SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b2f234312c0a62bd1155db82cbb18c745cf99f116a9f6281756928063b208def' 
  AND token = 'NiONcQrQ50TSPHxwi05YlpqTDneYsf4FyMHqQOh5E6E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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