SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f9a2086630fb2c6ea31660bcc2c9f6c66a948761a1fc579cb838ae9957b40636' 
  AND token = 'qTWUNjcyWkuWKCkcjf6LcEsGRuHuep/LEJ/DFB3t24M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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