SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '78e65edeb20d7e1513c458b0650683b531a58886a29cbc7162bb0d8875fbc89c' 
  AND token = 'GaGjTDPML9q3jMRfzsjKClVcQCKIZqJj8FvaHGyLQ1A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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