SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6a33ce80808421216f69988f07cb439256c4f208dc291d8b4cb3366f78d3e212' 
  AND token = 'IAq63ZjFQDO7M9WTuX67iZh0dXN1GGYXYjNVRObu3nY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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