SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '637870df26b141907ebe831cb0ea12a5f98d66f9996ede31dfa24b9ce8aada8a' 
  AND token = 'Soe135ntOw4+kFGM67KCp14j+u7eTftTZxsJ+w5eFbk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00062

JSON explain

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