SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62cfcbdc4e418f840f3d9600e7d7fbf54e41f2533bad700a6068e35103413c95' 
  AND token = 'n9lRvi5jbK1v17Xi3mimtve+YV6O9lSHjQQReLTr9pk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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