SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '128104f2bc49d91572da3628d205fd41686389fa34862d0a29b3ddb67ffee3e8' 
  AND token = 'jPrkyw/d3u6A7t+2ZsqOWdV7SUWvtqwF19+0l8Fv9Lg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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