SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4a14076405312b141102948d074dbfabadcc197b06961a6ef67ea8613b2512e8' 
  AND token = 'eTdL5EwlBkWV96LtQIfS/VNqNOt2f528JuC3xm3uxQA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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