SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ff39002d752e49eb81217c4b8672af48994b134ab0832c46b7b790a6ea6ee554' 
  AND token = '0Qth+ZqA58HmKS9Y/ai+erfoZraD3ZyBLeazl6H1Dcs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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