SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62542a5094afcd22ed74786f61e245c77c6163863f92716f8563e46256a9a1a2' 
  AND token = 'QmX2XRzxlXwNhN5IDj6Ufjz6g+DUMwEY/GJgwObrHVI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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