SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8ae636a502429a4c45e9f246ce8c575c2fb54ac40ebd92d12221fda70cbfaa54' 
  AND token = 'JLcBNDtKQC8CE4da+yhlXHuue02Y+XdjyGrpa3ZgeXM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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