SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '26e6addda612c272454366f8d862ca1686a79fff6066e0d71ef6cbd81728df98' 
  AND token = 'EeEzbOEx+Aao8AaJJ9uVyK/l9pWE4m2/e43rI71XB7w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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