SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97a6021f8b7a9fdbda367f3265f35d80fecad419a884a9b64b440c985b9da433' 
  AND token = 'vphm/hlHHL2w5/deFja8VBiBXcjTcH2K2vFQfC3bAFs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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