SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa5440999a4a09d83cb8e1c83a21d6f79fa86cabd468bf5931f1bab5d5b8f82b' 
  AND token = '5iBJjw3DkWQ82yx0ZUtOePMNhdEH/s905k5UkQqW23k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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