SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '964be8932e1b72f4ef2fc7b7e57d7300a989e9517c804bab1effbcf8618cc9b5' 
  AND token = 'lBELG/iJDxUq/uYtQoCNC4xJEUmHQyEeZ/zBRVGTKIk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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