SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd9b7b1395760e40bd859b3bd678d2d3e6df67dd429f9bac7654413ee8e3ca24a' 
  AND token = 'A+afjkzJv5RK2HvCgDRp0NX/35kb8YFz9TZTXcwY6+4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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