SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '77fc8d882b29cffd94c4940c04f37ceba6e5a3ee39daff4e3c96496c9c10a725' 
  AND token = 'LapojsbQLFAQDP8tiehlUehSRNC8q2iZZChWJhhJuFM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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