SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2df4ddf2af44bb06895bbfd55e51cffdffd5e1f98eb9fad4ee01ce6962dac4be' 
  AND token = 'QQW0chscvKR7B/PLEAbZdsG5W8ViBdwqthnKZD395/c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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