SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c1bfcdff2f6cc0031b8673d1629fc22ab4e36dd3572939ee93fcafc4259ec9e5' 
  AND token = '1Co+r11wfObRzzSegOHdcl92paKsdJD48QaEOerQkSQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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