SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f00deca50239927016671a0ffe5176f3dc8d81707a6026c74d995a5431bb9405' 
  AND token = 'rHhSeq5utyalDbHmGucNA00MKFyxxV6nQU0TaKUiljM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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