SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '46867c27530539e2a5fd5996ea2ecdbe4aacbd49bd86dbbb7e39919c23327648' 
  AND token = '3bHOKWZVoKBcH4eq9vYRu31jJg5PesY41sQIbgyWduo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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