SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '79de548a1d95f6378ce7ab0ad773fd1b4ede032a2315e53b88fc57697f1cdea1' 
  AND token = 'K363vyrB3raIS9UNKRWszIw4HcJE0Dx4Uu2FcC1LMyY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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