SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '64b32211d80fb5dfebaf2b5c3bac67561d495134de2d513a8dabb68860cdced4' 
  AND token = 'NkGmWpjECiyW909DsLagXjnuArO6fBxRXYuhNdvh294=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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