SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '66722512fe1cf398ea4d7547f06fc32963a12d5b4d623ed5603e941ad937a764' 
  AND token = '1V4CES9Lok+qri1wgSufopSSIvN5MblRv+4gukn+6zY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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