SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '82a54d54d49b4ef10d25d8b5196b70a5ec9a6e29fe5f47df14e92b4b417674eb' 
  AND token = '7GakOsHoDneddR9KxVypSrmWmb2aLNN0PsIjDRD1PiA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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