SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '60783e4b6c683876852b0ab791803397ed47ee5072058345ba963a3d31d0d692' 
  AND token = 'D7oZOFhpJRq17WIu0XS1FZJ40+xFL72Zcb+JQ3BnWRI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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