SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '48a6a1e225123e671b9c4e60b0afc8bfe09c0ce29c2f76f6802f3c22be4db96a' 
  AND token = 'yS2oXzar82nJryE9Ni7rLX7Oke6SEmCbi0lJPk6NgVM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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