Nshq3k3FWiBpxZAwyDBvgfmPsJaapzXjo2j8YfBU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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