SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6957b9f4e46bd25a03a69570a916d9b20cf672208b11493d1b098d9a1edc741d' 
  AND token = '+9bMG0SmO4oGdD9WNKfKrtIz78KGOC9d6NiLCVeLIbY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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