SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dfedaf3d5cbda780d418dcf81aedbc16126b55c1b09acfb53599afce0fcbb725' 
  AND token = 'eOtuM/AZoZAGSiguoP8HlopxszewPYq+yj/iMpINkYQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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