SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e67526951381400e82e2dffb320c4585000eb055c7af52180cbd34d52a3975a1' 
  AND token = '9tBDs89QW414Oq/ainPxR1Uu5fLt2bbWv8wt3wstKLs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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