SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9c18fdc18371d4ca1cff6326a80c9e6232de02c835565b35c63acb4f4308a291' 
  AND token = 'md3jTrmJuyTIgjRyPKB4F9xlwe5+nJDHQYVJPG0yzQg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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