SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd8e7fd568d6fcfaca815da4794b5a9cc0ed69e2fffc3ebbd95189e8c4eab2cb8' 
  AND token = 'l46+BN91V7aZq4swA6BIhIcLygO5hPMvZtilG+DZSyo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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