Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c4c5f9e3e2fd644c562f238dc2e5d798f1eb2d13d2b2e81dfa1f9eb56d029853' 
  AND token = 'Mt1Ob/u1I4xHNqlIcxqXn2jue/7CqwRqs4Hu+GBGCPA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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