SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '49228494b40741749bbfc2288423246044cd61493d41f4b8094c66a6dee0d9d0' 
  AND token = '/egHTa5kUwhsOvxvm6aQr1ynqgqYs7reY5I91UtkDnE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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