SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '288dc60169f15ff9a1e5d45f4320b8c92b9a5f34f57510406190f3c7997f84dd' 
  AND token = 'gm0mf1h2Z5n0k72r4h5k4fYXRzy0UeZ3EamcW9oV8FE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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