SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'daaec82699f61a6e4b2c7e6a0439f110bd33c21021f9a8b6f4f535630c04f3e7' 
  AND token = '9XB8IjDlvUIhwMjpwgG/DfCpmr5N3lCpH+F7TcEM8Mw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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