SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '11e614d3c2bd73b2afbceb95565e114a3fb5b882fd99d39717b93c47477925f8' 
  AND token = 'LoTu3jr4fpYqjgFVLIvSzObGGb9pcZQ+GtpC1AJxyIA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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