SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb6ce00b466eb9c252c01e6b73c70276fb6c883c09b20e4305a9e7ecd99db20c' 
  AND token = 'b2gGXW6Xy50N4iFssh3Gt4TFjXSwfzwnqm9+68asksw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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