SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '91d585ce102c1a0566adc0fb41b3e8c32ff132beb947dd114d86b57f7fffc681' 
  AND token = 'ReiephjxgKVIOk1RwSSKjC2UsNjHPVYRHYqDBRxLFco=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00117

JSON explain

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